elements of mechanical engineering - r. k. rajput

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7/21/2019 Elements of Mechanical Engineering - R. K. Rajput http://slidepdf.com/reader/full/elements-of-mechanical-engineering-r-k-rajput 1/137 Scilab Textbook Companion for Elements of Mechanical Engineering by R. K. Rajput 1 Created by Vatsal Shah B.TECH Mechanical Engineering Institute of Technology,Nirma University College Teacher None Cross-Checked by Bhavani Jalkrish September 25, 2014 1 Funded by a grant from the National Mission on Education through ICT, http://spoken-tutorial.org/NMEICT-Intro. This Textbook Companion and Scilab codes written in it can be downloaded from the ”Textbook Companion Project” section at the website http://scilab.in

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Page 1: Elements of Mechanical Engineering - R. K. Rajput

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Scilab Textbook Companion for

Elements of Mechanical Engineering

by R. K. Rajput1

Created byVatsal Shah

B.TECHMechanical Engineering

Institute of Technology,Nirma UniversityCollege Teacher

NoneCross-Checked byBhavani Jalkrish

September 25, 2014

1Funded by a grant from the National Mission on Education through ICT,http://spoken-tutorial.org/NMEICT-Intro. This Textbook Companion and Scilabcodes written in it can be downloaded from the ”Textbook Companion Project”section at the website http://scilab.in

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Book Description

Title:  Elements of Mechanical Engineering

Author:   R. K. Rajput

Publisher:   Laxmi Publications, New Delhi.

Edition:   1

Year:   2009

ISBN:   978-81-318-0677-7

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Scilab numbering policy used in this document and the relation to theabove book.

Exa  Example (Solved example)

Eqn  Equation (Particular equation of the above book)

AP  Appendix to Example(Scilab Code that is an Appednix to a particularExample of the above book)

For example, Exa 3.51 means solved example 3.51 of this book. Sec 2.3 meansa scilab code whose theory is explained in Section 2.3 of the book.

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Contents

List of Scilab Codes   4

2 Fuels and Combustion   8

3 Properties of Gases   11

4 Properties of Steam   23

5 Heat Engines   51

6 Steam Boilers   80

7 Internal Combustion Engines   96

10 Air Compressors   115

13 Transmission of Motion and Power   123

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List of Scilab Codes

Exa 2.1 Example 1   . . . . . . . . . . . . . . . . . . . . . . . . 8Exa 2.2 Example 2   . . . . . . . . . . . . . . . . . . . . . . . . 9Exa 3.1 Example 1   . . . . . . . . . . . . . . . . . . . . . . . . 11Exa 3.2 Example 2   . . . . . . . . . . . . . . . . . . . . . . . . 11Exa 3.3 Example 3   . . . . . . . . . . . . . . . . . . . . . . . . 12Exa 3.4 Example 4   . . . . . . . . . . . . . . . . . . . . . . . . 13Exa 3.5 Example 5   . . . . . . . . . . . . . . . . . . . . . . . . 14Exa 3.6 Example 6   . . . . . . . . . . . . . . . . . . . . . . . . 14Exa 3.8 Example 8   . . . . . . . . . . . . . . . . . . . . . . . . 15Exa 3.10 Example 10  . . . . . . . . . . . . . . . . . . . . . . . . 17Exa 3.11 Example 11  . . . . . . . . . . . . . . . . . . . . . . . . 18Exa 3.12 Example 12  . . . . . . . . . . . . . . . . . . . . . . . . 20Exa 3.13 Example 13  . . . . . . . . . . . . . . . . . . . . . . . . 21

Exa 4.1 Example 1   . . . . . . . . . . . . . . . . . . . . . . . . 23Exa 4.2 Example 2   . . . . . . . . . . . . . . . . . . . . . . . . 23Exa 4.3 Example 3   . . . . . . . . . . . . . . . . . . . . . . . . 24Exa 4.4 Example 4   . . . . . . . . . . . . . . . . . . . . . . . . 26Exa 4.5 Example 5   . . . . . . . . . . . . . . . . . . . . . . . . 27Exa 4.6 Example 6   . . . . . . . . . . . . . . . . . . . . . . . . 28Exa 4.7 Example 7   . . . . . . . . . . . . . . . . . . . . . . . . 29Exa 4.8 Example 8   . . . . . . . . . . . . . . . . . . . . . . . . 30Exa 4.9 Example 9   . . . . . . . . . . . . . . . . . . . . . . . . 30Exa 4.10 Example 10  . . . . . . . . . . . . . . . . . . . . . . . . 32Exa 4.11 Example 11  . . . . . . . . . . . . . . . . . . . . . . . . 34

Exa 4.12 Example 12  . . . . . . . . . . . . . . . . . . . . . . . . 35Exa 4.13 Example 13  . . . . . . . . . . . . . . . . . . . . . . . . 36Exa 4.14 Example 14  . . . . . . . . . . . . . . . . . . . . . . . . 37Exa 4.15 Example 15  . . . . . . . . . . . . . . . . . . . . . . . . 38

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Exa 4.16 Example 16  . . . . . . . . . . . . . . . . . . . . . . . . 38

Exa 4.17 Example 17  . . . . . . . . . . . . . . . . . . . . . . . . 39Exa 4.18 Example 18  . . . . . . . . . . . . . . . . . . . . . . . . 40Exa 4.19 Example 19  . . . . . . . . . . . . . . . . . . . . . . . . 41Exa 4.20 Example 20  . . . . . . . . . . . . . . . . . . . . . . . . 42Exa 4.21 Example 21  . . . . . . . . . . . . . . . . . . . . . . . . 43Exa 4.22 Example 22  . . . . . . . . . . . . . . . . . . . . . . . . 44Exa 4.23 Example 23  . . . . . . . . . . . . . . . . . . . . . . . . 45Exa 4.24 Example 24  . . . . . . . . . . . . . . . . . . . . . . . . 46Exa 4.25 Example 25  . . . . . . . . . . . . . . . . . . . . . . . . 47Exa 4.26 Example 26  . . . . . . . . . . . . . . . . . . . . . . . . 48Exa 4.27 Example 27  . . . . . . . . . . . . . . . . . . . . . . . . 49

Exa 5.1 Example 1   . . . . . . . . . . . . . . . . . . . . . . . . 51Exa 5.2 Example 2   . . . . . . . . . . . . . . . . . . . . . . . . 53Exa 5.3 Example 3   . . . . . . . . . . . . . . . . . . . . . . . . 54Exa 5.4 Example 4   . . . . . . . . . . . . . . . . . . . . . . . . 55Exa 5.5 Example 5   . . . . . . . . . . . . . . . . . . . . . . . . 57Exa 5.6 Example 6   . . . . . . . . . . . . . . . . . . . . . . . . 58Exa 5.7 Example 7   . . . . . . . . . . . . . . . . . . . . . . . . 60Exa 5.8 Example 8   . . . . . . . . . . . . . . . . . . . . . . . . 61Exa 5.9 Example 9   . . . . . . . . . . . . . . . . . . . . . . . . 62Exa 5.10 Example 10  . . . . . . . . . . . . . . . . . . . . . . . . 63

Exa 5.11 Example 11  . . . . . . . . . . . . . . . . . . . . . . . . 65Exa 5.12 Example 12  . . . . . . . . . . . . . . . . . . . . . . . . 66Exa 5.13 Example 13  . . . . . . . . . . . . . . . . . . . . . . . . 67Exa 5.14 Example 14  . . . . . . . . . . . . . . . . . . . . . . . . 68Exa 5.15 Example 15  . . . . . . . . . . . . . . . . . . . . . . . . 69Exa 5.16 Example 16  . . . . . . . . . . . . . . . . . . . . . . . . 70Exa 5.17 Example 17  . . . . . . . . . . . . . . . . . . . . . . . . 73Exa 5.18 Example 18  . . . . . . . . . . . . . . . . . . . . . . . . 74Exa 5.19 Example 19  . . . . . . . . . . . . . . . . . . . . . . . . 75Exa 5.20 Example 20  . . . . . . . . . . . . . . . . . . . . . . . . 76Exa 5.21 Example 21  . . . . . . . . . . . . . . . . . . . . . . . . 76

Exa 6.1 Example 1   . . . . . . . . . . . . . . . . . . . . . . . . 80Exa 6.2 Example 2   . . . . . . . . . . . . . . . . . . . . . . . . 81Exa 6.3 Example 3   . . . . . . . . . . . . . . . . . . . . . . . . 82Exa 6.4 Example 4   . . . . . . . . . . . . . . . . . . . . . . . . 83Exa 6.5 Example 5   . . . . . . . . . . . . . . . . . . . . . . . . 84

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Exa 6.6 Example 6   . . . . . . . . . . . . . . . . . . . . . . . . 85

Exa 6.7 Example 7   . . . . . . . . . . . . . . . . . . . . . . . . 86Exa 6.8 Example 8   . . . . . . . . . . . . . . . . . . . . . . . . 88Exa 6.9 Example 9   . . . . . . . . . . . . . . . . . . . . . . . . 89Exa 6.10 Example 10  . . . . . . . . . . . . . . . . . . . . . . . . 90Exa 6.11 Example 11  . . . . . . . . . . . . . . . . . . . . . . . . 91Exa 6.12 Example 12  . . . . . . . . . . . . . . . . . . . . . . . . 92Exa 6.13 Example 13  . . . . . . . . . . . . . . . . . . . . . . . . 94Exa 6.14 Example 14  . . . . . . . . . . . . . . . . . . . . . . . . 95Exa 7.1 Example 1   . . . . . . . . . . . . . . . . . . . . . . . . 96Exa 7.2 Example 2   . . . . . . . . . . . . . . . . . . . . . . . . 97Exa 7.3 Example 3   . . . . . . . . . . . . . . . . . . . . . . . . 97

Exa 7.4 Example 4   . . . . . . . . . . . . . . . . . . . . . . . . 98Exa 7.5 Example 5   . . . . . . . . . . . . . . . . . . . . . . . . 98Exa 7.6 Example 6   . . . . . . . . . . . . . . . . . . . . . . . . 99Exa 7.7 Example 7   . . . . . . . . . . . . . . . . . . . . . . . . 101Exa 7.8 Example 8   . . . . . . . . . . . . . . . . . . . . . . . . 102Exa 7.9 Example 9   . . . . . . . . . . . . . . . . . . . . . . . . 103Exa 7.10 Example 10  . . . . . . . . . . . . . . . . . . . . . . . . 104Exa 7.11 Example 11  . . . . . . . . . . . . . . . . . . . . . . . . 105Exa 7.12 Example 12  . . . . . . . . . . . . . . . . . . . . . . . . 107Exa 7.13 Example 13  . . . . . . . . . . . . . . . . . . . . . . . . 108

Exa 7.14 Example 14  . . . . . . . . . . . . . . . . . . . . . . . . 109Exa 7.15 Example 15  . . . . . . . . . . . . . . . . . . . . . . . . 110Exa 7.16 Example 16  . . . . . . . . . . . . . . . . . . . . . . . . 111Exa 7.17 Example 17  . . . . . . . . . . . . . . . . . . . . . . . . 113Exa 10.1 Example 1   . . . . . . . . . . . . . . . . . . . . . . . . 115Exa 10.2 Example 2   . . . . . . . . . . . . . . . . . . . . . . . . 116Exa 10.3 Example 3   . . . . . . . . . . . . . . . . . . . . . . . . 117Exa 10.4 Example 4   . . . . . . . . . . . . . . . . . . . . . . . . 118Exa 10.5 Example 5   . . . . . . . . . . . . . . . . . . . . . . . . 119Exa 10.6 Example 6   . . . . . . . . . . . . . . . . . . . . . . . . 121Exa 13.1 Example 1   . . . . . . . . . . . . . . . . . . . . . . . . 123

Exa 13.2 Example 2   . . . . . . . . . . . . . . . . . . . . . . . . 124Exa 13.3 Example 3   . . . . . . . . . . . . . . . . . . . . . . . . 124Exa 13.4 Example 4   . . . . . . . . . . . . . . . . . . . . . . . . 125Exa 13.5 Example 5   . . . . . . . . . . . . . . . . . . . . . . . . 126Exa 13.6 Example 6   . . . . . . . . . . . . . . . . . . . . . . . . 127

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Exa 13.7 Example 7   . . . . . . . . . . . . . . . . . . . . . . . . 128

Exa 13.8 Example 8   . . . . . . . . . . . . . . . . . . . . . . . . 130Exa 13.9 Example 9   . . . . . . . . . . . . . . . . . . . . . . . . 131Exa 13.10 Example 10  . . . . . . . . . . . . . . . . . . . . . . . . 132Exa 13.11 Example 11  . . . . . . . . . . . . . . . . . . . . . . . . 133Exa 13.12 Example 12  . . . . . . . . . . . . . . . . . . . . . . . . 134Exa 13.13 Example 13  . . . . . . . . . . . . . . . . . . . . . . . . 135

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Chapter 2

Fuels and Combustion

Scilab code Exa 2.1  Example 1

1   clc

2   clear

3   //DATA GIVEN4   c = 8 8 ;   //% o f c ar bo n i n c o a l5   h = 4 . 2 ;   //% o f h yd ro ge n i n c o a l6   W f = 0 . 8 4 8 ;   // w e ig ht o f c o al i n g

7   W f w = 0 . 0 2 7 ;   // w ei gh t o f f u s e w ir e i nc a l o r i m e t e r i n g

8   W = 1 9 5 0 ;   // w e ig h t o f w at er i nc a l o r i m e t e r i n g

9   W e = 3 8 0 ;   // w at er e q u i v al e n t o f  c a l o r i m e t e r

10   D t = 3 . 0 6 ;   // o b s er v e d t e mp e r at u r e r i s e( t2−t 1 ) i n deg c e l s i u s

11   t c = 0 . 0 1 7 ;   // c o o l i n g c o r r e c t i o n i n degc e l s i u s

12   c f w = 6 7 0 0 ;   / / c a l o r i f i c v a l u e o f f u s ew ir e i n J / g13

14   //CALCULATIONS15   c t r = ( D t ) + t c ;   // c o r r e c t e d temp . r i s e

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16   H w = ( W + W e ) * 4 . 1 8 * [ c t r ] ;   // h ea t r e c i e v e d by w a te r i n

J17   H f w = W f w * c f w ;   // h ea t g i ve n o ut by f u s ew i re i n J

18   H c f = H w - H f w ;   / / h e a t p r od u ce d d ue t oc o m b us t i o n o f f u e l i n J

19   H C V = H c f / W f ;   / / h i g h e r c a l o r i f i c v a l u e o f  f u e l i n kJ /kg

20   M s = 9 * h / 1 0 0 ;   // s te am p ro du ce d p e r kg o f  c o a l

21   LCV=HCV -2465* Ms;   / / l o w e r c a l o r i f i c v a l u e o f  f u e l i n kJ /kg

2223   printf ( ’ The H i g he r c a l o r i f i c v a l u e o f f u e l , H . C .V .

i s : %5 . 1 f kJ / k g .   \n ’ , H C V ) ;

24   printf ( ’ The L ower c a l o r i f i c v a l u e o f f u e l , L . C . V .i s : %5 . 1 f kJ / k g .   \n ’ , L C V ) ;

Scilab code Exa 2.2  Example 2

1   clc2   clear

3   //DATA GIVEN4   V 1 = 0 . 0 8 ;   // g a s b ur nt i n c a l o r i m e t e r

i n m ˆ 35   P g = 5 . 2 ;   // p r e s s ur e o f g as s up pl y i n

cm o f w at er6   P b = 7 5 . 5 ;   / / b a ro m et er r e a d i n g i n cm

o f Hg7   W w = 2 8 ;   / / w e ig h t o f w at er h e at e d by

g as i n kg8   T g = 1 3 ;   // t em p er at u re o f g as i n degc e l s i u s

9   T w i = 1 0 ;   / / t e mp e r at u r e o f w at er a ti n l e t i n deg c e l s i u s

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10   T w o = 2 3 . 5 ;   / / t e mp e r at u r e o f w at er a t

o u t l e t i n deg c e l s i u s11   M s = 0 . 0 6 ;   / / st ea m c o nd e ns e d i n kg12

13   //CALCULATIONS14   / / by u s i ng g e n e r a l g as e qu at io n , r e d uc i n g t he volume

t o S . T . P .15   //p1∗V1/T1=p2∗V2/T216   p 1 = P b + ( P g / 1 3 . 6 ) ;   / / i n cm o f Hg17   T 1 = T g + 2 7 3 ;   / / i n K18   p 2 = 7 6 ;   / / i n cm o f Hg19   T 2 = 1 5 + 2 7 3 ;   / / i n K

20   V 2 = p 1 * V 1 * T 2 / T 1 / p 2 ;   // in mˆ321   H w = W w * 4 . 1 8 * ( T w o - T w i ) ;   // h ea t r e c i e v e d by w at er i n

kJ22   H C V = H w / V 1 ;   / / h i g h e r c a l o r i f i c v a l u e o f  

f u e l i n kJ /mˆ 323   LCV=HCV -2465* Ms/V1;   / / l o w e r c a l o r i f i c v a l u e o f  

f u e l i n kJ /mˆ324

25   printf ( ’ The C a l o r i f i c v al u e s o f f u e l p e r mˆ3 o f g a sa t 15 deg c e l s i u s and 76 cm o f Hg p r e s s u r e a re :

\n ’) ;

26   printf ( ’ The H i gh er c a l o r i f i c v a l u e o f f u e l , H . C. V.i s : %5 . 1 f k J /mˆ 3 .   \n ’ , H C V ) ;

27   printf ( ’ The L ow er c a l o r i f i c v a l u e o f f u e l , L . C . V .i s : %5 . 1 f kJ /mˆ 3 .   \n ’ , L C V ) ;

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Chapter 3

Properties of Gases

Scilab code Exa 3.1  Example 1

1   clc

2   clear

3   //DATA GIVEN4   Q = - 5 0 ;   // h ea t r e j e c t e d t o

c o o l i n g w a te r i n kJ /kg5   W = - 1 0 0 ;   // w ork i n p u t i n kJ /

kg6

7   / / u s i n g F i r s t Law o f T he rm od yn am ic s , Q=( u2−u1 )+W8   D u = Q - W ;   / / ( u 2−u1 ) c ha ng e i n

i n t e r n a l e ne rg y i n kJ /kg9   // s i n c e Du i s +ve , t h er e i s g ai n i n i n t e r n a l e ne rg y

10

11   printf ( ’ The GAIN i n i n t e r n a l e n er g y i s : %2 . 0 f kJ / kg .\n ’ , D u ) ;

Scilab code Exa 3.2  Example 2

11

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1   clc

2   clear3   //DATA GIVEN4   u 1 = 4 5 0 ;   // i n t e r n a l e ne rg y a t

b e gi n ni n g o f t he e xp an si on i n kJ /kg5   u 2 = 2 2 0 ;   // i n t e r n a l e ne rg y

a f t e r e xp an si on i n kJ /kg6   W = 1 2 0 ;   / / wor k d on e by t h e

a i r d ur in g e xp an si on i n kJ /kg7

8   / / u s i n g F i r s t Law o f T he rm od yn am ic s , Q=( u2−u1 )+W9   Q = ( u 2 - u 1 ) + W ;   // h e at f l o w i n kJ / kg

10   // s i n c e Q i s   −ve , t he r e i s r e j e c t i o n o f h e a t11

12   printf ( ’ T he h e a t REJECTED b y a i r i s : %3 . 0 f k J / k g .   \n’ , ( - Q ) ) ;

Scilab code Exa 3.3  Example 3

1   clc

2   clear3   //DATA GIVEN4   m = 0 . 3 ;   // mass o f n i t r o g e n

i n kg5   p 1 = 0 . 1 ;   / / p r e s s u r e i n MPa6   T 1 = 4 0 + 2 7 3 ;   / / t e m p e ra t u r e b e f o r e

c o mp r es s io n i n K7   p 2 = 1 ;   / / p r e s s u r e i n MPa8   T 2 = 1 6 0 + 2 7 3 ;   // t e mp e ra t u re a f t e r

c o mp r es s io n i n K

9   W = - 3 0 ;   / / wor k d on e d u r i n gt he c o mp r es s io n i n kJ / kg10   C v = 0 . 7 5   // i n k J /kgK11

12   / / u s i n g F i r s t Law o f T he rm od yn am ic s , Q=( u2−u1 )+W

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13   / / ( u 2−u1 )=m∗Cv∗ ( T2−T1 )

14   D u = m * C v * ( T 2 - T 1 ) ;15   Q = D u + W ;   // h e at f l o w i n kJ / kg16   // s i n c e Q i s   −ve , t he r e i s r e j e c t i o n o f h e a t17

18   printf ( ’ T he h e a t REJECTED b y a i r i s : %1 . 0 f k J .   \n ’, ( - Q ) ) ;

Scilab code Exa 3.4  Example 4

1   clc

2   clear

3   //DATA GIVEN4   // i n i t i a l s t a t e5   p 1 = 0 . 1 0 5 ;   // p r e s s ur e o f g as i n

MPa6   V 1 = 0 . 4 ;   // v olume o f g as i n m

ˆ37   // f i n a l s t a t e8   p 2 = 0 . 1 0 5 ;   // p r e s s ur e o f g as i n

MPa9   V 2 = 0 . 2 0 ;   // v olume o f g as i n m

ˆ310

11   Q = - 4 2 . 5 ;   // h ea t t r a n s f e r r e di n kJ

12   p = p 1 ;

13

14   / / p r o c e s s u se d−   ISOBARIC ( C onst an t pr e s su r e )15   W 1 2 = p * ( V 2 - V 1 ) * 1 0 0 0 ;   // w ork i n kJ

16   / / u s i n g F i r s t Law o f T he rm od yn am ic s , Q=( u2−u1 )+W17   D u = Q - W 1 2 ;   / / ( u 2−u1 ) c ha ng e i ni n t e r n a l e ne rg y i n kJ

18   / / s i n c e Du i s   −ve , t h e re i s d e c r e a s e i n i n t e r n a le n e r g y

13

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19

20   printf ( ’ The DECREASE i n i n t e r n a l e n e r g y i s : %2 . 1 f k J.   \n ’  , ( - D u ) ) ;

Scilab code Exa 3.5  Example 5

1   clc

2   clear

3   //DATA GIVEN

4   / / p a r t −15   // pr e s su r e =p1 , t e m pe r at u r e =T16   / / p a r t −27   // pr e s su r e =p2 , t e m pe r at u r e =T28

9   / / A cc . F i r s t Law o f T he rm o dy na mi cs , Q=( u2−u1 )+W10   / / when p a r t i t i o n moved11   D Q = 0 ;

12   D W = 0 ;

13   D U = D Q - D W ;

14   //DU=0

1516   printf ( ’ CONCLUSION :   \n ’ ) ;

17   printf ( ’ Acc . t o F i r s t Law o f T hermodynamics ,   \n ’ ) ;

18   printf ( ’ When p ar t i o n moved , t h er e i sc o n s er v a t i o n o f i n t e r n a l e ne rg y .   \n ’ ) ;

Scilab code Exa 3.6  Example 6

1   clc

2   clear

3   //DATA GIVEN4   // i n i t i a l s t a t e

14

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5   p 1 = 1 0 ^ 5 ;   // i n i t i a l pr e s su r e

o f a i r i n Pa6   v 1 = 1 . 8 ;   // v olume o f a i r i n mˆ 3 / k g

7   T 1 = 2 5 + 2 7 3 ;   // i n i t i a lt em pe r at ur e o f a i r i n K

8   // f i n a l s t a t e9   p 2 = 5 * 1 0 ^ 5 ;   // f i n a l p r e s s u re o f  

a i r i n Pa10   T 2 = 2 5 + 2 7 3 ;   // f i n a l t e mp e r at u re

o f a i r i n K11

12   / / p r o c e s s u se d−   ISOTHERMAL ( Co ns ta nt te mp er at u re )13   W 1 2 = [ p 1 * v 1 * log ( p 1 / p 2 ) ] / 1 0 0 0 ;   / / wor k i n kJ / kg14   / / s i n c e W i s   −ve , work i s s u pp l ie d t o t h e a i r15

16   / / s i n c e t em p er a tu re i s c o n st a n t17   D u = 0 ;   / / ( u 2−u1 ) c ha ng e i n

i n t e r n a l e ne rg y i n kJ /kg18

19   / / u s i n g F i r s t Law o f T he rm od yn am ic s , Q=( u2−u1 )+W20   Q = D u + W 1 2 ;

21  // s i n c e Q i s   −ve , t he r e i s r e j e c t i o n o f h e a t froms ys te m t o s u r r ou n d i ng s

22

23   printf ( ’ ( i ) The Work d on e on t h e a i r i s : %3 . 1 f kJ /kg .   \n ’  , ( - W 1 2 ) ) ;

24   printf ( ’ ( i i ) The c ha ng e i n i n t e r n a l e ne rg y i s : %1 . 0f k J / kg .   \n ’  , ( D u ) ) ;

25   printf ( ’ ( i i i ) The Heat REJECTED i s : %3. 1 f kJ/ kg .   \n ’, ( - Q ) ) ;

Scilab code Exa 3.8  Example 8

1   clc

15

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2   clear

3   //DATA GIVEN4   p 1 = 4 * 1 0 ^ 5 ;   // i n i t i a l pr e s su r ei n N/mˆ2

5   V 1 = 0 . 2 ;   // i n i t i a l volume inmˆ3

6   T 1 = 1 3 0 + 2 7 3 ;   // i n i t i a lt e mp e r at u r e i n K

7   p 2 = 1 . 0 2 * 1 0 ^ 5 ;   // f i n a l p r e s su r ea f t e r a d i a b a t i c e xp a ns i on i n N/mˆ2

8   Q 2 3 = 7 2 . 5 ;   // i n c r e a s e i ne nt ha l p y d ur in g c o ns t a n t p r e s su r e p r o c es s i n kJ

9   C p = 1 ;   // i n k J /kgK10   C v = 0 . 7 1 4 ;   // in kJ/khK11

12   / /gamma f o r a i r , g13   g = C p / C v ;

14   R = ( C p - C v ) * 1 0 0 0 ;

15

16   // f o r r e v e r s i b l e a d i a b a t i c p r o c e s s 1−217   //p1 ∗ (V1ˆg)=p2∗ ( V 2ˆg)18   V 2 = V 1 * ( p 1 / p 2 ) ^ ( 1 / g ) ;   // f i n a l volume i n m

ˆ319   // ( T2/T1) =( p2/p1) ˆ( ( g−1) /g ) ;20   T 2 = T 1 * ( p 2 / p 1 ) ^ ( ( g - 1 ) / g ) ; ;   // f i n a l temp . T2 i n

K21

22   m = p 1 * V 1 / R / T 1 ;   // m ass i n kg23

24   / / f o r c o ns t an t p r e s su r e p r o c es s 2−325   //Q23=m∗Cp∗( T3−T2) ;26   T 3 = Q 2 3 / m / C p + T 2 ;

27   //V2/T2=V3/T3

28   V 3 = V 2 / T 2 * T 3 ;29

30   / /Work d on e by t h e p at h 1−2−3, W123=W12+W2331   W 1 2 = ( p 1 * V 1 - p 2 * V 2 ) / ( g - 1 ) ;

32   W 2 3 = p 2 * ( V 3 - V 2 ) ;

16

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33   W 1 2 3 = W 1 2 + W 2 3 ;

3435   // i f t he abov e p r o c e s s e s a re r e p l a c e d by a s i n g l e

r e v e r s i b l e p o l y t r o p i c p r oc e ss g i v i n g t h e samewo rk b et we en i n i t i a l and f i n a l s t a t e s ,

36   //W13=W123=(p1V1−p3V3) /( n−1)37   p 3 = p 2 ;

38   n = 1 + ( p 1 * V 1 - p 3 * V 3 ) / W 1 2 3 ;   / / i n d e x o f e x p an s i o n, n

39

40   printf ( ’ ( i ) The T o t a l Work d on e i s : %5 . 0 f Nm o r J .\n ’ , W 1 2 3 ) ;

41   printf ( ’ ( i i ) The v al ue o f i nd ex o f e xp an si on , n i s :%1. 3 f .   \n ’ , n ) ;

42

43   //NOTE:44   / / t h e r e i s s l i g h t v a r i a t i o n i n a ns we r s o f t he book

due t o r ou nd in g o f f o f t he v a lu e s

Scilab code Exa 3.10  Example 10

1   clc

2   clear

3   //DATA GIVEN4   // i n i t i a l s t a t e5   p 1 = 1 0 ^ 5 ;   // i n i t i a l pr e s su r e

o f g a s i n Pa6   V 1 = 0 . 4 5 ;   // i n i t i a l volume o f  

g a s i n mˆ 37   T 1 = 8 0 + 2 7 3 ;   // i n i t i a l

t em pe ra tu re o f g as i n K8   // f i n a l s t a t e9   p 2 = 5 * 1 0 ^ 5 ;   // f i n a l p r e s s u re o f  

g as i n Pa10   V 2 = 0 . 1 3 ;   // f i n a l volume o f  

17

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g a s i n mˆ 3

1112   / /gamma f o r a i r , g13   g = 1 . 4 ;

14   R = 2 9 4 . 2   //J/kgK15

16   m = p 1 * V 1 / R / T 1 ;   // m ass i n kg17

18   //p1 ∗ (V1ˆn)=p2 ∗ (V2ˆn)19   n = log ( p 1 / p 2 ) / log ( V 2 / V 1 ) ;   / / i n d e x n20

21   / / I n a p o l y t r o p i c p r oc e ss

22   // (T2/T1) =(V1/V2) ˆ( n−1) ;23   T 2 = T 1 * ( V 1 / V 2 ) ^ ( n - 1 ) ;   / / temp . T2 i n K24

25   C v = R / ( g - 1 ) ;

26   D u = m * C v * ( T 2 - T 1 ) / 1 0 0 0 ;   // i n c r e a s e i ni n t e r n a l e ne rg y i n kJ

27

28   / / u s i n g F i r s t Law o f T he rm od yn am ic s , Q=( u2−u1 )+W29   //W12=(p1∗V1−p2 ∗V2) /( n−1)=mR( T2−T1) /( n−1)30   W 1 2 = m * R * ( T 1 - T 2 ) / ( n - 1 ) / 1 0 0 0 ;

31   Q = D u + W 1 2 ;

32   // s i n c e Q i s   −ve , t he r e i s r e j e c t i o n o f h e a t froms ys te m t o s u r r ou n d i ng s

33

34   printf ( ’ ( i ) The Mass o f t he g as i s : %1 . 3 f kg .   \n ’  ,(

 m ) ) ;

35   printf ( ’ ( i i ) The i n d ex n i s : %1 . 3 f .   \n ’  ,(n)) ;

36   printf ( ’ ( i i i ) The c ha ng e i n i n t e r n a l e n er g y i s : %2 . 1f kJ .   \n ’ , ( D u ) ) ;

37   printf ( ’ ( iv ) The Heat REJECTED i s : %2. 2 f kJ .   \n ’  ,( -

Q ) ) ;

Scilab code Exa 3.11  Example 11

18

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1   clc

2   clear3   //DATA GIVEN4   // i n i t i a l s t a t e5   p 1 = 1 . 0 2 ;   // i n i t i a l pr e s su r e

o f a i r i n ba r6   V 1 = 0 . 0 1 5 ;   // i n i t i a l volume o f  

a i r i n mˆ37   T 1 = 2 2 + 2 7 3 ;   // i n i t i a l

t em pe r at ur e o f a i r i n K8   // f i n a l s t a t e9   p 2 = 6 . 8 ;   // f i n a l p r e s s u re o f  

a i r i n ba r10   / / Law o f a d i a b a t i c c o m p r e s s i o n , pVˆ g=C11

12   / /gamma f o r a i r , g13   g = 1 . 4

14   R = 0 . 2 8 7 ;

15

16   / / I n a a d i a b a t i c p r o c e s s17   // ( T2/T1) =( p2/p1) ˆ( ( g−1) /g ) ;18   T 2 = T 1 * ( p 2 / p 1 ) ^ ( ( g - 1 ) / g ) ; ;   // f i n a l temp . T2 i n

K19

20   //p1 ∗ (V1ˆg)=p2∗ ( V 2ˆg)21   V 2 = V 1 * ( p 1 / p 2 ) ^ ( 1 / g ) ;   // f i n a l volume i n m

ˆ322

23   m = p 1 * 1 0 ^ 5 * V 1 / 1 0 ^ 3 / R / T 1 ;   // m ass i n kg24

25   //W=(p1∗V1−p2∗V2) /( g−1)=mR( T2−T1) /( g−1)26   W = m * R * ( T 1 - T 2 ) / ( g - 1 ) ;

27   / / s i n c e W i s   −ve , t he work i s done on t he a i r

2829   printf ( ’ ( i ) The F i n a l t e m pe r a tu r e i s : %3 . 2 f d eg .

c e l s i u s .   \n ’  , ( T2 - 2 7 3 ) ) ;

30   printf ( ’ ( i i ) The F i n a l Volume i s : %1 . 5 f mˆ 3 .   \n ’ , V2

) ;

19

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31   printf ( ’ ( i i i ) The Work d on e on t h e a i r i s : %1 . 3 f kJ .

\n ’ , ( - W ) ) ;

Scilab code Exa 3.12  Example 12

1   clc

2   clear

3   //DATA GIVEN4   m = 0 . 4 4 ;   // mass o f a i r i n kg

5   T 1 = 1 8 0 + 2 7 3 ;   // i n i t i a lt em pe r at ur e o f a i r i n K6   T 2 = 1 5 + 2 7 3 ;   // f i n a l t e mp e r at u re

o f a i r i n K7   W 1 2 = 5 2 . 5 ;   / / wor k d on e d u r i n g

t h e p r oc e ss i n kJ8   //V2/V1=39   V r = 3 ;   / / v ol um e r a t i o , Vr=

V2/V110

11   / / Law o f a d i a b a t i c e x p a n s i o n , pVˆ g=C

1213   // I n an a d i a b a t i c p r o c e s s14   // (T2/T1) =(V1/V2) ˆ( g−1) ;15   g = 1 + [ ( log ( T 2 / T 1 ) / log ( 1 / V r ) ) ] ;   //gamma

f o r a i r , g=Cp /Cv16

17   //W12=(p1∗V1−p2 ∗V2) /( n−1)=mR( T2−T1) /( g−1)18   R = W 1 2 / m / ( T 1 - T 2 ) * ( g - 1 ) ;

19   //R=Cp−Cv20

21   C v = R / ( g - 1 ) ;22   C p = g * C v ;

23

24   printf ( ’ ( i ) The v a l u e o f Cv i s : %1 . 3 f kJ /kgK .   \n ’ ,

C v ) ;

20

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25   printf ( ’ ( i i ) The v a l u e o f Cp i s : %1 . 3 f kJ /kgK .   \n ’ ,

C p ) ;26

27   //NOTE:28   / / t h e r e i s s l i g h t v a r i a t i o n i n a ns we r s o f t he book

due t o r ou nd in g o f f o f t he v a lu e s

Scilab code Exa 3.13  Example 13

1   clc2   clear

3   //DATA GIVEN4   m = 1 ;   // mass o f e ta hn e g as

i n kg5   M = 3 0 ;   / / m o l e c u l a r w e i g ht

o f e th a ne6   p 1 = 1 . 1 ;   // i n i t i a l pr e s su r e

i n b ar7   T 1 = 2 7 + 2 7 3 ;   // i n i t i a l

t e mp e r at u r e i n K

8   p 2 = 6 . 6 ;   // f i n a l p r e s s u re i nb ar

9   C p = 1 . 7 5 ;   // i n k J /kgK10

11   / / Law o f c o m p r e s s i o n , pV ˆ 1. 3 =C12   n = 1 . 3 ;

13

14   // C h a r a c t e r i s t i c g as c on st an t , R = U n i ve r sa l g asc o n s t a n t ( Ro ) / M o l e c u l a r w e i g ht (M)

15   R o = 8 3 1 4 ;

16   R = R o / M / 1 0 0 0 ;   //kJ/kgK17

18   //R=Cp−Cv19   C v = C p - R ;

20   g = C p / C v ;   //gamma g

21

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21

22   / / I n a p o l y t r o p i c p r oc e ss23   // ( T2/T1) =( p2/p1) ˆ( ( n−1)/n) ;24   T 2 = T 1 * ( p 2 / p 1 ) ^ ( ( n - 1 ) / n ) ; ;   // f i n a l temp . T2 i n

K25

26   //W=(p1∗V1−p2∗V2) /( n−1)=mR( T2−T1) /( g−1)27   W = m * R * ( T 1 - T 2 ) / ( n - 1 ) ;

28

29   Q = [ ( g - n ) / ( g - 1 ) ] * W ;   // h e at f l o w i n kJ / kg30

31   printf ( ’ The H e at SUPPLIED i s : %2. 1 f k J /k g .   \n ’  ,(Q))

;

22

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Chapter 4

Properties of Steam

Scilab code Exa 4.1  Example 1

1   clc

2   clear

3   //DATA GIVEN4   M s = 5 0 ;   / / mass o f d ry s te am

i n kg5   M w = 1 . 5 ;   // mass o f w at er i n

s u s pe n si o n i n kg6

7   / / d r y n e s s f r a c t i o n , x =( ma ss o f d ry s te am ) / ( m as s o f  d ry s te am +mass o f w at er i n s u s p e n s i o n )

8   x = M s / ( M s + M w ) ;

9

10   printf ( ’ The D ry ne ss f r a c t i o n ( Q u al i ty ) o f stea m i s :%1. 3 f . ’ , x ) ;

Scilab code Exa 4.2  Example 2

1   clc

23

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2   clear

3   //DATA GIVEN4   V = 0 . 6 ;   / / vo lu me o f t h ev e s s e l i n mˆ3

5   p = 0 . 5 ;   // p r e s s u r e i n b ar6   M = 3 ;   // mass o f l i q u i d and

w at er v ap ou r i n kg7

8   v = V / M ;   // s p e c i f i c volume inmˆ3/kg

9   / / At 5 b ar , f ro m s te am t a b l e s10   v g = 0 . 3 7 5 ;   //mˆ3/kg

11   v f = 0 . 0 0 1 0 9 ;   //mˆ3/kg12   v f g = v g - v f ;

13   //v=vg−(1−x ) v f g14   x = ( v - v g ) / v f g + 1 ;   // q u a l i t y o f t he

v apour15

16   / / mass and volume o f l i q u i d17   M l i q = M * ( 1 - x ) ;

18   V l i q = M l i q * v f ;

19

20  / / m as s a nd v ol um e o f v ap o ur21   M v a p = M * x ;

22   V v a p = M v a p * v g ;

23

24   printf ( ’ ( i ) The Mass and Volume o f l i q u i d i s :   \n ’ ) ;

25   printf ( ’ Ml i q . i s : %1 . 3 f kg .   \n ’ , M l i q ) ;

26   printf ( ’ V l i q . i s : %1 . 4 f mˆ 3 .   \n ’ , V l i q ) ;

27   printf ( ’ ( i i ) The Ma ss a nd Volu me o f v a p ou r i s :   \n ’ ) ;

28   printf ( ’ Mvap . i s : %1 . 3 f kg .   \n ’ , M v a p ) ;

29   printf ( ’ Vvap . i s : %1 . 4 f mˆ 3.   \n ’ , V v a p ) ;

Scilab code Exa 4.3  Example 3

24

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1   clc

2   clear3   //DATA GIVEN4   V = 0 . 0 5 ;   // volume o f v e s s e l i n

mˆ35   M f = 1 0 ;   // mass o f l i q u i d i n

kg6   T = 2 4 5 ;   / / temp . i n d eg

c e l s i u s7

8   / / f rom stea m t a b l e s , c o r r es p o n d i ng t o 2 45 degc e l s i u s

9   P s a t = 3 6 . 5 ;   / / b a r10   v f = 0 . 0 0 1 2 3 9 ;   //mˆ3/kg11   v g = 0 . 0 5 4 6 ;   //mˆ3/kg12   h f = 1 0 6 1 . 4 ;   / / k J / k g13   h f g = 1 7 4 0 . 2 ;   / / k J / k g14   s f = 2 . 7 4 7 4 ;   //kJ/kgK15   s f g = 3 . 3 5 8 5 ;   //kJ/kgK16

17   V f = M f * v f ;   // v olume o f l i q u i d18   V g = V - V f ;   / / v ol um e o f v ap o ur19   M g = V g / v g ;

  / / ma ss o f v a po ur20   m = M f + M g ;   // t o t a l mass o f  m i x t u r e

21

22   x = M g / ( M g + M f ) ;   // q u a l i t y o f t hem i x t u r e

23   v f g = v g - v f ;

24   v = v f + x * v f g ;   // s p e c i f i c volume25

26   h = h f + x * h f g ;   // s p e c i f i c en th al py27

28   s = s f + x * s f g ;   // s p e c i f i c en tr op y29

30   u = h - P s a t * 1 0 ^ 5 * v / 1 0 ^ 3 ;   / / s p e c i f i c i n t e r n a le n e r g y

31

25

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32

33   printf ( ’ ( i ) The P r e s s u r e i s : %2 . 1 f b ar .   \n ’ , P s a t ) ;34   printf ( ’ ( i i ) The ma ss m i s : %2 . 3 f k g .   \n ’ , m ) ;

35   printf ( ’ ( i i i ) The S p e c i f i c v ol um e v i s : %1 . 6 f mˆ 3/ k g.   \n ’ , v ) ;

36   printf ( ’ ( i v ) The S p e c i f i c e nt ha l p y h i s : %4 . 2 f kJ /kg .   \n ’ , h ) ;

37   printf ( ’ ( v ) The S p e c i f i c e n tr o py s i s : %1 . 4 f kJ /kgK.   \n ’ , s ) ;

38   printf ( ’ ( v i ) The S p e c i f i c i n t e r n a l e ne rg y u i s : %4. 2 f k J / kg .   \n ’ , u ) ;

39

40   //NOTE:41   / / t h e r e i s s l i g h t v a r i a t i o n i n a ns we r s o f book due

t o r o un di ng o f f o f t h e v a l u es i n t he book

Scilab code Exa 4.4  Example 4

1   clc

2   clear

3   //DATA GIVEN4   M w = 2 ;   // mass o f w at er t o be

c o nv e rt e d t o s team i n kg5   T w = 2 5 ;   / / temp . o f w at er i n

deg c e l s i u s6   p = 5 ;   / / p r e s s u r e7   x = 0 . 9 ;   // d r yn e s s f r a c t i o n8

9   / / At 5 b ar , f ro m s te am t a b l e s10   h f = 6 4 0 . 1 ;   / / k J / k g

11   h f g = 2 1 0 7 . 4 ;   / / k J / k g12

13   h = h f + x * h f g ;   / / s p e c i f i c e n t h a l p y (abov e 0 deg c e l s i u s )

14   h s = 1 * 4 . 1 8 * ( T w - 0 ) ;   // s e n s i b l e h ea t

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a s s o c i a t e d w i t h i kg o f w a t e r

15   h n e t = h - h s ;   // n et q u a nt i t y o f  h ea t t o be s u pp l i e d p er kg o f w a t e r16   H t o t a l = M w * h n e t ;   / / t o t a l amount o f  

h ea t t o be s u p p l i e d17

18   printf ( ’ The T ot al amount o f h ea t t o be s u p p l i e d i s :%4. 2 f k J . ’ , H t o t a l ) ;

Scilab code Exa 4.5  Example 5

1   clc

2   clear

3   //DATA GIVEN4   m = 4 . 4 ;   // mass o f s tea m t o be

p ro du ce d i n kg5   p = 6 ;   / / p r e s s u r e o f s te am6   T s u p = 2 5 0 ;   / / temp . o f s te am i n

deg . c e l s i u s7   T w = 3 0 ;   / / temp . o f w at er i n

deg c e l s i u s8   C p s = 2 . 2 ;   // s p e c i f i c he at of  

s te am i n kJ / kg9

10   / / At 6 b ar , f ro m s te am t a b l e s11   T s = 1 5 8 . 8 ;   // d eg . c e l s i u s12   h f = 6 7 0 . 4 ;   / / k J / k g13   h f g = 2 0 8 5 ;   / / k J / k g14   // s i n c e t he g i v en temp . 250 deg c e l s i u s i s g r e a t e r

t han 1 5 8. 8 deg c e l s i u s , steam i s s up e r he at e d

1516   h s u p = h f + h f g + C p s * ( T s u p - T s ) ;   // e n th a lp y o f 1 kgs u p er g e at e d stea m r ec ko n ed from 0 d eg . c e l s i u s

17   h s = 1 * 4 . 1 8 * ( T w - 0 ) ;   // s e n s i b l e h ea ta s s o c i a t e d w i t h i kg o f w a t e r

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18   h n e t = h s u p - h s ;   // n et q u a nt i t y o f  

h ea t t o be s u pp l i e d p er kg o f w a t e r19   H t o t a l = m * h n e t ;   / / t o t a l amount o f  h ea t t o be s u p p l i e d

20

21   printf ( ’ The T ot al amount o f h ea t t o be s u p p l i e d i s :%4. 1 f k J . ’ , H t o t a l ) ;

Scilab code Exa 4.6  Example 6

1   clc

2   clear

3   //DATA GIVEN4   V = 0 . 1 5 ;   / / v ol um e o f w et s te am

i n m ˆ 35   p = 4 ;   // p r e s s u r e o f wet

stea m i n b ar6   x = 0 . 8 ;   // d r yn e s s f r a c t i o n7

8   / / At 4 b ar , f ro m s te am t a b l e s

9   v g = 0 . 4 6 2 ;   //mˆ3/kg10   h f = 6 0 4 . 7 ;   / / k J / k g11   h f g = 2 1 3 3 ;   / / k J / k g12

13   r h o = 1 / ( x * v g ) ;   / / d e n s i t y i n kg /mˆ 314   m = r h o * V ;   // mass o f 0 . 1 5 mˆ3 o f  

steam15

16   H t o t a l = ( r h o * 1 ) * ( h f + x * h f g ) ;   // t o t a l h ea t o f 1 mˆ3o f s team whi ch h as a mass o f r ho ( 2 . 7 0 5 6 ) kg

1718   printf ( ’ ( i ) The Mass o f 0 . 1 5 mˆ 3 o f s te am i s : %1 . 4 f  kg .   \n ’ , m ) ;

19   printf ( ’ ( i i ) The T o t a l h e a t o f 1 mˆ 3 o f s te am w hi chh as a mass o f 2 . 7 05 6 kg i s : %4 . 2 f kJ .   \n ’ , H t o t a l )

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;

Scilab code Exa 4.7  Example 7

1   clc

2   clear

3   //DATA GIVEN4   m = 1 0 0 0 ;   / / ma ss o f s te am

g e n er a t ed i n kg / h r

5   p = 1 6 ;   / / p r e s s u r e o f s te ami n b ar6   x = 0 . 9 ;   // d r yn e s s f r a c t i o n7   T s u p = 3 8 0 + 2 7 3 ;   / / t em p . o f  

s u p e r he a t e d s te am i n K8   T f w = 3 0 ;   / / temp . o f f e e d w at er

i n deg . c e l s i u s9   C p s = 2 . 2 ;   // s p e c i f i c he at of  

s te am i n kJ / kg10

11   / /At 1 6 b ar , f ro m s te am t a b l e s

12   T s = 2 0 1 . 4 + 2 7 3 ;   / / i n K13   h f = 8 5 8 . 6 ;   / / k J / k g14   h f g = 1 9 3 3 . 2 ;   / / k J / k g15

16   H s = m * [ ( h f + x * h f g ) - 1 * 4 .1 8 7 * ( T fw - 0 ) ] ;   // hea ts u p p li e d t o f e ed w at er p er hr t o p ro du ce wetsteam

17   H a = m * [ ( 1 - x ) * h f g + C p s * ( T s u p - T s ) ] ;   // hea ta bs o rb ed by s u p e r h ea t e r p er h ou r

18

19   printf ( ’ ( i ) The Heat s u p p l i e d t o f e e d w at er p er h ou rt o p r od u ce wet s te am i s : %4 . 2 f   ∗1 0 ˆ 3 k J .   \n ’ ,(Hs

/ 1 0 0 0 ) ) ;

20   printf ( ’ ( i i ) The H ea t a b s o r be d by s u p e r h e a t e r p e rh ou r i s : %3 . 2 f   ∗1 0 ˆ 3 k J .   \n ’  , ( H a / 1 0 0 0 ) ) ;

29

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Scilab code Exa 4.8  Example 8

1   clc

2   clear

3

4   / / At 0 . 7 5 b a r . From s te am t a b l e s ,5   / /At 1 00 deg c e l s i u s6   T 1 = 1 0 0 ;   // deg c e l s i u s

7   h s u p 1 = 2 6 7 9 . 4 ;   / / k J / k g8   / /At 1 50 deg c e l s i u s9   T 2 = 1 5 0 ;   // deg c e l s i u s

10   h s u p 2 = 2 7 7 8 . 2 ;   / / k J / k g11   C p s 1 = ( h s u p 2 - h s u p 1 ) / ( T 2 - T 1 ) ;

12

13   / / At 0 . 5 b a r . From s te am t a b l e s ,14   / /At 3 00 deg c e l s i u s15   T 3 = 3 0 0 ;   // deg c e l s i u s16   h s u p 3 = 3 0 7 5 . 5 ;   / / k J / k g17   / /At 4 00 deg c e l s i u s18   T 4 = 4 0 0 ;   // deg c e l s i u s19   h s u p 4 = 3 2 7 8 . 9 ;   / / k J / k g20   C p s 2 = ( h s u p 4 - h s u p 3 ) / ( T 4 - T 3 ) ;

21

22   printf ( ’ ( i ) The mean s p e c i f i c h e a t f o r s u p e r h e a t e dsteam   \n ( At 0 . 7 5 bar , b e tw e en 100 and 150deg c e l s i u s ) i s : %1 . 3 f .   \n ’ , C p s 1 ) ;

23   printf ( ’ ( i i ) The mean s p e c i f i c h e a t f o r s u p e r h e a t e dsteam   \n ( At 0 .5 bar , b e tw e en 300 and 400

deg c e l s i u s ) i s : %1 . 3 f .   \n ’ , C p s 2 ) ;

Scilab code Exa 4.9  Example 9

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1   clc

2   clear3   //DATA GIVEN4   m = 1 . 5 ;   / / mass o f s te am i n

c oo k e r i n kg5   p 1 = 5 ;   / / p r e s s u r e o f s te am

i n b ar6   x 1 = 1 ;   // i n i t i a l dr yn es s

f r a c t i o n o f steam7   x 2 = 0 . 6 ;   // f i n a l d r yn e ss

f r a c t i o n o f steam8

9   / / At 5 b ar , f ro m s te am t a b l e s10   T s 1 = 1 5 1 . 8 + 2 7 3 ;   / / i n K11   h f 1 = 6 4 0 . 1 ;   / / k J / k g12   h f g 1 = 2 1 0 7 . 4 ;   / / k J / k g13   v g 1 = 0 . 3 7 5 ;   //mˆ3/kg14

15   V 1 = m * v g 1 ;   //volume o f p r e s s u r e c o ok e r i n mˆ3

16   u 1 = ( h f 1 + h f g 1 ) - ( p 1 * 1 0 ^ 5 ) * ( v g 1 * 1 0 ^ - 3 ) ;   //i n t e r n a l e ne rg y o f s tea m p er kg a t i n i t i a l p o i nt

117   //V1=V218   //V1=m∗ [(1 − x2 ) ∗ vf2+x2∗vg2 ] // v f 2

i s n e g l i g i b l e19   v g 2 = V 1 / x 2 / 1 . 5 ;

20

21   / / f ro m s te am t a b l e s c o r e e s p o n d i n g t o v g2 = 0 .6 25 mˆ 3/kg

22   p 2 = 2 . 9 ;

23   T s 2 = 1 3 2 . 4 + 2 7 3 ;   / / i n K24   h f 2 = 5 5 6 . 5 ;   / / k J / k g

25   h f g 2 = 2 1 6 6 . 6 ;   / / k J / k g26

27   u 2 = ( h f 2 + x 2 * h f g 2 ) - ( p 2 * 1 0 ^ 5 ) * x 2 * ( v g 2 * 1 0 ^ - 3 ) ;   //i n t e r n a l e n e r g y o f steam p e r kg a t f i n a l p oi nt 2

28

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29   h n e t = u 2 - u 1 ;   // hea t

t r a n s f e r r e d a t c o ns t a n t volume p er kg30   H t o t a l = m * h n e t ;   //t o t a l h e at t r a n s f e r r e d

31   //−ve s i gn i n d i c a t e s t ha t h ea t h as be en r e j e c t e d32   H r e j = - 1 * H t o t a l ;

33

34   printf ( ’ ( i ) The P r e s su r e a t new s t a t e i s : %1 . 1 f b ar.   \n ’ , p 2 ) ;

35   printf ( ’ The Te mper at ur e a t new s t a t e i s : %3 . 1 f  deg . c e l s i u s o r %3 . 1 f K.   \n ’ ,(Ts2 -273) ,Ts2) ;

36   printf ( ’ ( i i ) The T o t a l h e a t t o b e REJECTED i s : %4 . 2

f k J . ’ , H r e j ) ;

Scilab code Exa 4.10  Example 10

1   clc

2   clear

3   //DATA GIVEN4   V = 0 . 9 ;   // c a p a c i t y o f  

s p h e r i c a l v e s s e l i n mˆ35   p 1 = 8 ;   // p r e s s u r e o f s te am

i n b ar6   x 1 = 0 . 9 ;   // d r yn e ss f r a c t i o n

o f s tea m7   p 2 = 4 ;   // p r e s s u r e o f s te am

a f t e r blow o f f i n b ar8   p 3 = 3 ;   // f i n a l p r e s s u re o f  

stea m i n b ar9

10   / / At 8 b ar , f ro m s te am t a b l e s11   h f 1 = 7 2 0 . 9 ;   / / k J / k g12   h f g 1 = 2 0 4 6 . 5 ;   / / k J / k g13   v g 1 = 0 . 2 4 0 ;   //mˆ3/kg14

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15   m 1 = V / ( x 1 * v g 1 ) ;   // m ass o f s te am i n

t h e v e s s e l i n kg16

17   h 1 = h f 1 + x 1 * h f g 1 ;   / / e n t h a l p y o f s te amb e f o r e b lo wi ng o f f ( p er kg )

18   // e n th a lp y o f stea m b e f o r e b lo wi ng o f f ( p er kg ) =e nt ha l p y o f steam a f t e r b lo wi ng o f f ( p er kg )

19   h 2 = h 1 ;

20   //h2=hf2+x2∗ h f g 221   / / At 4 b ar , f ro m s te am t a b l e s22   h f 2 = 6 0 4 . 7 ;   / / k J / k g23   h f g 2 = 2 1 3 3 ;   / / k J / k g

24   v g 2 = 0 . 4 6 2 ;   //mˆ3/kg25   x 2 = ( h 2 - h f 2 ) / h f g 2 ;   // d r yn e ss f r a c t i o n

a t 226

27   m 2 = V / ( x 2 * v g 2 ) ;   // m ass o f s te am i nt h e v e s s e l i n kg

28   m = m 1 - m 2 ;   / / ma ss o f s te amblown o f f i n kg

29

30   / /As i t i s c o ns t an t volume c o ol i ng , x2∗v g 2 ( a t 4 b a r )

=x3∗v g 3 ( a t 3 b a r )31   / / At 3 b ar , f ro m s te am t a b l e s32   h f 3 = 5 6 1 . 4 ;   / / k J / k g33   h f g 3 = 2 1 6 3 . 2 ;   / / k J / k g34   v g 3 = 0 . 6 0 6 ;   //mˆ3/kg35

36   x 3 = x 2 * v g 2 / v g 3 ;

37   h 3 = h f 3 + x 3 * h f g 3 ;

38

39   / / h e at l o s t d u r in g c o o l i n g , Q l o st=m( u3−u2 )40   u 2 = h 2 - p 2 * 1 0 ^ 5 * x 2 * v g 2 * 1 0 ^ - 3 ;

41   u 3 = h 3 - p 3 * 1 0 ^ 5 * x 3 * v g 3 * 1 0 ^ - 3 ;42   Q l o s t = m * ( u 3 - u 2 ) ;

43

44   printf ( ’ ( i ) The Mass o f o f s team blown o f f i s : %1 . 3f kg .   \n ’ , m ) ;

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45   printf ( ’ ( i i ) The D ry n es s f r a c t i o n o f steam i n t he

v e s s e l a f t e r c o o l i n g i s : %1 . 4 f .   \n ’ , x 3 ) ;46   printf ( ’ ( i i i ) The Hea t l o s t d u r i ng c o o l i n g i s : %3 . 2 f  kJ .   \n ’  , ( - Q l o s t ) ) ;

47

48   //NOTE:49   //T he ans w e r s of m1, x 3 ar e INCORRECT i n t he book ,50   / / t h u s , t h e a n s w e r s o f m, x 3 a nd Q l o s t a r e INCORRECT

i n t he book51   // w hi le , t he v a l ue s o bt ai ne d h er ( i n s c i l a b ) a re

CORRECT.

Scilab code Exa 4.11  Example 11

1   clc

2   clear

3   //DATA GIVEN4   p = 8 ;   / / p r e s s u r e o f s te am

i n b ar5   x = 0 . 8 ;   // d r yn e s s f r a c t i o n

67   / / At 8 b ar , f ro m s te am t a b l e s8   v g = 0 . 2 4 0 ;   //mˆ3/kg9   h f g = 2 0 4 6 . 5 ;   / / k J / k g

10

11   W e = p * 1 0 ^ 5 * x * v g / 1 0 0 0 ;   / / e x t e r n a l wo rk d on ed ur in g e v ap o ra t i o n i n kJ

12   L H i = x * h f g - W e ;   // I n t e r n a l l a t e n th ea t i n kJ

13

14   printf ( ’ ( i ) The E x t e rn a l work d on e d u r in ge v a p o r a t i o n i s : %3 . 1 f kJ .   \n ’ , W e ) ;

15   printf ( ’ ( i i ) The I n t e r n a l l a t e n t h ea t i s : %4 . 1 f kJ .\n ’ , L H i ) ;

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Scilab code Exa 4.12  Example 12

1   clc

2   clear

3   //DATA GIVEN4   p = 1 0 ;   / / p r e s s u r e o f steam ,

p 1=p 2 i n b a r5   x 1 = 0 . 8 5 ;   // d r yn e s s f r a c t i o n6   V 1 = 0 . 1 5 ;   / / vo lu me o f s te am i n

mˆ37   T s u p 2 = 3 0 0 + 2 7 3 ;   / / temp . o f s te am i n K8   C p s = 2 . 2 ;   // s p e c i f i c he at of  

s te a m i n k J /kgK9

10   / /At 1 0 b ar , f ro m s te am t a b l e s11   v g 1 = 0 . 1 9 4 ;   //mˆ3/kg12   h f g 1 = 2 0 1 3 . 6 ;   / / k J / k g13   T s 1 = 1 7 9 . 9 + 2 7 3 ;   / / i n K14   m = V 1 / ( x 1 * v g 1 ) ;   / / ma ss o f s te am

i n kg15   h n e t = ( 1 - x 1 ) * h f g 1 + C p s * ( T s u p 2 - T s 1 ) ;   / / h e at s u p p l i e d

p er kg o f stea m16   H t o t a l = m * h n e t ;   // t o t a l h ea t

s u p p l i e d17

18   / / E x t e r n a l wo rk d on e d u r i n g t h e p r o c e s s We=p ∗( v s u p 2−x∗vg1 )

19   // s i n c e p1=p2=p ,20   //vg1/Ts1=vsup2/Tsup221   v s u p 2 = v g 1 * T s u p 2 / T s 1 ;

22   W e = p * 1 0 ^ 5 * ( v s u p 2 - x 1 * v g 1 ) * 1 0 ^ - 3 ;

23   h p = W e / h n e t ;   //% o f t o t a lh ea t s u p p li e d ( p er kg ) which a pp ea rs a s e x t e r na lwork

35

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24

25   printf ( ’ ( i ) The T ot al h ea t s u p p l i e d i s : %3 . 1 f kJ .   \n ’ , H t o t a l ) ;

26   printf ( ’ ( i i ) The P er ce nt ag e o f t o t a l h ea t s u p p l i e d( p er kg ) wh ich a p pe ar s a s e x t e r n a l work i s : %2 . 1 f  

p e r c e n t .   \n ’  , ( h p * 1 0 0 ) ) ;

Scilab code Exa 4.13  Example 13

1   clc2   clear

3   //DATA GIVEN4   p = 1 8 ;   / / p r e s s u r e o f s te am5   x = 0 . 8 5 ;   // d r yn e s s f r a c t i o n6

7   / /At 1 8 b ar , f ro m s te am t a b l e s8   h f = 8 8 4 . 6 ;   / / k J / k g9   h f g = 1 9 1 0 . 3 ;   / / k J / k g

10   v g = 0 . 1 1 0 ;   //mˆ3/kg11   u f = 8 8 3 ;   / / k J / k g

12   u g = 2 5 9 8 ;   / / k J / k g13

14   v = x * v g ;   // s p e c i f i c volume of  w et s t e am

15   h = h f + x * h f g ;   // s p e c i f i c en th al pyo f wet s te am

16   u = ( 1 - x ) * u f + x * u g ;   / / s p e c i f i c i n t e r n a le n er g y o f wet s te am

17

18   printf ( ’ ( i ) The S p e c i f i c vo lu me v i s : %1 . 4 f mˆ 3/ k g .

\n ’ , v ) ;19   printf ( ’ ( i i ) The S p e c i f i c e nt ha l p y h i s : %4 . 2 f kJ /kg .   \n ’ , h ) ;

20   printf ( ’ ( i i i ) The S p e c i f i c i n t e r n a l e ne rg y u i s : %4. 2 f k J / kg .   \n ’ , u ) ;

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Scilab code Exa 4.14  Example 14

1   clc

2   clear

3   //DATA GIVEN4   p = 7 ;   / / p r e s s u r e o f s te am5   h = 2 5 5 0 ;   / / e n t h a l p y o f s te am6

7   / / At 7 b ar , f ro m s te am t a b l e s8   h f = 6 9 7 . 1 ;   / / k J / k g9   h f g = 2 0 6 4 . 9 ;   / / k J / k g

10   v g = 0 . 2 7 3 ;   //mˆ3/kg11   u f = 6 9 6 ;   / / k J / k g12   u g = 2 5 7 3 ;   / / k J / k g13

14   h g = h f + h f g ;

15   / /At 7 b ar , hg =2762 kJ / kg , h en ce s i n c e a c t u a le n th a lp y i s g i ve n a s 2 55 0 kJ /kg , t he stea m mustbe i n wet va po ur s t a t e

16   / / s p e c i f i c e n t h a l p y o f w et s te am , h=h f +x∗ h f g17   x = ( h - h f ) / h f g ;   // d r yn e s s f r a c t i o n18   v = x * v g ;   // s p e c i f i c volume of  

w et s t e am19   u = ( 1 - x ) * u f + x * u g ;   / / s p e c i f i c i n t e r n a l

e n er g y o f wet s te am20

21   printf ( ’ ( i ) The D ry ne ss f r a c t i o n x i s : %1 . 3 f .   \n ’ ,x

) ;

22   printf ( ’ ( i i ) The S p e c i f i c v ol ume v i s : %1 . 4 f mˆ 3/ k g

.   \n ’ , v ) ;23   printf ( ’ ( i i i ) The S p e c i f i c i n t e r n a l e ne rg y u i s : %4

. 2 f k J / kg .   \n ’ , u ) ;

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Scilab code Exa 4.15  Example 15

1   clc

2   clear

3   //DATA GIVEN4   p = 1 2 0 ;   / / p r e s s u r e o f s te am5   v = 0 . 0 1 7 2 1 ;   // s p e c i f i c volume of  

steam6

7   / /At 1 20 ba r , fr om s te am t a b l e s8   v g = 0 . 0 1 4 3 ;   //mˆ3/kg9   / / s i n c e vg<v , t he s team i s s u pe r he a te d

10   / / s o fro m s u p er h ea t t a b l e s a t 1 20 b ar and v = 0. 01 72 1mˆ3/kg

11   T = 3 5 0 ;   // d eg . c e l s i u s12   h = 2 8 4 7 . 7 ;   // s p e c i f i c en th al py

o f s tea m13   u = h - p * 1 0 ^ 5 * v / 1 0 ^ 3 ;   / / s p e c i f i c i n t e r n a l

e n er g y o f s te am

1415   printf ( ’ ( i ) The T em pe ra tu re i s : %3 . 0 f d eg c e l s i u s .

\n ’ , T ) ;

16   printf ( ’ ( i i ) The S p e c i f i c e nt ha l p y h i s : %4 . 1 f kJ /kg .   \n ’ , h ) ;

17   printf ( ’ ( i i i ) The S p e c i f i c i n t e r n a l e ne rg y u i s : %4. 2 f k J / kg .   \n ’ , u ) ;

Scilab code Exa 4.16  Example 16

1   clc

2   clear

3   //DATA GIVEN

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4   p = 1 4 0 ;   / / p r e s s u r e o f s te am

5   h = 3 0 0 1 . 9 ;   // s p e c i f i c en th al pyo f s tea m6

7   / /At 1 40 ba r , fr om s te am t a b l e s8   h g = 2 6 4 2 . 4 ;

9   / / s i n c e hg<h , t he s team i s s u pe r he a te d10   / / s o fro m s u p er h ea t t a b l e s a t 1 40 b ar and h = 30 01 .9

k J /k g11   T = 4 0 0 ;   // d eg . c e l s i u s12   v = 0 . 0 1 7 2 2 ;   // s p e c i f i c volume of  

steam

13   u = h - p * 1 0 ^ 5 * v / 1 0 ^ 3 ;   / / s p e c i f i c i n t e r n a le n er g y o f s te am

14

15   printf ( ’ ( i ) The T em pe ra tu re i s : %3 . 0 f d eg c e l s i u s .\n ’ , T ) ;

16   printf ( ’ ( i i ) The S p e c i f i c v ol ume v i s : %1 . 5 f mˆ 3/ k g.   \n ’ , v ) ;

17   printf ( ’ ( i i i ) The S p e c i f i c i n t e r n a l e ne rg y u i s : %4. 2 f k J / kg .   \n ’ , u ) ;

Scilab code Exa 4.17  Example 17

1   clc

2   clear

3

4   p 1 = 1 0 ;   // p r e s s u r e i nb ar

5   / /At 1 0 b ar and 3 00 deg c e l s i u s , fro m s team t a b l e s

o f s u p e r he a t e d s te am6   h s u p = 3 0 5 1 . 2   / / k J / k g7   T s u p = 3 0 0 + 2 7 3 ;   / / temp . o f s te a m

i n K8   / /At 1 0 b ar and 3 00 deg c e l s i u s , fro m s team t a b l e s

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o f dr y s a t u r a t ed stea m

9   T s = 1 7 9 . 9 + 2 7 3   / / temp . o f s te a mi n K10   v g = 0 . 1 9 4 ;   //mˆ3/kg11

12   / / By v g / Ts = v s u p / Ts up13   v s u p = v g * T s u p / T s ;

14   u 1 = h s u p - p 1 * 1 0 ^ 5 * v s u p / 1 0 ^ 3 ;

15

16   p 2 = 1 . 4 ;   / /new p r e s s u r ei n b ar

17   x 2 = 0 . 8 ;   / / d r y n e s s

f r a c t i o n18   // At 1 . 4 bar , fr om stea m t a b l e s19   h f 2 = 4 5 8 . 4 ;   / / k J / k g20   h f g 2 = 2 2 3 1 . 9 ;   / / k J / k g21   v g 2 = 1 . 2 3 6 ;   //mˆ3/kg22   h 2 = h f 2 + x 2 * h f g 2 ;   / / e n t h a l p y o f  

wet s te am ( a f t e r e x p an s i o n )23   u 2 = h 2 - p 2 * 1 0 ^ 5 * x 2 * v g 2 / 1 0 ^ 3 ;   / / i n t e r n a l

e ne rg y o f t h i s steam24   D u = u 2 - u 1 ;   / / c ha ng e i n

i n t e r n a l e ne rg y p e r kg25

26   printf ( ’ ( i ) The I n t e r n a l e ne rg y o f s u pe rh e a t eds te am a t 1 0 b ar i s : %4 . 1 f kJ / kg .   \n ’ , u 1 ) ;

27   printf ( ’ ( i i ) The Change i n i n t e r n a l e ne rg y p er kgi s : %2 . 1 f kJ .   \n ’ , D u ) ;

28   printf ( ’ ( N eg at iv e s i g n i n d i c a t e s DECREASE ini n t e r n a l e ne rg y . ) ’   ) ;

Scilab code Exa 4.18  Example 18

1   clc

2   clear

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Scilab code Exa 4.19  Example 19

1   clc

2   clear

3   //DATA GIVEN4   p = 2 0 ;   // p r e s s u r e i n t he

b o i l e r s and m ain i s 20 b a r5   T b s = 3 5 0 ;   / / t e m p e r a tu r e o f s te am

i n b o i l e r w i t h s u pe r h e a t er i n deg . c e l s i u s6   T m = 2 5 0 ;   / / t e m p e r a tu r e o f s te am

i n t he main i n deg . c e l s i u s7   C p s = 2 . 2 5 ;   // s p e c i f i c he a t of  

s te am i n kJ / kg8

9   / /At 2 0 b ar , f ro m s te am t a b l e s10   T s = 2 1 2 . 4 ;   // d eg . c e l s i u s11   h f = 9 0 8 . 6 ;   / / k J / k g12   h g = 2 7 9 7 . 2 ;   / / k J / k g13   h f g = 1 8 8 8 . 6 ;   / / k J / k g14

15   / / B o i l e r B1−20 bar , 350 deg . c e l s i u s16   h 1 = h g + C p s * ( T b s - T s ) ;

17

18   //Main−20 bar , 250 d eg c e l s i u s19   h m = 2 * [ h g + C p s * ( T m - T s ) ] ;   // t o t a l h ea t o f  

2 kg o f s team i n t he stea m m ain20

21   / / B o i l e r B2−20 bar ,22   //h2=hf+x2∗ h f g23   //h2=hm−h124   x 2 = ( ( h m - h 1 ) - h f ) / h f g ;

25

26   printf ( ’ The Q ua l i t y o f steam i n t he B o i l e r w it ho ut

s u p e r h e a t e r i s : %1 . 3 f .   \n ’ , x 2 ) ;

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Scilab code Exa 4.20  Example 20

1   clc

2   clear

3   //DATA GIVEN4   m = 1 ;   // m ass o f wet

s te am i n kg5   p = 6 ;   // p r e s s u r e o f  

stea m i n b ar6   x = 0 . 8 ;   / / d r y n e s s

f r a c t i o n7

8   / / At 6 b ar , f ro m s te am t a b l e s9   T s = 1 5 8 . 8 + 2 7 3 ;   / / i n K

10   h f g = 2 0 8 5 ;   / / k J / k g11   s w e t = 4 . 1 8 * log ( T s / 2 7 3 ) + x * h f g / T s ;   / / e n t r o p y o f  

w et s t ea m i n k J /kgK12

13   printf ( ’ The E nt ro py o f we t s te am i s : %1 . 4 f kJ / kgK . ’ ,

s w e t ) ;

14

15   //NOTE;16

  // t h e e xa ct an s i s 5 . 7 7 94 , w hi l e i n TB i t i s g iv ena s 5 . 7 8 6 5 kJ / kgK

Scilab code Exa 4.21  Example 21

1   clc

2   clear

3   //DATA GIVEN

4   p 1 = 1 0 ;   / / i n i t i a l p r e s s u r e o f  s team i n b ar5   T s u p = 2 5 0 ;   // i n i t i a l t e m pe r at u r e

o f steam i n deg c e l s i u s6   p 2 = 0 . 2 ;   // f i n a l p r e s s u r e o f  

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stea m i n b ar

7   x 2 = 0 . 9 ;   // f i n a l d r yn e ssf r a c t i o n o f steam8

9   / /At 1 0 b ar , f ro m s te am t a b l e s10   h s u p = 3 2 6 3 . 9 ;   / / k J / k g11   s s u p = 7 . 4 6 5 ;   //kJ/kgK12   h 1 = h s u p ;

13   s 1 = s s u p ;

14

15   // At 0 . 2 bar , fr om stea m t a b l e s16   h f 2 = 2 5 1 . 5 ;   //k J /k h

17   h f g 2 = 2 3 5 8 . 4 ;   / / k J / k g18   s f 2 = 0 . 8 3 2 1 ;   //kJ/kgK19   s g 2 = 7 . 9 0 9 4 ;   //kJ/kgK20   h 2 = h f 2 + x 2 * h f g 2 ;

21   s f g 2 = ( s g 2 - s f 2 ) ;

22   s 2 = s f 2 + x 2 * s f g 2 ;

23

24   D h = h 1 - h 2 ;   // d ro p i n e n th a lp y25   D s = s 1 - s 2 ;   / / c ha ng e i n e n tr o p y26

27   printf ( ’ ( i ) The Drop i n e n t h al p y i s : %3 . 1 f kJ / kg .   \n ’ , D h ) ;

28   printf ( ’ ( i i ) The c h a n g e ( DECREASE ) i n e n t r o p y i s :%1. 4 f k J /kgK . ’ , D s ) ;

Scilab code Exa 4.22  Example 22

1   clc

2   clear3   //DATA GIVEN4   m = 1 ;   // mass o f s tea m i n kg5   p = 1 2 ;   / / p r e s s u r e o f s te am

i n b ar

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6   T s u p = 2 5 0 + 2 7 3 ;   / / temp . o f s te am i n K

7   C p s = 2 . 1 ;   // s p e c i f i c he at of  s te am i n kJ / kg8

9   / /At 1 2 b ar , f ro m s te am t a b l e s10   T s = 1 8 8 + 2 7 3 ;   / / i n K11   h f g = 1 9 8 4 . 3 ;   / / k J / k g12   s s u p = 4 . 1 8 * log ( T s / 2 7 3 ) + h f g / T s + C p s * log ( T s u p / T s ) ;

/ / e n t r o py o f w et s te am i n kJ / kgK13

14   printf ( ’ The E ntro py o f 1 kg o f s u pe r he a te d stea m a t12 ba r and 250 deg c e l s i u s i s : %1 . 3 f kJ /kg .   \n ’ ,

s s u p ) ;

Scilab code Exa 4.23  Example 23

1   clc

2   clear

3   //DATA GIVEN4   p = 5 ;   / / p r e s s u r e o f s te am

i n b ar5   M w t = 5 0 ;   // mass o f w at er i n

t he t a nk i n kg6   t 1 = 2 0 ;   // i n i t i a l temp . in

deg . c e l s i u s7   M s = 3 ;   / / amo unt o f s t ea m

c on d en s ed i n kg8   t 2 = 4 0 ;   / / f i n a l temp . i n d eg .

c e l s i u s9   W e = 1 . 5 ;   // w at e r e q u i v a l e n t o f  

t a nk i n kg10

11   / / At 5 b ar , f ro m s te am t a b l e s12   h f = 6 4 0 . 1 ;   / / i n k J / kg13   h f g = 2 1 0 7 . 4 ;   / / i n k J / kg

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14

15   M w = M w t + W e ;   // t o t a l mass o f w at eri n kg16   // h ea t l o s t by st ea m = h ea t g a in ed by w at er17   //Ms [ ( hf+xhfg ) −1∗4. 18∗( t2 −0) ]=Mw[ 1 ∗ 4 . 1 8 ∗ ( t 2−t1 ) ]18   x = [ M w * [ 1 * 4 . 1 8 * ( t 2 - t 1 ) ] / M s + 1 * 4 . 1 8 * ( t 2 - 0 ) - h f ] / h f g ;

// d r yn e s s f r a c t i o n19

20   printf ( ’ The D ry ne ss f r a c t i o n o f steam , x i s : %1 . 4 f . ’, x ) ;

Scilab code Exa 4.24  Example 24

1   clc

2   clear

3   //DATA GIVEN4   p = 1 . 1 ;   / / p r e s s u r e o f s te am

i n b ar5   x = 0 . 9 5 ;   // d r yn e s s f r a c t i o n6   M w t = 9 0 ;   // mass o f w at er i n

t he t a nk i n kg7   t 1 = 2 5 ;   // i n i t i a l temp . in

deg . c e l s i u s8   M t = 1 2 . 5 ;   // mass o f t an k i n kg9   c = 0 . 4 2 ;   // s p e c i f i c he at of  

m e ta l i n kJ / kgK10   t 2 = 4 0 ;   / / f i n a l temp . i n d eg .

c e l s i u s11

12   m 1 = M w t ;

13   m 2 = M t * c ;   // w at e r e q u i v a l e n t o f  v e s s e l14   M = m 1 + m 2 ;   // t o t a l mass o f w at er

i n kg15   // At 1 . 1 bar , fr om stea m t a b l e s

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16   h f = 4 2 8 . 8 ;   / / i n k J / kg

17   h f g = 2 2 5 0 . 8 ;   / / i n k J / kg18   // h ea t l o s t by st ea m = h ea t g a in ed by w at er19   //Ms [ ( hf+xhfg ) −1∗4. 18∗( t2 −0)]=M[1 ∗ 4 . 1 8 ∗ ( t 2−t1 ) ]20   M s = M * [ 1 * 4 . 1 8 * ( t 2 - t 1 ) ] / [ ( h f + x * h f g ) - 1 * 4 .1 8 * ( t 2 - 0 ) ] ;

// m ass o f s te am c o nd e ns e d i n kg21

22   printf ( ’ The Mass o f s te am c o nd e ns e d , Ms i s : %1 . 3 f  kg . ’ , M s ) ;

Scilab code Exa 4.25  Example 25

1   clc

2   clear

3   //DATA GIVEN4   / / c o n d i t i o n o f st eam b e f o r e t h r o t t l i n g5   p 1 = 8 ;   // p r e s s u r e i n b ar6   // c o n d i t i o n o f st eam a f t e r t h r o t t l i n g7   p 2 = 1 ;   // p r e s s u r e i n b ar8   T 2 = 1 1 5 + 2 7 3 ;   // temp . i n deg . c e l s i u s

9   T s u p 2 = T 2 ;10   / / At 1 b ar ,11   T s 2 = 9 9 . 6 + 2 7 3 ;

12   C p s = 2 . 1 ;   //kJ/kgK13

14   / /As t h r o t t l i n g i s a c on s ta n t e nt ha l p y p r o c e ss ,15   // h1=h2 . . . . . hf 1+x1∗ hgf1=hf2+hfg2+Cps(Tsup2−T s2)16

17   / /At 8 b ar , f ro m s te am t a b l e s ,18   h f 1 = 7 2 0 . 9 ;

19   h f g 1 = 2 0 4 6 . 5 ;20   / /At 1 b ar , f ro m s te am t a b l e s ,21   h f 2 = 4 1 7 . 5 ;

22   h f g 2 = 2 2 5 7 . 9 ;

23

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24   x 1 = [ h f 2 + h f g 2 + C p s * ( T s u p 2 - T s 2 ) - h f 1 ] / h f g 1 ;   //

d r y ne s s f r a c t i o n25

26   printf ( ’ The D ry ne ss f r a c t i o n o f stea m i n t he main ,x1 i s : %1 . 2 f . ’ , x 1 ) ;

Scilab code Exa 4.26  Example 26

1   clc

2   clear3   //DATA GIVEN4   M w = 2 ;   // m ass o f w at er

s e pa r at e d o ut i n kg5   M s = 2 0 . 5 ;   / / amount o f s te am (

c o nd e ns a te ) d i s c h a rg e d fro m t h r o t t l i n gc a l o r i m e t e r i n kg

6   T s u p 3 = 1 1 0 + 2 7 3 ;   / / temp . o f s t ea ma f e t r t h r o t t l i n g i n K

7   p 1 = 1 2 ;   // i n i t i a l pr e s su r eo f st eam i n ba r

8   p 3 = ( 7 6 0 + 5 ) / 1 0 0 0 * 1 . 3 3 6 6 ;   // f i n a l p r e s s u re o f  s te am i n b ar ( 1 mm o f Hg =1 .3 36 6 b ar )

9   C p s = 2 . 1 ;   //kJ/kgK10

11   p 2 = p 1 ;

12   / / At p 1=p2 =12 b ar , f ro m s te a m t a b l e s13   h f 2 = 7 9 8 . 4 ;   / / i n kJ / k g14   h f g 2 = 1 9 8 4 . 3 ;   / / i n kJ / k g15

16   / / At p3=1 b ar , f ro m s te am t a b l e s

17   T s 3 = 9 9 . 6 + 2 7 3 ;   / / i n K18   T s u p 3 = 1 1 0 + 2 7 3 ;   / / i n K19   h f 3 = 4 1 7 . 5 ;   / / i n kJ / k g20   h f g 3 = 2 2 5 7 . 9 ;   / / i n kJ / k g21

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22   // h2=h3 . . . . . hf 2+x2∗ hgf2=hf3+hfg3+Cps(Tsup3−T s3)

23   x 2 = [ h f 3 + h f g 3 + C p s * ( T s u p 3 - T s 3 ) - h f 2 ] / h f g 2 ;   //d ry ne ss f r a c t i o n x224

25   x 1 = ( x 2 * M s ) / ( M w + M s ) ;   //d r y ne s s f r a c t i o n o f steam s u pp l i e d , x1

26

27   printf ( ’ The Q u a l it y o f s te am s u p p l i e d , x1 i s : %1 . 2 f .’ , x 1 ) ;

Scilab code Exa 4.27  Example 27

1   clc

2   clear

3   //DATA GIVEN4   p 1 = 1 5 ;   // p r e s s u r e o f s te am

s am pl e i n b ar5   p 3 = 1 ;   // p r e s s u r e o f s te am

a t e x i t i n b a r6   T s u p 3 = 1 5 0 + 2 7 3 ;   / / t e m p e r a t u r e o s

steam a t t h e e x i t i n K7   M w = 0 . 5 ;   / / d i s c h a r g e f ro m

s e p a r at i n g c a l o r i m e t e r i n kg /min8   M s = 1 0 ;   / / d i s c h a r g e f ro m

t h r o t t l i n g c a l o r i m e t e r i n kg /min9

10   p 2 = p 1 ;

11   / / At p 1=p2 =15 b ar , f ro m s te a m t a b l e s12   h f 2 = 8 4 4 . 7 ;   / / i n kJ / k g13   h f g 2 = 1 9 4 5 . 2 ;   / / i n kJ / k g

1415   / /At p3=1 b ar and 1 50 d eg . c e l s i u s , f ro m s te amt a b l e s

16   h s u p 3 = 2 7 7 6 . 4 ;   / / i n kJ / k g17

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18   // h2=h3 . . . . . hf 2+x2∗ hgf2=hsup3

19   x 2 = [ h s u p 3 - h f 2 ] / h f g 2 ;   // d r yn e ss f r a c t i o nx220

21   x 1 = ( x 2 * M s ) / ( M w + M s ) ;   // q u a l i t y o f s teams u p p l i ed , x1

22

23   printf ( ’ The Q u a l it y o f s te am s u p p l i e d , x1 i s : %1 . 3 f .’ , x 1 ) ;

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Chapter 5

Heat Engines

Scilab code Exa 5.1  Example 1

1   clc

2   clear

3   //DATA GIVEN4   M s = 1 0 0 0 0 / 3 6 0 0 ;   // r a t e o f s team f l ow i n kg / s5   / / i n l e t t o t u r bi n e6   p 1 = 6 0 ;   // p r e s s u e i n b ar

7   T 1 = 3 8 0 ;   / / temp . i n d eg . c e l s i u s8

9   // e x i t from t ur bi ne , i n l e t t o c on de ns e r10   p 2 = 0 . 1 ;   // p r e s s u e i n b ar11   x 2 = 0 . 9 ;   / / q u a l i t y12   v 2 = 2 0 0 ;   // v e l o c i t y i n m/ s13

14   / / e x i t f ro m c o nd e ns e r , i n l e t t o pump15   p 3 = 0 . 0 9 ;   // p r e s s u e i n b ar16   // i t i s s a tu r a t ed

1718   / / e x i t from pump , i n l e t t o b o i l e r19   p 4 = 7 0 ;   // p r e s s u e i n b ar20

21   // e x i t from b o i l e r ,

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22   p 5 = 6 5 ;   // p r e s s u e i n b ar

23   T 5 = 4 0 0 ;   / / temp . i n d eg . c e l s i u s24

25   / / f o r c o n d en s e r ,26   t 1 = 2 0 ;   // i n l e t temp . i n deg . c e l s i u s27   t 2 = 3 0 ;   // e x i t temp . i n deg . c e l s i u s28

29   // At 60 b ar and 3 80 d eg . c e l s i u s , fro m s team t a b l e s30   h 1 = 3 0 4 3 . 0 + ( 3 1 7 7 . 2 - 3 0 4 3 . 0 ) / ( 4 0 0 - 3 5 0 ) * 3 0 ;   //By

i n t e r p o l a t i o n31

32   // At 0 . 1 bar , fr om stea m t a b l e s

33   h f 2 = 1 9 1 . 8 ;   / / i n k J / kg34   h f g 2 = 2 3 9 2 . 8 ;   / / i n k J / kg35   h 2 = h f 2 + x 2 * h f g 2 ;

36   P t = M s * ( h 1 - h 2 )   // p owe r o ut p ut o f  t he t u r b i n e i n kW

37

38   / /At 7 0 b ar , f ro m s te am t a b l e s39   h f 4 = 1 2 6 7 . 4 ;   / / i n k J / kg40   // At 60 b ar and 3 80 d eg . c e l s i u s , fro m s team t a b l e s41   h a = ( 3 1 7 7 . 2 + 3 1 5 8 . 1 ) / 2 ;   //By i n t e r p o l a t i o n

be tw e en 60 and 70 deg c e l s i u s42   Q 1 = M s * 3 6 0 0 * ( h a - h f 4 ) ;   // h ea t t r a n s f e rp e r hour i n t h e b o i l e r

43   // At 0 . 0 9 bar , fro m s tea m t a b l e s44   h f 3 = 1 8 3 . 3 ;   / / i n k J / kg45   Q 2 = M s * 3 6 0 0 * ( h 2 - h f 3 ) ;   // h ea t t r a n s f e r

p er hour i n t he c on de ns e r46

47   // h ea t l o s t by st ea m=h ea t g a in e d by t he c o o l i n gw a t e r

48   //Q2=Mw∗ 4 . 1 8 ∗ ( t 2−t 1 )

49   M w = Q 2 / 4 . 1 8 / 1 0 ;   // mass o f c o o l i n gw at er c i r c u l e t e d p er hour i n c on de ns er

50

51   // ( pi ) /4∗dˆ2=Ms∗x2∗vg252   / /d=d i am e te r o f t he p i pe c o n n ec t i ng t u r b i n e w it h

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c o n d e n s e r

53   C = 2 0 0 ;   // v e l o c i t y o f  s te am i n m/ s54   v g 2 = 1 4 . 6 7 ;   // s p e c i f i c volume

a t 0 . 1 ba r55   d = ( M s * x 2 * v g 2 / ( % p i / 4 ) / C ) ^ 0 . 5 ;

56

57   printf ( ’ ( i ) The Power o u tp ut o f t u r b i n e i s : %4 . 0 f  kW.   \n ’ , P t ) ;

58   printf ( ’ ( i i ) The Heat t r a n s f e r p er hour i n t heB o i l e r i s : %3 . 2 e kJ / h .   \n ’ , Q 1 ) ;

59   printf ( ’ The Heat t r a n s f e r p e r hour i n th e

C o n de n s er i s : %3 . 2 e k J /h .   \n ’ , Q 2 ) ;60   printf ( ’ ( i i i ) The Mass o f c o o l i n g w at er c i r c u l a t e d

p er h ou r i n t he c o nd e ns e r i s : %3 . 2 e kg / hr .   \n ’ , Mw

) ;

61   printf ( ’ ( i v ) The D ia me te r o f t he p i pe c o n n ec t i ngt u r b i n e w it h c o n d en s e r i s : %1 . 3 f m o r %3 . 0 f mm.   \n ’ , d , ( d * 1 0 0 0 ) ) ;

62

63   //NOTE:64   / / a n s o f Mw( 1 . 1 1 6 ∗1 0 ˆ 7 ) i s g iv en i n c o r r e c t i n t he

book .65   // t he c o r r e c t an s o f Mw i s = 5 . 1 7∗1 0 ˆ 5 kg / h .

Scilab code Exa 5.2  Example 2

1   clc

2   clear

3   //DATA GIVEN

4   p 1 = 1 5 ;   // s tea m s u pp ly p r e s s u r e i nb ar5   x 1 = 1 ;   // q u a l i t y o f s tea m6   p 2 = 0 . 4 ;   / / c o n d en s e r p r e s s u r e7

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8   // At 0 . 1 5 bar , fro m s tea m t a b l e s

9   T 1 = 1 9 8 . 3 + 2 7 3 ;   / / i n K10   h g 1 = 2 7 8 9 . 9 ;   / / i n k J / kg11   s g 1 = 6 . 4 4 0 6 ;   // i n k J /kgK12   // At 0 . 4 bar , fr om stea m t a b l e s13   T 2 = 7 5 . 9 + 2 7 3 ;   / / i n K14   h f 2 = 3 1 7 . 7 ;   / / i n k J / kg15   h f g 2 = 2 3 1 9 . 2 ;   / / i n k J / kg16   s f 2 = 1 . 0 2 6 1 ;   // i n k J /kgK17   s f g 2 = 6 . 6 4 4 8 ;   // i n k J /kgK18

19   E T A c a r n o t = ( T 1 - T 2 ) / T 1 ;   // C arnot e f f i c i e n c y

20   / / ETArankine=A d i a b a ti c o r i s e n t r o p i c h e at d ro p / h e ats u p p l i e d

21   //ETArankine=(hg1−h2) /( hg1−hf 2 )22   / / a s t he stea m e xp an ds i s e n t r o p i c a l l y , s 1=s 223   //sg1= sf 2+ x 2∗ s f g 224   x 2 = ( s g 1 - s f 2 ) / s f g 2 ;

25   h 2 = h f 2 + x 2 * h f g 2 ;

26   E T A r a n k i n e = ( h g 1 - h 2 ) / ( h g 1 - h f 2 ) ;   / / R a n k i n ee f f i c i e n c y

27

28   printf ( ’ ( i ) The Ca rnot e f f i c i e n c y i s : %1 . 4 f o r %2 . 2f p e r ce n t .   \n ’ , E T A c a rn o t , ( E T A c a r n o t * 1 0 0 ) ) ;

29   printf ( ’ ( i i ) The R ank ine e f f i c i e n c y i s : %1 . 4 f o r %2. 2 f p e r c e n t .   \n ’ , E T A r a n ki n e , ( E T A r a n k i n e * 1 0 0 ) ) ;

Scilab code Exa 5.3  Example 3

1   clc

2   clear3   //DATA GIVEN4   p 1 = 2 0 ;   // b o i l e r p r e s s u re i n b a r5   T 1 = 3 6 0 + 2 7 3 ;   / / temp . i n K6   p 2 = 0 . 0 8 ;   // b o i l e r p r e s s u re i n b a r

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7

8   // At 20 b ar and 3 60 deg . c e l s i u s , fro m s team t a b l e s9   h 1 = 3 1 5 9 . 3 ;   / / i n k J / kg10   s g 1 = 6 . 9 9 1 7 ;   // i n k J /kgK11

12   // At 0 . 0 8 bar , fro m s tea m t a b l e s13   h f 2 = 1 7 3 . 8 8 ;   / / i n k J / kg14   h f 3 = h f 2 ;

15   s f 2 = 0 . 5 9 2 6 ;   // i n k J /kgK16   s 3 = s f 2 ;

17   h f g 2 = 2 4 0 3 . 1 ;   / / i n k J / kg18   s g 2 = 8 . 2 2 8 7 ;   // i n k J /kgK

19   v f 2 = 0 . 0 0 1 0 0 8 ;   //mˆ3/kg20   s f g 2 = 7 . 6 3 6 1 ;   // i n k J /kgK21

22   / / a s t he stea m e xp an ds i s e n t r o p i c a l l y , s 1=s 223   //sg1= sf 2+ x 2∗ s f g 224   x 2 = ( s g 1 - s f 2 ) / s f g 2 ;

25   h 2 = h f 2 + x 2 * h f g 2 ;

26

27   //Wnet=Wturbine−Wpump28   //Wpump=hf4−hf 3=vf 3 ( p1−p2 )29   W p = v f 2 * ( p 1 - p 2 ) * 1 0 0 ;

30   h f 4 = W p + h f 3 ;

31   W t = h 1 - h 2 ;

32   W n e t = W t - W p ;

33   Q 1 = h 1 - h f 4 ;   / / i n k J / kg34   E T A c y c l e = W n e t / Q 1 ;   // c y c l e e f f i c i e n c y35

36   printf ( ’ ( i ) The Net work p er kg o f stea m i s : %3 . 2 f  kJ/ kg .   \n ’ , W n e t ) ;

37   printf ( ’ ( i i ) The C yc le e f f i c i e n c y i s : %1 . 3 f o r %2 . 1f p e r ce n t .   \n ’ , E T A c yc l e , ( E T A c y c l e * 1 0 0 ) ) ;

Scilab code Exa 5.4  Example 4

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1   clc

2   clear3   // g i v en s team t a b l e e x t r a c t4   p 1 = 8 0 ;   / / i n b a r5   t 1 = 2 9 5 . 1 ;   // i n deg . c e l s i u s6   v f 1 = 0 . 0 0 1 3 8 5 ;   //mˆ3/kg7   v g 1 = 0 . 0 2 3 5 ;   //mˆ3/kg8   h f 1 = 1 3 1 7 ;   / / i n k J / kg9   h f g 1 = 1 4 4 0 . 5 ;   / / i n k J / kg

10   h g 1 = 2 7 5 7 . 5 ;   / / i n k J / kg11   s f 1 = 3 . 2 0 7 3 ;   // in kJ/kgK12   s f g 1 = 2 . 5 3 5 1 ;   // in kJ/kgK

13   s g 1 = 5 . 7 4 2 4 ;   // in kJ/kgK14

15   p 2 = 0 . 1 ;   / / i n b a r16   t 2 = 4 5 . 8 4 ;   // i n deg . c e l s i u s17   v f 2 = 0 . 0 0 1 0 1 0 3 ;   //mˆ3/kg18   v g 2 = 1 4 . 6 8   //mˆ3/kg19   h f 2 = 1 9 1 . 9 ;   / / i n k J / kg20   h f 3 = h f 2 ;

21   h f g 2 = 2 3 9 2 . 3 ;   / / i n k J / kg22   h g 2 = 2 5 8 4 . 2 ;   / / i n k J / kg23   s f 2 = 0 . 6 4 8 8 ;

  // in kJ/kgK24   s f g 2 = 7 . 5 0 0 6 ;   // in kJ/kgK25   s g 2 = 8 . 1 4 9 4 ;   // in kJ/kgK26

27   E T A t = 0 . 9 ;   // steam t u r bi n e e f f i c i e n c y28   E T A p = 0 . 8 ;   // c o nde nsa t e pump

e f f i c i e n c y29

30   P 1 = 8 0 ;   / / i n b a r31   T 1 = 6 0 0 ;   // i n deg c e l s i u s32   / /At 80 b ar and 600 deg c e l s i u s

33   v 1 = 0 . 4 8 6 ;   //mˆ3/kg34   h 1 = 3 6 4 2 ;   / / k J / k g35   s 1 = 7 . 0 2 0 6 ;   //k J /k g/K36

37   / / a s t he stea m e xp an ds i s e n t r o p i c a l l y , s 1=s 2

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38   //sg1= sf 2+ x 2∗ s f g 2

39   x 2 = ( s 1 - s f 2 ) / s f g 2 ;40   h 2 = h f 2 + x 2 * h f g 2 ;

41   W t a = E T A t * ( h 1 - h 2 ) ;   // a c t u a l t u r b i n e work i n kJ/ kg

42   W p = v f 2 * ( p 1 - p 2 ) * 1 0 ^ 5 / 1 0 ^ 3 ; / / pump w or k i n k J / k g43   W p a = W p / E T A p ;   / / a c t u a l pump w or k i n k J / kg44   W n e t = W t a - W p a ;   // s p e c i f i c w or k i n k J /k g45   //ETAthermal=Wnet/Q146   //Q1=h1−h f 447   h f 4 = h f 3 + W p a ;

48   Q 1 = h 1 - h f 4 ;

49   E T A t h = W n e t / Q 1 ;50

51   printf ( ’ ( i ) The S p e c i f i c work ( Wnet ) i s : %4 . 2 f kJ /kg .   \n ’ , W n e t ) ;

52   printf ( ’ ( i i ) The Thermal e f f i c i e n c y i s : %1 . 3 f o r %2. 1 f p e r c e n t .   \n ’ ,ETAth ,(ETAth*100));

Scilab code Exa 5.5  Example 5

1   clc

2   clear

3   //DATA GIVEN4   p 1 = 2 8 ;   // p r e s s ur e a t 1 i n b ar5   p 2 = 0 . 0 6 ;   // p r e s s ur e a t 2 i n b ar6

7   / /At 2 8 b ar , f ro m s te am t a b l e s8   h 1 = 2 8 0 2 ;   / / i n k J / kg9   s 1 = 6 . 2 1 0 4 ;   // i n k J /kgK

1011   // At 0 . 0 6 bar , fro m s tea m t a b l e s12   h f 2 = 1 5 1 . 5 ;   / / i n k J / kg13   h f 3 = h f 2 ;

14   h f g 2 = 2 4 1 5 . 9 ;   / / i n k J / kg

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15   s f 2 = 0 . 5 2 1 ;   // i n k J /kgK

16   s f 3 = s f 2 ;17   s f g 2 = 7 . 8 0 9 ;   // i n k J /kgK18   v f 2 = 0 . 0 0 1 ;   //mˆ3/kg19

20

21   / / a s t he stea m e xp an ds i s e n t r o p i c a l l y , s 1=s 222   //sg1= sf 2+ x 2∗ s f g 223   x 2 = ( s 1 - s f 2 ) / s f g 2 ;

24   h 2 = h f 2 + x 2 * h f g 2 ;

25

26   //Wnet=Wturbine−Wpump

27   //Wpump=hf4−hf 3=vf 3 ( p1−p2 )28   W p = v f 2 * ( p 1 - p 2 ) * 1 0 ^ 5 / 1 0 ^ 3 ;

29   h f 4 = W p + h f 2 ;

30   W t = h 1 - h 2 ;

31   W n e t = W t - W p ;

32   Q 1 = h 1 - h f 4 ;   / / i n k J / kg33   E T A c y c l e = W n e t / Q 1 ;   // c y c l e e f f i c i e n c y34   w r = W n e t / W t ;   // work r a t i o35   s s c = 3 6 0 0 / W n e t ;   // s p e c i f i c st e am c onsumpt i on

in kg/kWh36

37   printf ( ’ ( i ) The C yc le e f f i c i e n c y i s : %1 . 4 f o r %2 . 2 f  p e r c e n t .   \n ’ , E T A c yc l e , ( E T A c y c l e * 1 0 0 ) ) ;

38   printf ( ’ ( i i ) The Work r a t i o i s : %1 . 3 f kJ / kg .   \n ’ , wr

) ;

39   printf ( ’ ( i i i ) The S p e c i f i c s te am c on su mp ti on i n kg /kWh i s : %1. 3 f kg/kWh.   \n ’ , s s c ) ;

Scilab code Exa 5.6  Example 6

1   clc

2   clear

3   //DATA GIVEN

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4   p 1 = 3 5 ;   // p r e s s u r e a t i n l e t t o

t u r b i n e i n b a r5   x 1 = 1 ;

6   p 2 = 0 . 2 ;   // p r e s s ur e a t e xh au st i n ba r7   m = 9 . 5 ;   // f l o w r a t e i n kg / s8

9   / /At 3 5 b ar , f ro m s te am t a b l e s10   h g 1 = 2 8 0 2 ;   / / i n k J / kg11   h 1 = h g 1 ;

12   s g 1 = 6 . 1 2 2 8 ;   // i n k J /kgK13

14   // At 0 . 2 bar , fr om stea m t a b l e s

15   h f 2 = 2 5 1 . 5 ;   / / i n k J / kg16   h f 3 = h f 2 ;

17   h f g 2 = 2 3 5 8 . 4 ;   / / i n k J / kg18   v f 2 = 0 . 0 0 1 0 1 7 ;   //mˆ3/kg19   s f 2 = 0 . 8 3 2 1 ;   // i n k J /kgK20   s f g 2 = 7 . 0 7 7 3 ;   // i n k J /kgK21

22   //Wnet=Wturbine−Wpump23   //Wpump=hf4−hf 3=vf 3 ( p1−p2 )24   W p = v f 2 * ( p 1 - p 2 ) * 1 0 ^ 5 / 1 0 ^ 3 ;

25   W p n e t = m * W p ;

26   h f 4 = W p + h f 3 ;

27

28   / / a s t he stea m e xp an ds i s e n t r o p i c a l l y , s 1=s 229   //sg1= sf 2+ x 2∗ s f g 230   x 2 = ( s g 1 - s f 2 ) / s f g 2 ;   / / d r y n e s s

f r a c t i o n31   h 2 = h f 2 + x 2 * h f g 2 ;

32   W t = h 1 - h 2 ;

33   W t n e t = m * W t ;

34   E T A r a n k i n e = ( h 1 - h 2 ) / ( h 1 - h f 2 ) ;   / / R a n k i n e

e f f i c i e n c y35   c h f = m * ( h 2 - h f 3 ) ;   / / c o n d e n s e r

h ea t f l ow36

37   printf ( ’ ( i ) The Pump Work i s : %2. 2 f kW.   \n ’ , W p n e t ) ;

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38   printf ( ’ ( i i ) The T u r bi n e Work i s : %2 . 2 f kW .   \n ’ ,

W t n e t ) ;39   printf ( ’ ( i i i ) The R an ki ne e f f i c i e n c y i s : %1 . 4 f o r %2. 2 f p e r c e n t .   \n ’ , E T A r a n ki n e , ( E T A r a n k i n e * 1 0 0 ) ) ;

40   printf ( ’ ( i v ) The C o nd en s er h e a t f l o w i s : %1 . 3 f kW .\n ’ , c h f ) ;

41   printf ( ’ ( v ) The d r y n es s a t t he end o f e xp an si on ,x2 i s : %1 . 3 f o r %2 . 1 f p e r c e n t .   \n ’ , x 2 , ( x 2 * 1 0 0 ) ) ;

42

43   //NOTE:44   / /The v al ue o f x2 i n t h e b ook i s g iv en a s 0 . 7 47 045   / / w hi l e t he e x a c t a ns i s 0 . 7 4 75 5

46   // and s o t he v a l ue s o f o t he r a ns we rs a r e v ar y i ng bysome u n i t s

Scilab code Exa 5.7  Example 7

1   clc

2   clear

3   //DATA GIVEN

4   h 1 2 = 8 4 0 ;   // A d i a b a t ic e n t ha l p y dr op , (h1−h2 ) i n kJ / kg

5   h 1 = 2 9 4 0 ;   // e n t ha l p y o f s te am s u p p l i e di n kJ / kg

6   p 2 = 0 . 1 ;   // b ack p r e s s ur e i n b ar7

8   // At 0 . 1 bar , fr om stea m t a b l e s9   h f = 1 9 1 . 8 ;   / / i n k J / kg

10   //ETArankine=(hg1−h2) /( hg1−hf 2 )11   E T A r a n k i n e = ( h 1 2 ) / ( h 1 - h f ) ;

12   W u s e = h 1 2 ;   // u s e f u l work done p er kg o f  s te am i n kJ / kg13   s s c = 1 / W u s e * 3 6 0 0 ;   // s p e c i f i c st e am c onsumpt i on14

15   printf ( ’ ( i ) The Ra nki ne e f f i c i e n c y i s : %1 . 4 f o r %2 . 2

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f p e r ce n t .   \n ’ , E T A r a n ki n e , ( E T A r a n k i n e * 1 0 0 ) ) ;

16   printf ( ’ ( i i ) The S p e c i f i c s te am c on su mp ti on i s : %1 . 3f kg/kWh.   \n ’ , s s c ) ;

Scilab code Exa 5.8  Example 8

1   clc

2   clear

3   //DATA GIVEN

4   I P = 3 5 ;   // p owe r d e v el o p ed by t h ee n g i n e i n kW5   m = 2 8 4 ;   // f l o w r a t e i n kg /h6   p 1 = 1 5 ;   // steam i n l e t p r e s s u re i n

b ar7   p 2 = 0 . 1 4 ;   // c o nd e ns e r p r e s s u r e i n b ar8

9   / /At 3 5 b ar and 25 deg c e l s i u s from steam t a b l e s10   h 1 = 2 9 2 3 . 3 ;   / / i n k J / kg11   s 1 = 6 . 7 0 9 ;   // in kJ/kgK12

13   // At 0 . 1 4 bar , fro m s tea m t a b l e s14   h f 2 = 2 2 0 ;   / / i n k J / kg15   h f 3 = h f 2 ;

16   h f g 2 = 2 3 7 6 . 6 ;   / / i n k J / kg17   s f 2 = 0 . 7 3 7 ;   // i n k J /kgK18   s f g 2 = 7 . 2 9 6 ;   // i n k J /kgK19

20   / / a s t he stea m e xp an ds i s e n t r o p i c a l l y , s 1=s 221   //sg1= sf 2+ x 2∗ s f g 222   x 2 = ( s 1 - s f 2 ) / s f g 2 ;   / / d r y n e s s

f r a c t i o n23   h 2 = h f 2 + x 2 * h f g 2 ;

24

25   E T A r a n k i n e = ( h 1 - h 2 ) / ( h 1 - h f 2 ) ;   / / R a n k i n ee f f i c i e n c y

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26

27   E T A t h e r m a l = I P / ( m / 3 6 0 0 * ( h 1 - h f 2 ) ) ;   //Thermale f f i c i e n c y28   E T A r e l = E T A t h e r m a l / E T A r a n k i n e ;   / / R e l a t i v e

e f f i c i e n c y29

30   printf ( ’ ( i ) The F i n al c o n d i t i o n o f s tea m i s : %1 . 2 f .\n ’ , x 2 ) ;

31   printf ( ’ ( i i ) The R ank ine e f f i c i e n c y i s : %1 . 4 f o r %2. 2 f p e r c e n t .   \n ’ , E T A r a n ki n e , ( E T A r a n k i n e * 1 0 0 ) ) ;

32   printf ( ’ ( i i i ) The R e l a t i v e e f f i c i e n c y i s : %1 . 3 f o r%2 . 1 f p e r c e n t .   \n ’ ,ETArel ,(ETArel*100));

Scilab code Exa 5.9  Example 9

1   clc

2   clear

3   //DATA GIVEN4   T 1 = 4 0 0 + 2 7 3 ;   / / temp . i n K5   T 2 = T 1 ;

6   T 3 = 4 0 + 2 7 3 ;   / / temp . i n K7   T 4 = T 3 ;

8   W = 1 3 0 ;   / / wo rk p r od u ce d i n kJ9

10   E T A t h = ( T 1 - T 3 ) / T 1 ;   / / E n gi n e t h e rm a le f f i c i e n c y

11

12   //ETAth=Work d one / Heat adde d13   H a = W / E T A t h ;   / / Hea t ad ded i n kJ14   H r = H a - W ;   // Heat r e j e c t e d i n kJ

15   / / H ea t r e j e c t e d =T3 ( S 3−S4 )16   S 3 4 = H r / T 3 ;   / / E nt ro py c ha n ge d u r i n gt h e h e a t r e j e c t i o n p r oc e ss

17

18   printf ( ’ ( i ) The E ng in e t he rm al e f f i c i e n c y i s : %1 . 3 f  

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o r %2 . 1 f p e r c e n t .   \n ’ ,ETAth ,(ETAth*100));

19   printf ( ’ ( i i ) The H ea t a dd ed i s : %3 . 0 f kJ .   \n ’ , H a ) ;20   printf ( ’ ( i i i ) The E nt ro py c ha n ge d u r i n g t h e h e a tr e j e c t i o n p r o c es s i s : %1 . 3 f kJ /K.   \n ’ , S 3 4 ) ;

Scilab code Exa 5.10  Example 10

1   clc

2   clear

3   //DATA GIVEN4   p 1 = 1 8 ;   //maximum

p r e s s u r e i n ba r5   T 1 = 4 1 0 + 2 7 3 ;   //maximum

t e mp e r at u r e i n K6   T 2 = T 1 ;

7   R a c = 6 ;   // r a t i o o f  i s e n t r o p i c o r a d i a b a t i c c o mp r es s io n , V4/V1=6

8   R i e = 1 . 5 ;   // r a t i o o f  i s o t h e r m a l e x p a n s i o n , V2 /V1 =1 . 5

9   V 1 = 0 . 1 8 ;   // v olume o f a i r

a t b e g i nn i ng o f i s o t he r m al e xp an si on i n mˆ310   w c = 2 1 0 ;   // no . o f c y c l e s

p er s11

12   / / gamma f o r a i r = 1 .413   g = 1 . 4 ;

14

15   / / f o r i s e n t r o p i c p r o c e s s 4−116   // Als o (T1/T4) =(V4/V1) ˆ( g−1)17   // (V4/V1)=Rac

18   T 4 = T 1 / R a c ^ ( g - 1 ) ;19   T 3 = T 4 ;

20   // p1 ( V1ˆgamma)=p4 (V4ˆgamma)21   //p4=p1 ∗(V1/V4)ˆg22   // where , (V4/V1)=Rac

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23   p 4 = p 1 / ( R a c ^ g ) ;

2425   // f o r i s o t he r ma l p r o c es s 1−226   //p1V1=p2V227   //V1/V2=1/Rie28   p 2 = p 1 * ( 1 / R i e ) ;

29

30   / / f o r i s e n t r o p i c p r o c e s s 2−331   // p2 ( V2ˆgamma)=p3 (V3ˆgamma)32   //V2/V3=V1/V4=1/Rac33   p 3 = p 2 * ( 1 / R a c ) ^ g ;

34

35   / / c h a n g e i n e n t r o p y , DS=S2−S1=mRlog(V2/V1)=p1V1/T1 ∗l o g (V2/V1)

36   D S = p 1 * 1 0 ^ 5 * V 1 / 1 0 ^ 3 / T 1 * log ( R i e ) ;

37

38   / / H ea t s u p p l i e d , Qs=p 1∗V1∗ lo g (V2/V1)39   //Qs=T1(S2−S1 )40   Q s = T 1 * D S ;

41   //Qr=p4∗V4∗ l o g ( V3/V4 ) // h e a tr e j e c t e d i n kJ

42   //Qr=T4(S3−S4 ) , b cs i n c r e a s e i n e nt ro py d ur in g h ea t

a d di t i o n i s e qu al t o d e cr e a s e i n e nt ro py d ur in gh ea t r e j e c t i o n43   Q r = T 4 * D S ;

44

45   E T A = ( Q s - Q r ) / Q s ;   //meant h e r m a l e f f i c i e n c y o f t h e c y c l e

46

47   / / mean e f f e c t i v e p r e s s u r e o f t he c y cl e , Pm = workd on e p e r c y c l e / s t r o k e v ol um e

48   R v 3 1 = R a c * R i e ;   // r a t i o o f  v ol ume s at 3 and 1 , V3/V1=V3/V2∗V2/V1

49   // st r o k e v olume , Vs=V3−V150   Vs=V1 *(Rv31 -1);

51   J = 1 ;

52   P m = ( Q s - Q r ) * 1 0 ^ 3 / 1 0 ^ 5 * J / V s ;

53

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54   P = ( Q s - Q r ) * w c / 6 0 ;   / / p ow er o f  

t he e n g in e i n kW55

56   printf ( ’ ( i ) The P r e s s u r e and T em pe ra tu re a t p o i n t 1ar e : \ n ’ ) ;

57   printf ( ’ p1 : %2 . 0 f b a r . \ n ’ , p 1 ) ;

58   printf ( ’ T1 : %3 . 0 f K.\ n ’ , T 1 ) ;

59   printf ( ’ The P re ss ur e and Te mper at ur e a t p o in t2 a r e :\ n ’ ) ;

60   printf ( ’ p2 : %2 . 0 f b a r . \ n ’ , p 2 ) ;

61   printf ( ’ T2 : %3 . 0 f K.\ n ’ , T 2 ) ;

62   printf ( ’ The P re ss ur e and Te mper at ur e a t p o in t

3 a r e :\ n ’ ) ;63   printf ( ’ p3 : %1 . 2 f b a r . \ n ’ , p 3 ) ;

64   printf ( ’ T3 : %3 . 1 f K.\ n ’ , T 3 ) ;

65   printf ( ’ The P re ss ur e and Te mper at ur e a t p o in t4 a r e :\ n ’ ) ;

66   printf ( ’ p4 : %1 . 2 f b a r . \ n ’ , p 4 ) ;

67   printf ( ’ T4 : %3 . 1 f K.\ n ’ , T 4 ) ;

68   printf ( ’ ( i i ) The Ch ang e i n e n t r o p y d u r i n gi s o t h e r m a l e x p an s i o n i s : %1 . 3 f kJ /K .   \n ’ , D S ) ;

69   printf ( ’ ( i i i ) The Mean t h er m al e f f i c i e n c y o f t h e

c y c l e i s : %1 . 3 f o r %2 . 1 f p e r ce n t .   \n ’, E T A , ( E T A

* 1 0 0 ) ) ;

70   printf ( ’ ( i v ) The Mean e f f e c t i v e p r e s s u r e i s : %1 . 3 f  bar .   \n ’ , P m ) ;

71   printf ( ’ ( v ) The P ower o f t he e ng i ne w o rk in g ont h i s c y c l e i s g i ve n by : %3 . 1 f kW. ’ , P ) ;

72

73   //NOTE:74   / / t h e r e i s s l i g h t v a r i a t i o n i n a ns we r s o f book due

t o r o un di ng o f f o f t h e v a l u es

Scilab code Exa 5.11  Example 11

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1   clc

2   clear3   //DATA GIVEN4   //CASE−15   //( T 1−T2)/T1=1/66   //SO , T1 = 1 . 2 ( T2 ) . . . . . . . . . Eqn ( 1 )7

8   //CASE−29   // T2 REDUCED BY 70 DEG. CELSIUS

10   //{T1−[T2−(70+27 3) ]}/ T1 = 1 / 3 . . . . . . . . . . . . . . Eqn ( 2 )11   //2T1=3T2−102912

13   / /By Eqn ( 1 ) and ( 2 )14   T 2 = ( 7 0 + 2 7 3 ) * 3 / ( 3 - 2 * 1 . 2 ) ;

15   T 1 = 1 . 2 * T 2 ;

16

17   printf ( ’ ( i ) The T em pe ra tu re o f t h e S o ur ce , T1 i s : %4. 0 f K o r %4 . 0 f deg . c e l s i u s .   \n ’ , T 1 , ( T 1 - 2 7 3 ) ) ;

18   printf ( ’ ( i i ) The T em pe ra tu re o f t h e S in k , T2 i s : %4. 0 f K o r %4 . 0 f deg . c e l s i u s .   \n ’ , T 2 , ( T 2 - 2 7 3 ) ) ;

Scilab code Exa 5.12  Example 12

1   clc

2   clear

3   //DATA GIVEN4   T 1 = 1 9 9 0 ;   / / T em pe ra tu re o f t h e

h ea t S ou rc e i n K5   T 2 = 8 5 0 ;   / / T em pe ra tu re o f t h e

h ea t S in k i n K

6   Q s = 3 2 . 5 ;   // h ea t s u p p l i e d i n kJ /mi n7   P = 0 . 4 ;   / / po wer d e v el o p e d by t h e

e n g i n e i n kW8

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9   E T A c a r n o t = ( T 1 - T 2 ) / T 1 ;

10   / / A l s o ETAth=w or k d o ne / H ea t s u p p l i e d11   E T A t h = P / Q s ;

12

13   printf ( ’ The E f f i c i e n c y o f c ar no t c y c l e i s : %1 . 3 f o r%2 . 1 f p e r c e n t .   \n ’ , E T A c a rn o t , ( E T A c a r n o t * 1 0 0 ) ) ;

14   printf ( ’ The Thermal e f f i c i e n c y o f e ng i ne c la im ed byi n v e n t o r i s : %1 . 3 f o r %2 . 1 f p e r ce n t .   \n\n ’ ,ETAth

, ( E T A t h * 1 0 0 ) ) ;

15

16   if ( E T A t h > E T A c a r n o t )

17   printf ( ’ Thus , The c la i m o f t he i n v en t o r i s

p o s s i b l e . ’ ) ;18   else

19   printf ( ’ Thus , The c l ai m o f t he i n v e n t o r i s NOTf e a s i b l e ,   \n a s no e ng i ne can be moree f f i c i e n t t h an t h a t w o r k in g o n c a r n o t c y c l e . ’) ;

Scilab code Exa 5.13  Example 13

1   clc

2   clear

3   //DATA GIVEN4   E T A o t t o = 6 0 ;   // E f f i c i e n c y o f o t t o

c y c l e i n %5   s h r = 1 . 5 ;   / / r a t i o o f s p e c i f i c

h e a t s6

7   //ETAotto=1−1/(r ) ̂ ( sh r −1)

8   r = ( 1 / ( 1 - E T A o t t o / 1 0 0 ) ) ^ ( 1 / ( s h r - 1 ) ) ;   / / c o m p r e s s i o nr a t i o9

10   printf ( ’ The c o m p re s s i on r a t i o i s : %1 . 2 f . ’ , r ) ;

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Scilab code Exa 5.14  Example 14

1   clc

2   clear

3   //DATA GIVEN4   D = 0 . 2 5 ;   // b or e o f t he

e ng i n e i n m5   L = 0 . 3 7 5 ;   // s t r o k e o f t he

e ng i n e i n m6   V c = 0 . 0 0 2 6 3 ;   / / c l e a r a n c e

v ol um e i n mˆ 37   p 1 = 1 ;   // i n i t i a l

p r e s s u r e i n ba r8   T 1 = 5 0 + 2 7 3 ;   // i n i t i a l

t e mp e r at u r e i n K9   p 3 = 2 5 ;   //maximum

p r e s s u r e i n ba r10

11   V s = ( % p i / 4 ) * D ^ 2 * L ;   / / s w e pt v ol um e

12   r = ( V s + V c ) / V c ;   / / c o m p r e s s i o nr a t i o

13

14   / / f o r a i r , gamma = 1. 415   g = 1 . 4 ;

16   // A ir s ta nd ar d e f f i c i e n c y o f o t to c y c l e ETAotto=1−1/( r ) ̂ ( g−1)

17   E T A o t t o = 1 - 1 / ( r ) ^ ( g - 1 ) ;

18

19   // f o r a d i a b a t i c p r oc e ss 1−220   // p1 ( V1ˆgamma)=p2 (V2ˆgamma)21   //p2=p1 ∗(V1/V2)ˆg22   // where , (V1/V2)=r23   p 2 = p 1 * ( r ^ g ) ;   //

p r e s s u r e a t 2 i n ba r

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24   r p = p 3 / p 2 ;   //

p r e s s u r e r a t i o25   P m = p 1 * r * [ ( r ^ ( g - 1 ) - 1 ) * ( r p - 1 ) ] / [ ( g - 1 ) * ( r - 1 ) ] ;   //meane f f e c t i v e p r e s s u r e i n b ar

26

27   printf ( ’ ( i ) The A i r s ta nd ar d e f f i c i e n c y o f o t t oc y c l e i s : %1 . 3 f o r %2 . 1 f p e r ce n t .   \n ’ ,ETAot to ,(

E T A o t t o * 1 0 0 ) ) ;

28   printf ( ’ ( i i ) The Mean e f f e c t i v e p r e s s u r e i s : %1 . 3 f  bar .   \n ’ , P m ) ;

Scilab code Exa 5.15  Example 15

1   clc

2   clear

3   //DATA GIVEN4   T 1 = 3 8 + 2 7 3 ;   // i n i t i a l

t e mp e r at u r e i n K5   T 3 = 1 9 5 0 + 2 7 3 ;   //maximum

t e m p e r a t u r e K

6   r p = 1 5 ;   // p r e s s u r e r a t i o7   / / f o r a i r , gamma = 1. 48   g = 1 . 4 ;

9

10   / / f o r a d i a b a t i c c o mp r es s io n 1−211   // p1 ( V1ˆgamma)=p2 (V2ˆgamma)12   //(V1/V2)=r13   r = ( r p ) ^ ( 1 / g ) ;

14

15   / / T he rm al e f f i c i e n c y ETAth=1−1/( r ) ˆ( g−1)

16   E T A t h = 1 - 1 / ( r ) ^ ( g - 1 ) ;17

18   / / f o r a d i a b a t i c c o mp r es s io n 1−219   // (T2/T1) =(V1/V2) ˆ( g−1)20   //(V1/V2)=r

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21   T 2 = T 1 * r ^ ( g - 1 ) ;

2223   // f o r a d i a b a t i c e xp an si on 3−424   // (T3/T4) =(V4/V3) ˆ( g−1)25   //(V4/V3)=r26   T 4 = T 3 / r ^ ( g - 1 ) ;

27

28   / / h e at s u p p l i e d p e r kg o f a i r , Qs=m∗Cv∗ ( T3−T2 )29   R = 0 . 2 8 7 ;

30   C v = R / ( g - 1 ) ;

31   Q s = C v * ( T 3 - T 2 ) ;

32

33   // h ea t r e j e c t e d p er kg o f a i r , Qr=m∗Cv∗ ( T4−T1 )34   Q r = C v * ( T 4 - T 1 ) ;

35

36   W = Q s - Q r ;   / / wor k d on e p e r kgo f a i r

37

38   printf ( ’ ( i ) The c o mp r es s io n r a t i o i s : %1 . 1 f .\ n ’ , r ) ;

39   printf ( ’ ( i i ) The Thermal e f f i c i e n c y i s : %1 . 3 f o r %2. 1 f p e r c e n t .   \n ’ ,ETAth ,(ETAth*100));

40   printf ( ’ ( i i i ) The Work d o ne i s : %3 . 1 f k J o r %6 . 0 f Nm

. ’, W , ( W * 1 0 0 0 ) ) ;

41

42   //NOTE:43   / / t h e r e i s s l i g h t v a r i a t i o n i n a ns we r s i n t he book

b ec au se o f r o un di ng o f f o f t h e v a l u es

Scilab code Exa 5.16  Example 16

1   clc2   clear

3   //DATA GIVEN4   V 1 = 0 . 4 5 ;   / / v o lu me i n mˆ 35   p 1 = 1 ;   // i n i t i a l pr e s su r e

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i n b ar

6   T 1 = 3 0 + 2 7 3 ;   // i n i t i a lt e mp e r at u r e i n K7   p 2 = 1 1 ;   // p r e s s u r e a t t he

end o f c om pr es si on s t r o k e i n ba r8   Q s = 2 1 0 ;   / / h e a t a d da ed a t

c o n s t a n t vo lu me i n kJ9   w c = 2 1 0 ;   // no . o f w or ki ng

c y c l e s / min10

11   / / f o r a i r , gamma = 1. 412   g = 1 . 4 ;

1314   / / f o r a d i a b a t i c c o mp r es s io n 1−215   // p1 ( V1ˆgamma)=p2 (V2ˆgamma)16   //(V1/V2)=r17   r = ( p 2 / p 1 ) ^ ( 1 / g ) ;

18   // Als o (T2/T1) =(V1/V2) ˆ( g−1)19   //(V1/V2)=r20   T 2 = T 1 * r ^ ( g - 1 ) ;

21

22   / / A p pl yi ng g as l aw s t o p o i n ts 1 and 223

  //p1V1/T1=p2V2/T224   V 2 = T 2 / T 1 * p 1 / p 2 * V 1 ;

25

26   // h ea t s u p pl i e d d ur in g p r o c e s s 2−3 , Qs=mCv( T3−T2 )27   R = 2 8 7 ;

28   m = p 1 * 1 0 ^ 5 * V 1 / R / T 1 ;

29   C v = R / 1 0 0 0 / ( g - 1 ) ;

30   T 3 = Q s / m / C v + T 2 ;

31

32   // f o r c o n st a n t volume p r o c e s s 2−333   //p3/T3=p2/T2

34   p 3 = p 2 / T 2 * T 3 ;35   V 3 = V 2 ;

36

37   // f o r a d i a b a t i c e xp an si on 3−438   // p3 ( V3ˆgamma)=p4 (V4ˆgamma)

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39   //(V4/V3)=r

40   p 4 = p 3 * ( 1 / r ) ^ ( g ) ;41   // Als o T3/T4) =(V4/V3) ˆ( g−1)42   //(V4/V3)=r43   T 4 = T 3 / r ^ ( g - 1 ) ;

44   V 4 = V 1 ;

45

46   // pe r c e n t a ge c l e a r a nc e , pc=Vc /Vs=V2/( V1−V2 )47   p c = V 2 / ( V 1 - V 2 ) * 1 0 0 ;

48

49   / / h e a t r e j e c t e d p e r c y c l e , Qr=Cv∗( T4−T1 )50   Q r = m * C v * ( T 4 - T 1 ) ;

5152   // A i r s t an d ar d e f f i c i e n c y o f o t t o c y c l e ETAotto=(Qs−

Qr)/Qs53   E T A o t t o = ( Q s - Q r ) / Q s ;

54   / / A l t e r n a t i v e l y55   //ETAotto=1−1/( r ) ˆ( g−1)56   E T A o t t o = 1 - 1 / ( r ) ^ ( g - 1 ) ;

57

58   / / m ean e f f e c t i v e p r e s s u r e , Pm=W/ Vs59   W = Q s - Q r ;   / / wor k d on e p e r kg

o f a i r60   V s = V 1 - V 2 ;

61   P m = W * 1 0 ^ 3 / 1 0 ^ 5 / V s ;

62

63   / / p ow er d e v el o p ed , P=wo rk d on e p e r c y c l e ∗no . o f  c y c l e s p e r s

64   P = W * ( w c / 6 0 ) ;

65

66   printf ( ’ ( i ) The P r e s s u r e , T e mp e ra t ur e a nd V ol um esa t s a l i e n t p o i n t s i n t h e c y c l e a re :\ n ’ ) ;

67   printf ( ’ At p o i n t 1 a r e : \ n ’ ) ;

68   printf ( ’ p1 : %1 . 1 f b a r . \ n ’ , p 1 ) ;69   printf ( ’ V1 : %1 . 2 f mˆ 3 .\ n ’ , V 1 ) ;

70   printf ( ’ T1 : %3 . 0 f K.\ n ’ , T 1 ) ;

71   printf ( ’ At p o i n t 2 a r e : \ n ’ ) ;

72   printf ( ’ p2 : %2 . 2 f b a r . \ n ’ , p 2 ) ;

72

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73   printf ( ’ V2 : %1 . 3 f mˆ 3 .\ n ’ , V 2 ) ;

74   printf ( ’ T2 : %3 . 0 f K.\ n ’ , T 2 ) ;75   printf ( ’ At p o i n t 3 a r e : \ n ’ ) ;

76   printf ( ’ p3 : %2 . 2 f b a r . \ n ’ , p 3 ) ;

77   printf ( ’ V3 : %1 . 3 f mˆ 3 .\ n ’ , V 3 ) ;

78   printf ( ’ T3 : %4 . 0 f K.\ n ’ , T 3 ) ;

79   printf ( ’ At p o i n t 4 a r e : \ n ’ ) ;

80   printf ( ’ p4 : %1 . 2 f b a r . \ n ’ , p 4 ) ;

81   printf ( ’ V4 : %1 . 2 f mˆ 3 .\ n ’ , V 4 ) ;

82   printf ( ’ T4 : %3 . 1 f K.\ n ’ , T 4 ) ;

83   printf ( ’ ( i i ) The P e r ce n t ag e c l e a r a n c e i s : %2 . 2 f  p e r c e n t .   \n ’ , p c ) ;

84   printf ( ’ ( i i i ) The A ir s ta nd ar d e f f i c i e n c y o f t hec y c l e i s : %1 . 3 f o r %2 . 1 f p e r ce n t .   \n ’ ,ETAot to ,(

E T A o t t o * 1 0 0 ) ) ;

85   printf ( ’ ( i v ) The Mean e f f e c t i v e p r e s s u r e i s : %1 . 3 f  bar .   \n ’ , P m ) ;

86   printf ( ’ ( v ) The Power d e v el o p e d i s : %3 . 1 f kW. ’ , P ) ;

87

88   //NOTE:89   / / t h e r e i s s l i g h t v a r i a t i o n i n a ns we r s i n t he book

b ec au se o f r o un di ng o f f o f t h e v a l u es

Scilab code Exa 5.17  Example 17

1   clc

2   clear

3   //DATA GIVEN4   r = 1 5 ;   / / c o m p re s s i on r a t i o5   //V3−V2=a/100∗Vs . . . . . . . . . . . . Vs=s t r o k e volume=V1−V2

6   //V3=1.84V27   c = 6 ;   // h ea t a d d i t i o n t a k esp l a c e a t ’ a ’ p e r c e nt o f s t r o k e

8   / / f o r a i r , gamma = 1. 49   g = 1 . 4 ;

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10

11   // A ir s ta nd ar d e f f i c i e n c y o f d i e s e l c y c l e E T A d i e s e l=1 −[1/(r ) ̂ ( g−1) ] [ ( rh o ˆg −1)/ ( rho −1) ]12   // r h o=c u t o f f r a t i o =V3 /V213   r h o = c / 1 0 0 * ( r - 1 ) + 1 ;

14   E T A d i e s e l = 1 - [ 1 / g / ( r ) ^ ( g - 1 ) ] * [ ( r h o ^ g - 1 ) / ( r h o - 1 ) ] ;

15

16   printf ( ’ The A i r s t an da rd e f f i c i e n c y o f d i e s e l c y c l ei s : %1 . 3 f o r %2 . 1 f p e r c e n t .   \n ’ ,ETAdiesel ,(

E T A d i e s e l * 1 0 0 ) ) ;

Scilab code Exa 5.18  Example 18

1   clc

2   clear

3   //DATA GIVEN4   L = 0 . 2 5 ;   // s t r o k e o f t he

e ng i n e i n m5   D = 0 . 1 5 ;   / / d i a m e t e r o f  

c y l i n d e r i n m

6   V 2 = 0 . 0 0 0 4 ;   / / c l e a r a n c ev ol um e i n mˆ 3

7   V s = ( % p i / 4 ) * D ^ 2 * L ;   / / s w ep t v ol um e i nmˆ3

8   V t = V s + V 2 ;   // t o t a l c y l i n d e rv ol um e i n mˆ 3

9   c = 5 ;   // f u e l i n j e c t i o nt ak es p l a c e a t ’ c ’ p er ce nt o f s t r o k e

10   V 3 = V 2 + c / 1 0 0 * V s ;   / / vo lu me a t p o i n to f c ut−o f f i n mˆ3

11   r h o = V 3 / V 2 ;   / / c u t−o f f r a t i o12   r = ( V s + V 2 ) / V 2 ;   / / c o m p r e s s i o nr a t i o

13

14   / / f o r a i r , gamma = 1. 4

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15   g = 1 . 4 ;

1617   // A ir s ta nd ar d e f f i c i e n c y o f d i e s e l c y c l e E T A d i e s e l

=1 −[1/(r ) ̂ ( g−1) ] [ ( rh o ˆg −1)/ ( rho −1) ]18   E T A d i e s e l = 1 - [ 1 / g / ( r ) ^ ( g - 1 ) ] * [ ( r h o ^ g - 1 ) / ( r h o - 1 ) ] ;

19

20   printf ( ’ The E f f i c i e n c y o f d i e s e l e ng in e i s : %1 . 3 f  o r %2 . 1 f p e r c e n t .   \n ’ , E T A d i es e l , ( E T A d i e s e l * 1 0 0 ) ) ;

Scilab code Exa 5.19  Example 19

1   clc

2   clear

3   //DATA GIVEN4   r = 1 4 ;   / / c o m p re s s i on r a t i o5   / / f u e l c ut−o f f i s d el ay ed from 5−8%6   / / f o r a i r , gamma = 1. 47   g = 1 . 4 ;

8

9   // when f u e l i s cut−o f f a t 5%

10   c 1 = 5 ;11   r h o 1 = c 1 / 1 0 0 * ( r - 1 ) + 1 ;

12   // E f f i c i e n c y o f d i e s e l e ng i ne E TA d ie se l =1−[1/(r ) ̂ ( g−1) ] [ ( rh o ˆg−1)/ ( rho −1) ]

13   E T A d i e s e l 1 = 1 - [ 1 / g / ( r ) ^ ( g - 1 ) ] * [ ( r h o 1 ^ g - 1 ) / ( r h o1 - 1 ) ] ;

14

15   // when f u e l i s cut−o f f a t 8%16   c 2 = 8 ;

17   r h o 2 = c 2 / 1 0 0 * ( r - 1 ) + 1 ;

18   // E f f i c i e n c y o f d i e s e l e ng i ne E TA d ie se l =1−[1/(r ) ̂ ( g

−1) ] [ ( rh o ˆg−1)/ ( rho −1) ]19   E T A d i e s e l 2 = 1 - [ 1 / g / ( r ) ^ ( g - 1 ) ] * [ ( r h o 2 ^ g - 1 ) / ( r h o2 - 1 ) ] ;

20

21   E T A l o s s = ( E T A d i e s e l1 - E T A d i e s e l 2 ) * 1 0 0 ;

22

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23   printf ( ’ The P er ce nt ag e l o s s i n e f f i c i e n c y due t o

d el ay i n f u e l cut−o f f i s : %1 . 1 f p e r ce n t .   \n ’ ,E T A l o s s ) ;

Scilab code Exa 5.20  Example 20

1   clc

2   clear

3   //DATA GIVEN

4   P m = 7 . 5 ;   // mean e f f e c t i v ep r e s s u r e i n ba r5   r = 1 2 . 5 ;   / / c o m p re s s i on r a t i o6   p 1 = 1 ;   / / i n i t i a l p r e s s u r e i n

b ar7

8   / / f o r a i r , gamma = 1. 49   g = 1 . 4 ;

10

11   / / mean e f f e c t i v e p r e s s u r e , Pm=p1∗ r ˆ g ∗ [ g ∗( r h o −1)−rˆ( 1−g ) ∗ ( r ho ˆg−1) ] / [ ( g−1) ∗ ( r −1) ]

12   / / we g e t , 0 . 3 4 6 ( r h o ) ̂ 1 . 4 −1. 4( rho ) +2.0 413   / /By t r i a l a nd e r r o r m ethod , we g e t14   r h o = 2 . 2 4 ;

15

16   c o = ( r h o - 1 ) / ( r - 1 ) * 1 0 0 ;   //% cut−o f f 17

18   printf ( ’ The P e r ce n t ag e c ut−o f f o f t h e c y c l e i s : %2. 2 f p e r c e n t .   \n ’ , c o ) ;

Scilab code Exa 5.21  Example 21

1   clc

2   clear

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31

32   / / c u t−o f f r a t i o , c =( rho −1 ) / ( r −1)33   r h o = c / 1 0 0 * ( r - 1 ) + 1 ;

34   V 3 = r h o * V 2 ;

35   // a l t e r n a t i v e l y36   V 3 = c / 1 0 0 * V s + V c ;

37

38   / / f o r c o ns t an t p r e s su r e p r o c es s 2−339   //V3/T3=V2/T240   T 3 = T 2 / V 2 * V 3 ;

41

42   / / f o r i s e n t r o p i c p r o c e s s 3−4

43   // p3 ( V3ˆgamma)=p4 (V4ˆgamma)44   // ( V4/V)=V4/V2∗V2/V3=V1/V2∗V2/V3=r/rho45   p 4 = p 3 * ( ( r h o / r ) ^ g ) ;

46   // Als o (T4/T3) =(V3/V4) ˆ( g−1)47   // ( V4/V)=V4/V2∗V2/V3=V1/V2∗V2/V3=r/rho48   T 4 = T 3 * ( ( r h o / r ) ^ ( g - 1 ) ) ;

49   V 4 = V 1 ;

50

51   // A ir s ta nd ar d e f f i c i e n c y o f d i e s e l c y c l e E T A d i e s e l=1 −[1/(r ) ̂ ( g−1) ] [ ( rh o ˆg −1)/ ( rho −1) ]

52   E T A d i e s e l = 1 - [ 1 / g / ( r ) ^ ( g - 1 ) ] * [ ( r h o ^ g - 1 ) / ( r h o - 1 ) ] ;

53

54   / / mean e f f e c t i v e p r e s s u r e , Pm=p1∗ r ˆ g ∗ [ g ∗( r h o −1)−rˆ( 1−g ) ∗ ( r ho ˆg−1) ] / [ ( g−1) ∗ ( r −1) ] ;

55   P m = p 1 * r ^ g * [ g * ( r h o - 1 ) - r ^ ( 1 - g ) * ( r h o ^ g - 1 ) ] / [ ( g - 1 ) * ( r - 1 )

];

56

57   P = P m * 1 0 ^ 5 * V s / 1 0 ^ 3 * ( w c / 6 0 ) ;   / / Po we r o f  t he e n g in e i n kW

58

59   printf ( ’ ( i ) The P r e s s u r e , T e mp e ra t ur e a nd V ol um es

a t s a l i e n t p o i n t s i n t h e c y c l e a re :\ n ’ ) ;60   printf ( ’ At p o i n t 1 a r e : \ n ’ ) ;

61   printf ( ’ p1 : %1 . 1 f b a r . \ n ’ , p 1 ) ;

62   printf ( ’ V1 : %1 . 4 f mˆ 3 .\ n ’ , V 1 ) ;

63   printf ( ’ T1 : %3 . 0 f K.\ n ’ , T 1 ) ;

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64   printf ( ’ At p o i n t 2 a r e : \ n ’ ) ;

65   printf ( ’ p2 : %2 . 2 f b a r . \ n ’ , p 2 ) ;66   printf ( ’ V2 : %1 . 7 f mˆ 3 .\ n ’ , V 2 ) ;

67   printf ( ’ T2 : %3 . 1 f K.\ n ’ , T 2 ) ;

68   printf ( ’ At p o i n t 3 a r e : \ n ’ ) ;

69   printf ( ’ p3 : %2 . 2 f b a r . \ n ’ , p 3 ) ;

70   printf ( ’ V3 : %1 . 6 f mˆ 3 .\ n ’ , V 3 ) ;

71   printf ( ’ T3 : %4 . 1 f K.\ n ’ , T 3 ) ;

72   printf ( ’ At p o i n t 4 a r e : \ n ’ ) ;

73   printf ( ’ p4 : %1 . 3 f b a r . \ n ’ , p 4 ) ;

74   printf ( ’ V4 : %1 . 4 f mˆ 3 .\ n ’ , V 4 ) ;

75   printf ( ’ T4 : %3 . 2 f K.\ n ’ , T 4 ) ;

76   printf ( ’ ( i i ) The T h e o r i t i c a l a i r s ta nd ar de f f i c i e n c y o f d i e s e l c y c l e i s : %1 . 3 f o r %2 . 1 f  p e r c e n t .   \n ’ , E T A d i es e l , ( E T A d i e s e l * 1 0 0 ) ) ;

77   printf ( ’ ( i i i ) The Mean e f f e c t i v e p r e s s u r e i s : %1 . 3 f  bar .   \n ’ , P m ) ;

78   printf ( ’ ( i v ) The Po wer d e v e l o p e d i s : %2 . 2 f kW . ’ , P ) ;

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Chapter 6

Steam Boilers

Scilab code Exa 6.1  Example 1

1   clc

2   clear

3   //DATA GIVEN4   L C V = 4 4 7 0 0 ;   //LCV o f f u e l i n kJ5   a f r n = 2 0 ;   // a i r p a rt s =20 i n a i r f u e l

m i x t u r e

6   a f r d = 1 ;   // f u e l p a r t s =1 i n a i r f u e lm i x t u r e

7   C p g = 1 . 0 8 ;   / / a vg s p e c i f i c h e a t i n kJ /kgK

8   T 1 = 3 8 + 2 7 3 ;   // b o i l e r room temp . i n K9

10   / / h e at o f c om bu st io n=h e at o f g a s e s11   // 1∗44700=Mg∗Cpg ∗ ( T2−T1 )12   T 2 = a f r d * L C V / ( a f r n + a f r d ) / C p g + T 1 ;

13

14   printf ( ’ The Maximum temp . T2 a t t a i n e d i n t h ef ur na c e o f t h e b o i l e r i s : \ n %5 . 0 f K el v in ’ , T 2 ) ;

15   printf ( ’ o r %5 . 0 f d e gr e e c e l s i u s . \ n ’  , ( T2 - 2 7 3 ) ) ;

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Scilab code Exa 6.2  Example 2

1   clc

2   clear

3   //DATA GIVEN4   M s = 5 . 4 ;   // mass o f s team u se d i n kg /

kWh5   p = 5 0 ;   // p r e s s u r e o f stea m i n b ar6   T s u p = 3 5 0 ;   / / temp . o f s te am i n d eg

c e l s i u s7   e t a = 8 2 ;   // b o i l e r e f f i c i e n c y i n %8   T f w = 1 5 0 ;   / / f e e d w at er temp . i n d eg c e l

; s i u s9   C = 2 8 1 0 0 ;   / / c a l o r i f i c v a l u e o f c o a l i n

kJ10   r a t e = 5 0 0 ;   // c o s t o f c o a l / t on ne i n Rs11

12   // b o i l e r e f f i c i e n c y i s g i v e n by , e ta=Ms∗( hsup−hf 1 ) /(Mf ∗C)

13   / / f rom stea m t a bl e , a t 45 b ar and 35 0 deg c e l s i u s ,h su p = 3 0 6 8. 4 k J / kg

14   h = 3 0 6 8 . 4 ;   / / e n t h a l p y a t45 b a r and 350 deg c e l s i u s

15   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;   // h f 1 a t 1 50deg c e l s i u s i n k J /kg

16

17   // s ub s . t he se i n eq . o f b o i l e r e f f i c i e n c y18   M f = M s * ( h - h f 1 ) / ( ( e t a / 1 0 0 ) * C ) ;   // mass o f c o a l

r e q u i r e d i n kg /kWh19   c o s t = ( M f / 1 0 0 0 ) * r a t e * 1 0 0 ;   // c o s t o f c o a l

i n pa i s a /kWh20

21   printf ( ’ ( i ) The mass o f c o a l r e q ui r e d i s : %5 . 3 f kg/kWh.   \n ’ , M f ) ;

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22   printf ( ’ ( i i ) The T ot al c o s t o f f u e l ( c o a l ) i s : %2 . 1

f pa i s a /kWh.   \n ’ , c o s t ) ;23

24   //NOTE: in te xt book25   / / i n q u e s t i on p r e s s ur e i s g i ve n a s =50 ba r26   / / but from steam t a b l e e nt ha l p y i s f o un d a t 45 b ar

Scilab code Exa 6.3  Example 3

1   clc2   clear

3   //DATA GIVEN4   M c = 1 2 5 0 ;   // q u an t it y o f c o a l i n kg

co ns um ed i n 2 4 h o u r s5   M w = 1 3 0 0 0 ;   // m ass o f w at er

e va p or a te d i n kg6   M E P s = 7 ;   // mean e f f e c t i v e p r e s s ur e

o f steam i n b ar7   T f w = 4 0 ;   / / f e e d w a te r temp . i n d eg

c e l s i u s

8   h = 2 5 7 0 . 7 ;   // e n th a lp y o f s tea m a t 7b ar i n kJ / kg

9   C = 3 0 0 0 0 ;   / / c a l o r i f i c v a l u e o f c o a li n kJ / kg

10

11   M a = M w / M c ;   // mass o f w at er a c t u a l l ye va po ra t e d p er kg o f f u e l

12   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;

13   h f g = 2 2 5 7 ;   / / i n kJ / k g14   M e = M a * ( h - h f 1 ) / h f g ;   / / i n k g

15   e t a = M a * ( h - h f 1 ) / C ;   // b o i l e r e f f i c i e n c y16

17   printf ( ’ ( i ) The e q ui v a l e n t e v a p o r a t i o n p er kg o f  c o a l , Me i s : %5 . 3 f kg .   \n ’ , M e ) ;

18   printf ( ’ ( i i ) The e f f i c i e n c y o f b o i l e r , e t a i s : %1

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. 3 f o r %2 . 1 f p e r ce n t . ’ , e t a , e t a * 1 0 0 ) ;

Scilab code Exa 6.4  Example 4

1   clc

2   clear

3   //DATA GIVEN4   p = 1 2 ;   / /mean s te am p r e s s u r e i n

b ar

5   M s = 4 0 0 0 0 ;   / / mass o f s tea m g e n e r a t edi n kg6   x = 0 . 8 5 ;   // mean d r yn e s s f r a c t i o n7   T f w = 3 0 ;   / /mean f e e d wa te r temp . i n

deg c e l s i u s8   M c = 4 0 0 0 ;   // mass o f c o a l u se d i n kg9   C = 3 3 4 0 0 ;   / / c a l o r i f i c v a l u e o f c o a l

i n kJ / kg10

11   // f rom stea m t a bl e , c o r r es p o n d i ng t o 12 bar ,12   h f = 7 9 8 . 4 ;   / / i n k J / kg

13   h f g = 1 9 8 4 . 3 ;   / / i n k J / kh14   h = h f + x * h f g ;   / / i n k j / k g15   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;   // h ea t o f f e e d w a te r i n kJ /

kg16

17   F e = ( h - h f 1 ) / 2 2 5 7 ;   // f a c t o r o f e q u i v al e n te v a p o r a t i o n , Fe

18   M a = M s / M c ;   // p er kg o f f u e l19   M e = M a * ( h - h f 1 ) / 2 2 5 7 ;   // ( kg o f s tea m ) / ( kg o f f u e l

)

20   e t a = M a * ( h - h f 1 ) / C ;   // e f f i c i e n c y o f b o i l e r21

22   printf ( ’ ( i ) The F ac to r o f e q u i v a l e n t t em er at ur e , Fei s : %5 . 3 f   \n ’ , F e ) ;

23   printf ( ’ ( i i ) The E q ui v a le n t e v a p or a t i on from and

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a t 100 deg c e l s i u s , Me i s : %5 . 2 f ( kg o f steam ) / (

kg o f c o a l ) . \ n ’ , M e ) ;24   printf ( ’ ( i i i ) The E f f i c i e n c y o f b o i l e r i s : %5 . 4 f ’ ,

e t a ) ;

25   printf ( ’ o r %5 . 2 f p e r c e n t .   \n ’ , e t a * 1 0 0 ) ;

Scilab code Exa 6.5  Example 5

1   clc

2   clear3   //DATA GIVEN4   M = 1 8 0 0 0 ;   // mass o f stea m g e n er a t ed i n

k g / h r5   p = 1 2 . 5 ;   // s tea m p r e s s u r e i n b ar6   x = 0 . 9 7 ;   // q u a l i t y o f stea m7   T f w = 1 0 5 ;   // f e e d w at er temp . i n deg

c e l s i u s8   M f = 2 0 4 0 ;   // r a t e o f c o a l f i r i n g i n kg /

hr9   C = 2 7 4 0 0 ;   / / h i g h r e r c a l o r i f i c v a l u e (

HCV) o f c o a l i n kJ / kg10

11   // f rom stea m t a bl e , c o r r es p o n d i ng t o 1 2 . 5 bar ,12   h f = 8 0 6 . 7 ;   / / i n k J / kg13   h f g = 1 9 7 7 . 4 ;   / / i n k J / kg14   h = h f + x * h f g ;   / / i n k J / kg15   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;   // h ea t of f e e d w a te r i n kJ /

kg16

17   // h ea t r a t e o f t he b o i l e r = h ea t s u pp l i e d p er hour

18   h e a t r a t e = M * ( h - h f 1 )   // h ea t r a te o f b o i l e r19   M a = M / M f ;   // i n kg p er kg o f f u e l20   M e = M a * ( h - h f 1 ) / 2 2 5 7 ;   // ( kg o f s team ) / ( kg o f f u e l )21   e t a = M a * ( h - h f 1 ) / C ;   // t he rm al e f f i c i e n c y22

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23   printf ( ’ ( i ) The Heat r a t e o f b o i l e r i s : %1 . 4 e kJ /h .

\n ’ , h e a t r a t e ) ;24   printf ( ’ ( i i ) The E q u i v a le n t e v a p or a t i on , Me i s : %5. 3 f ( k g o f s team ) / ( kg o f f u e l ) .   \n ’ , M e ) ;

25   printf ( ’ ( i i i ) The Therma l e f f i c i e n c y i s : %5 . 4 f ’ ,eta

) ;

26   printf ( ’ o r %5 . 2 f p e r c e n t .   \n ’ , e t a * 1 0 0 ) ;

Scilab code Exa 6.6  Example 6

1   clc

2   clear

3   //DATA GIVEN4   M w = 5 9 4 0 ;   / / mass o f w at er e v a po r a te d kg / h r5   M c = 6 7 5 ;   // mass o f c o a l b ur nt i n kg / hr6   C = 3 1 6 0 0 ;   // lo we r c a l o r i f i c va lu e (LCV) of  

c o a l i n kJ /kg7   p 1 = 1 4 ;   // p r e s s ur e o f steam a t b o i l e r

s to p v al ve i n ba r8   T e 1 = 3 2 ;   // temp . o f f e e d w at er e n t e r i n g

e co no mi se r i n deg c e l s i u s9   T e 2 = 1 1 5 ;   // temp . o f f e e d w at er l e a v i n g

e co no mi se r i n deg c e l s i u s10   x = 0 . 9 6 ;   // d r yn e s s f r a c t i o n o f stea m

e n t e r i n g s u p e r h e a t e r11   T s u p = 2 6 0 ;   / /temp . o f s te am l e a v i n g

s u pe r h e a t er i n deg c e l s i u s12   C p = 2 . 3   / / s p e c i f i c h e a t o f s u p e r h e a t e d

steam13

14   h f 1 = 4 . 1 8 * ( T e 2 - T e 1 ) ;   // hea tu t i l i s e d by 1 kg o f f e e d w a t e r i n e co no mi se r15   // f rom stea m t a bl e , c o r r es p o n d i ng t o 14 bar ,16   T s = 1 9 5 ;

17   h f = 8 3 0 . 1 ;

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18   h f g = 1 9 5 7 . 7 ;

19   h b o i l e r = ( h f + x * h f g ) - h f 1 ;   // hea tu t i l i s e d by 1 kg o f f e ed w a t e r i n b o i l e r20   h s u p e r h e a t e r = ( 1 - x ) * h f g + C p * ( T s u p - T s ) ;   // hea t

u t i l i s e d by 1 kg o f f ee d w a t e r i n s u p e r he at e r21   M a = M w / M c ;   / / i n kg p e r

kg o f f u e l22   P e = h f 1 / C * M a * 1 0 0 ;   / /% o f h e at

u t i l i s e d i n e co no mi se r23   P b = h b o i l e r / C * M a * 1 0 0 ;   / /% o f h e at

u t i l i s e d i n b o i l e r24   P s = h s u p e r h e a t e r / C * M a * 1 0 0 ;   / /% o f h e at

u t i l i s e d i n s up e r he a t e r25   h t o t a l = h f 1 + h b o i l e r + h s u p e r h e a t e r ;   // t o t a l h ea t

a bs or be d i n kg o f w at er26   e t a = M a * h t o t a l / C ;   / / o v e r a l l

e f f i c i e n c y o f b o i l e r p la nt27

28   printf ( ’ ( i ) The P er ce nt ag e o f h ea t u t i l i s e d i nE c on o mi s er i s : %5 . 2 f p e r c e n t . \ n ’ , P e ) ;

29   printf ( ’ The P e r c e n t a g e of he a t u t i l i s e d i nB o i l e r i s : %5 . 2 f p e r ce n t .\ n ’ , P b ) ;

30   printf ( ’ The P e r c e n t a g e of he a t u t i l i s e d i nS u p e r he a t e r i s : %5 . 2 f p e r c e n t .\ n ’ , P s ) ;

31   printf ( ’ ( i i ) The O v e r a l l E f f i c i e n c y o f b o i l e r p l a nti s : %5 . 4 f ’ , e t a ) ;

32   printf ( ’ o r %5 . 2 f p e r c e n t .   \n ’ , e t a * 1 0 0 ) ;

Scilab code Exa 6.7  Example 7

1   clc2   clear

3   //DATA GIVEN4   C = 2 9 9 1 5 ;   / / c a l o r i f i c v a l u e o f c o a l i n kJ /

kg

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5   M w = 9 . 1 ;   // mass o f f e ed w a te r p er kg o f  

dr y c o a l i n kg6   M e = 9 . 6 ;   / / e q u i v a l e n t e v a p o r a t i o n f ra omand a t 100 deg c e l s i u s p e r kg o f dry c o a l i n k g

7   T e = 1 2 ;   // temp . o f f e e d w at er t oe co no mi se r i n deg c e l s i u s

8   T b = 1 0 5 ;   // temp . o f f e ed w at er t o b o i l e ri n d eg c e l s i u s

9   T a = 1 3 ;   / /temp . o f a i r10   T f g = 3 7 0 ;   // temp . o f f l u e g a s es e n t e r i n g

e c o n o m i s e r11   M f g = 1 8 . 2 ;   // mass o f f l u e g a s e s e n t e r i n g

e co no mi se r p er kg o f c o a l12   C p = 1 . 0 4 6 ;   / / mean s p e c i f i c h e a t o f f l u e

g a s e s13

14   h b = M e * 2 2 5 7 ;   // h ea t s u p p l i e d f o r s tea mg e n e r a t i o n i n kJ

15   E T A b = h b / C ;   // b o i l e r e f f i c i e n c y16   h f l u e = M f g * C p * ( T f g - T a ) ;   // h ea t i n t h e f l u e g as e

p er kg o f dr y c o a l e n t e r i n g e co no mi se r17   h e = M w * 4 . 1 8 4 * ( T b - T e ) ;   // h ea t u t i l i s e d i n

e c o n o m i s e r18   E T A e = h e / h f l u e ;   // e co n om i se r e f f i c i e n c y19   h t o t a l = h b + h e ;   // t o t a l h ea t a bs o rb ed i n

kg o f w a te r20   E T A = h t o t a l / C ;   // b o i l e r p la nt e f f i c i e n c y21

22   printf ( ’ ( i ) The B o i l e r e f f i c i e n c y i s : %5 . 3 f ’ , E T A b )

;

23   printf ( ’ o r %2 . 1 f p e r c e n t .   \n ’ , E T A b * 1 0 0 ) ;

24   printf ( ’ ( i i ) The E co no mi se r e f f i c i e n c y i s : %5 . 3 f ’ ,

E T A e ) ;

25   printf ( ’ o r %2 . 2 f p e r c e n t .   \n ’ , E T A e * 1 0 0 ) ;26   printf ( ’ ( i i i ) The O v er a l l E f f i c i e n c y o f b o i l e r p l an t

i s : %5 . 3 f ’ , E T A ) ;

27   printf ( ’ o r %2 . 1 f p e r c e n t .   \n ’ , E T A * 1 0 0 ) ;

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Scilab code Exa 6.8  Example 8

1   clc

2   clear

3   //DATA GIVEN4   M s = 2 0 0 0 ;   // r a t e o f s tea m p r o du c ti o n i n kg

/ hr5   x = 1 ;   // q u a l i t y o f s team6   p = 1 0 ;   // steam p r e s s ur e i n b ar7   T f w = 1 1 0 ;   // f e e d w at er temp . i n d eg

c e l s i u s8   M f = 2 2 5 ;   // r a t e o f c o a l f i r i n g i n kg / h r9   C = 3 0 1 0 0 ;   / / c a l o r i f i c v a l u e o f c o a l i n kJ /

kg10   P u c = 1 0 ;   / /% o f u nb ur nt c o a l11

12   // f rom stea m t a bl e , c o r r es p o n d i ng t o 10 bar ,13   h = 2 7 7 6 . 2 ;   / / i n k J / kg14   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;   // h ea t c o n ta i n ed i n 1 kg

o f f e e d w a t e r b e f o r e e n t e r i n g b o i l e r i n k J /kg15   h t o t a l = h - h f 1   // t o t a l h ea t g i ve n t o

p r o du ce 1 kg o f steam i n b o i l e r i n kJ /kg16   M c = M f * ( 1 0 0 - P u c ) / 1 0 0 ;   // mass o f c o a l a c t u a l l y

b ur n t i n kg17   M a = M s / M c ;   / / ( k g o f s te am ) / ( k g o f  

f u e l )18   E T A b = M a * ( h - h f 1 ) / C ;   // t he rm al e f f i c i e n c y o f  

b o i l e r19   E T A c = ( M s / M f ) * ( h - h f 1 ) / C ;   // t he rm al e f f i c i e n c y o f  

b o i l e r and g r a t e co mb ined20

21   printf ( ’ ( i ) The Thermal e f f i c i e n c y o f t h e b o i l e r i s: %5 . 3 f ’ , E T A b ) ;

22   printf ( ’ o r %5 . 2 f p e r c e n t .   \n ’ , E T A b * 1 0 0 ) ;

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23   printf ( ’ ( i i ) The Thermal e f f i c i e n c y o f t he b o i l e r

and g r a t e co mb in ed i s : %5 . 3 f ’ , E T A c ) ;24   printf ( ’ o r %5 . 2 f p e r c e n t .   \n ’ , E T A c * 1 0 0 ) ;

Scilab code Exa 6.9  Example 9

1   clc

2   clear

3   //DATA GIVEN

4   M a = 7 . 5 ;   // mass o f s tea m g e n er a t ed p er kgo f c o a l5   p = 1 1 ;   // steam p r e s s ur e i n b ar6   T f w = 7 0 ;   / /temp . o f f e e d w at er temp . i n

deg c e l s i u s7   e t a = 7 5 ;   // e f f i c i e n c y o f b o i l e r i n %8   F e = 1 . 1 5 ;   // f a c t o r o f e v ap o ra t i o n9   C p s = 2 . 3 ;   / / s p e c i f i c h e a t o f s te a m i n k J /

kgK10

11   // f rom stea m t a bl e , c o r r es p o n d i ng t o 11 bar ,

12   h f = 7 8 1 . 4 ;   / / i n k J / kg13   h f g = 1 9 9 8 . 5 ;   / / i n k J / kg14   T s = 1 8 4 . 1 + 2 7 3 ;   / / i n K15   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;

16

17   / / F a c t o r o f e v a p o r a t i o n , Fe =[{ h f+hf g+Cps∗(Tsup−Ts )}−h f 1 ] / 2 2 5 7

18   T s u p = [ F e * 2 2 5 7 + h f 1 - h f - h f g ] / C p s + T s ;   / / Tsup i n K19   x = ( T s u p - T s ) ;   / / d e g r e e o f  

s up er he at i n deg . c e l s i u s

2021   // B o i l e r e f f i c i e n c y e t a=Ma∗ ( h−hf 1 ) /C ;22   h = [ h f + h f g + C p s * ( T s u p - T s ) ] ;

23   C = M a * ( h - h f 1 ) / ( e t a / 1 0 0 ) ;   // c a l o r i f i cv al ue o f c o al i n k J/ kg

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24   M e = M a * ( h - h f 1 ) / 2 2 5 7 ;   //

E q ui v al e nt e v a po r a t io n im kg25

26   printf ( ’ ( i ) The T em pe ra tu re o f s te am g e n e r a t i o n ,Tsup i s : %5 . 1 f K\n ’ , T s u p ) ;

27   printf ( ’ The De g r e e o f s u p er h ea t i s : %5 . 1 f d egc e l s i u s .\ n ’ , x ) ;

28   printf ( ’ ( i i ) The c a l o r i f i c v a l u e o f c o a l , C i s : %5. 0 f k J / kg .   \n ’ , C ) ;

29   printf ( ’ ( i i i ) The E q u i v a l e n t e v a p o r a t i o n , Me i s : %5. 3 f k g .   \n ’ , M e ) ;

Scilab code Exa 6.10  Example 10

1   clc

2   clear

3   //DATA GIVEN4   p = 1 3 ;   // s team p r e s s ur e i n b ar5   d s = 7 7 ;   // d e gr e e o f s u p er h ea t i n

deg . c e l s i u s

6   T f w = 8 5 ;   // temp . o f f e e d w at er i ndeg . c e l s i u s

7   M w = 3 0 0 0 ;   / / mass o f w at ere va p or a te d i n kg / hr

8   M c = 4 1 0 ;   // c o a l f i r e d9   M a s h = 4 0 ;   // mass o f a sh i n kg / hr

10   P c a = 9 . 6 ;   //% o f c o mb u s ti b le i nas h

11   P m = 4 . 5 ;   //% o f m oi st ur e i n c o a l12   C = 3 0 5 0 0 ;   // c a l o r i f i c v aa l u e o f  

dr y c o al p e r k g13   C p s = 2 . 1 ;   // s p e c i f i c he at of  s u p e r h e a t e d s te am i n kJ / kgK

14

15

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16   // f rom stea m t a bl e , c o r r es p o n d i ng t o 13 bar ,

17   h f = 8 1 4 . 7 ;   / / i n k J / kg18   h f g = 1 9 7 0 . 7 ;   / / i n k J / kg19   T s = 1 9 1 . 6 ;   // i n deg . s e l s i u s20   h = h f + h f g + C p s * ( d s ) ;

21   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;

22   h t o t a l = h - h f 1 ;   // t o t a l h ea t s u p pl i e d t op ro du ce 1 kg o f stea m

23

24   M c 1 = M c * ( 1 - P m / 1 0 0 ) ;   // mass o f dry c o al i n kg25   M a = M w / M c 1 ;

26   E T A b = M a * ( h - h f 1 ) / C ;   // e f f i c i e n c y o f b o i l e r

p l an t i n c l u d i n g s u p er h e at e r27

28   M c o m = M a s h * P c a / 1 0 0 ;   // Mass o f c o mb u s ti b l e i na sh p er hr

29   / / t h e c om bu st ib l e p r e s en t i n as h i s p r a c t i c a l l yc ar bo n and i t s v a lu e may b e t ak en a s 3 38 /6 0 kJ / kg

30   // h ea t a c t u a l l y s u p pl i e d pr hr=h ea t o f dr y c oa l−h e a to f c om b us t i bl e i n a sh

31   H s u p p = M c 1 * C - M c o m * 3 3 8 6 0 ;   // h ea t a c t u a l l y s u p p l i e dpr hr

32   H u s e = M w * ( h - h f 1 ) ;  // h ea t u s e f u l l y u t i l i s e di n b o i l e r pr h r

33

34   E T A c = H u s e / H s u p p ;   // e f f i c i e n c y o f b o i l e ra nd f u r n a c e c om bi ne d

35

36   printf ( ’ ( i ) The E f f i c i e n c y o f b o i l e r p la nti n c l u d i n g s u p e r h ea t e r i s : %5 . 3 f o r %2 . 1 f p e r ce n t .\n ’ , E T A b , ( E T A b * 1 0 0 ) ) ;

37   printf ( ’ ( i i ) The E f f i c i e n c y o f t he b o i l e r andf u r n a c e c om bi ned i s : %5 . 3 f o r %2 . 1 f p e r c e n t .   \n ’ ,

E T A c , ( E T A c * 1 0 0 ) ) ;

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Scilab code Exa 6.11  Example 11

1   clc

2   clear

3   //DATA GIVEN4   M s = 5 0 0 0 ;   // mass o f stea m g e n er a t ed i n

k g / h r5   M f = 7 0 0 ;   // r a t e o f c o a l f i r i n g i n kg /

hr6   C = 3 1 4 0 2 ;   // h i g h e r c a l o r i f i c va lu e (HCV

) o f c o a l i n k J / kg7   x = 0 . 9 2 ;   // q u a l i t y o f stea m

8   p = 1 2 ;   // s tea m p r e s s u r e i n b ar9   T f w = 4 5 ;   // f e e d w at er temp . i n deg

c e l s i u s10

11   // f rom stea m t a bl e , c o r r es p o n d i ng t o 12 bar ,12   h f = 7 9 8 . 4 ;   / / i n k J / kg13   h f g = 1 9 8 4 . 3 ;   / / i n k J / kg14   h = h f + x * h f g ;   / / i n k J / kg15   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;   // h ea t of f e e d w a te r i n kJ /

kg16   M a = M s / M f ;

  // i n kg p er kg o f f u e l17   M e = M a * ( h - h f 1 ) / 2 2 5 7 ;   // ( kg o f s team ) / ( kg o f f u e l )18   e t a = M a * ( h - h f 1 ) / C ;   // t he rm al e f f i c i e n c y19

20   printf ( ’ ( i ) The E q u i v al e n t e v a po r a t io n , Me i s : %5 . 3f ( k g o f s team ) / ( kg o f c o a l ) .   \n ’ , M e ) ;

21   printf ( ’ ( i i ) The B o i l e r e f f i c i e n c y i s : %5 . 3 f o r %2. 1 f p e r c e n t .   \n ’ , e t a , e t a * 1 0 0 ) ;

Scilab code Exa 6.12  Example 12

1   clc

2   clear

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3   //DATA GIVEN

4   h s u p = 3 3 7 3 . 7 ;   / / e n t h a l p y o f s te am ( a t10 0 bar , 5 0 0 deg . c e l s i u s ) i n kJ / kg5   h f 1 = 6 7 7 ;   // e n th a lp y o f f e e d w at er

( a t i n l e t temp . 160 deg . c e l s i u s ) i n kJ /kg6   h f = 1 4 0 7 . 6 5 ;   // e n n th a l py o f s a t u r a t e d

l i q u i d a t 100 ba r i n kJ /kg7   h g = 2 7 2 4 . 7 ;   // e n n th a l py o f s a t u r a t e d

va po ut a t 10 0 b ar i n kJ / kg8   M s = 1 0 0 0 0 0 ;   // r a t e o f s te am

g e n e r a t i o n i n kg / hr9   e t a = 8 8 ;   // e f f i c i e n c y o f steam

g e n e r a t i o n10   C = 2 1 0 0 0 ;   / / c a l o r i f i c v a l u e o f f u e l

i n kJ / kg11

12   / / e t a =( h e a t a b s o r be d by s te am p e r h r ) / ( h e a t a dd ed byf u e l p er h ou r )

13   m = M s * ( h s u p - h f 1 ) / ( C * ( e t a / 1 0 0 ) ) ;   / / f u e l b u rn i ngr a t e i n kg / hr

14   h t o t a l = h s u p - h f 1 ;   // t o t a l h ea ts u p p l i e d t o stea m f o rm a ti o n

15   P e c = ( h f - h f 1 ) / h t o t a l ;  / /% o f h e ata b so r be d i n e c o n om i s e r

16   P e v = ( h g - h f ) / h t o t a l ;   / /% o f h e ata bs o rb ed i n e v a po r a to r

17   P s = ( h s u p - h g ) / h t o t a l ;   / /% o f h e ata bs o rb ed i n s u p e r h ea t e r

18

19   printf ( ’ ( i ) The F ue l b u rn i ng r a t e , m i s : %5 . 1 f kJ /h.   \n ’ , m ) ;

20   printf ( ’ ( i i ) The P er c en t ag e o f h ea t a bs o rb ed i ne c o n om i s e r i s : %5 . 4 f o r %5 . 2 f p e r c e n t .\ n ’ , P e c , (

P e c * 1 0 0 ) ) ;21   printf ( ’ The P e r c e n t a g e o f he a t ab s o r b e d i n

e v a p o r a t o r i s : %5 . 4 f o r %5 . 2 f p e r c e n t .\ n ’ , P e v , (

P e v * 1 0 0 ) ) ;

22   printf ( ’ The P e r c e n t a g e o f he a t ab s o r b e d i n

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s u p e r h e a t e r i s : %5 . 4 f o r %5 . 2 f p e r c e n t . \ n ’ , P s , ( P s

* 1 0 0 ) ) ;

Scilab code Exa 6.13  Example 13

1   clc

2   clear

3   //DATA GIVEN4   //BOILER

5   M w = 2 0 6 0 ;   // mass o f f e e d w at er6   M c = 2 2 7 ;   // mass o f c o a l s u p p li e d i n kg / hr7   C = 3 0 0 0 0 ;   / / c a l o r i f i c v a l u e o f c o a l i n kJ /

kg8   h s = 2 7 5 0 ;   / / e n t ha l p y o f s te am p ro du ce d i n

k J /k g9   h f w = 3 9 8 ;   // e n th a lp y o f f e e d w at er

10   //ECONOMISER11   T w i n = 1 5 ;   // temp . o f f e e d w at er e n t e r i n g

e co no mi se r i n deg c e l s i u s12   T w o u t = 9 5 ;   // temp . o f f e e d w at er l e a v i n g

e co no mi se r i n deg c e l s i u s13   T g o u t = 1 8 ;   / / a t m o s p h e r i c t em p .14   T g i n = 3 7 0 ;   // temp . o f e n t e r i n g f l u e g a s es15   M f g = 4 0 7 5 ;   // mass o f f l u e g a s e s16   // assumi ng Cpw and Cpg ,17   C p w = 4 . 1 8 7 ;

18   C p g = 1 . 0 1 ;

19

20   E T A b = M w * ( h s - h f w ) / ( M c * C ) ;

// e f f i c i e n c y o f  

b o i l e r21   E T A e = M w * C p w * ( T w o u t - T w i n ) / ( M f g * C p g * ( T g i n - T g o u t ) ) ;

// e f f i c i e n c y o f e co no mi se r22

23   printf ( ’ ( i ) The B o i l e r e f f i c i e n c y i s : %5 . 4 f o r %2 . 2

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f p e r ce n t .   \n ’ , E T A b , ( E T A b * 1 0 0 ) ) ;

24   printf ( ’ ( i i ) The E co no mi se r e f f i c i e n c y i s : %5 . 3 f o r%2 . 1 f p e r c e n t .   \n ’ , E T A e , ( E T A e * 1 0 0 ) ) ;

Scilab code Exa 6.14  Example 14

1   clc

2   clear

3   //DATA GIVEN

4   T f w = 5 0 ;   / /mean f e e d w at er temp . i n d egc e l s i u s5   p = 5 ;   / /mean s te am p r e s s u r e i n b ar6   x = 0 . 9 5 ;   // d r yn e s s f r a c t i o n o f stea m7   M c = 6 0 0 ;   / / c o a l c o ns u mp t io n kg / h r8   C = 3 0 4 0 0 ;   / / c a l o r i f i c v a l u e o f c o a l i n kJ /

kg9   M s = 4 8 0 0 ;   // f e ed w at er s u p p l i e d t o b o i l e r

i n kg / h r10

11   // f rom stea m t a bl e , c o r r es p o n d i ng t o 12 bar ,

12   h f = 6 4 0 . 1 ;   / / i n k J / kg13   h f g = 2 1 0 7 . 4 ;   / / i n k J / kh14   h = h f + x * h f g ;   / / i n k j / k g15   h f 1 = 4 . 1 8 * ( T f w - 0 ) ;

16

17   M a = M s / M c ;   // i n kg p e r kg o f f u e l18   M e = M a * ( h - h f 1 ) / 2 2 5 7 ;   // ( kg o f stea m ) / ( kg o f f u e l )19

20   printf ( ’ The E q ui v a le n t e v a p or a t i on fro m and a t 1 00deg c e l s i u s , Me i s : %5 . 3 f ( k g o f s team ) / ( kg o f  

c o al ) .\ n ’ , M e ) ;

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Chapter 7

Internal Combustion Engines

Scilab code Exa 7.1  Example 1

1   clc

2   clear

3   //DATA GIVEN4   P m i = 6 ;   // mean e f f e c t i v e

p r e s s u r e i n ba r5   N = 1 0 0 0 ;   / / e n g i n e s p ee d i n R . P .

M.6   D = 0 . 1 1 ;   // d i am et er o f p i s t o n

i n m7   L = 0 . 1 4 ;   // s t r o k e l e ng t h i n m8   n = 1 ;   // no . o f c y l i n d e r s9   k = 1 ;   / / f o r 2− s t r o k e

c y l i n d e r10

11   // INDICTED POWER , I . P. = ( n∗PMI∗ l ∗A∗N∗k ∗10) /6 kW12   A = ( % p i / 4 ) * ( D ^ 2 ) ;

13   I P = ( n * P m i * L * A * N * k * 1 0 ) / 6 ;14

15   printf ( ’ The I n d i c t e d Power d e v e l o p e d i s : %2 . 1 f kW. ’ ,

I P ) ;

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Scilab code Exa 7.2  Example 2

1   clc

2   clear

3   //DATA GIVEN4   //L=1.5D5   n = 4 ;   // no . o f c y l i n d e r s6   P = 1 4 . 7 ;   / / po wer d e v el o p e d i n

kW7   N = 1 0 0 0 ;   / / e n g i n e s p ee d i n R . P .

M.8   P m i = 5 . 5 ;   // mean e f f e c t i v e

p r e s s u r e i n ba r9   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r10

11   // INDICTED POWER, I . P. = ( n∗PMI∗ l ∗A∗N∗k ∗10) /6 kW12   //A=(p i /4 ) ∗Dˆ2 ,13   //L=1.5D,

14   D = ( ( 6 * P ) / ( 1 0 * k * N * n * P m i * 1 . 5 * ( % p i / 4 ) ) ) ^ ( 1 / 3 ) ;   //b or e d ia me te r i n m

15   L = 1 . 5 * D ;   //l e n gt h o f s t r o k e i n m

16

17   printf ( ’ The B or e d i a m e t e r i s : %5 . 2 f mm. \ n ’  , ( D * 1 0 0 0 ) )

;

18   printf ( ’ The S t o ke l e n g t h i s : %5 . 2 f mm. \ n ’  , ( L * 1 0 0 0 ) )

;

Scilab code Exa 7.3  Example 3

1   clc

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2   clear

3   //DATA GIVEN4   D b = 0 . 6 ;   / / d i a me t er o f b ra k ew he el i n m

5   d = 0 . 0 2 6 ;   // d i am et er o f r op e i nm

6   W = 2 0 0 ;   // d ead l o ad on t heb ra ke i n N

7   S = 3 0 ;   / / s p r i n g b a l a n c er e a d i ng i n N

8   N = 4 5 0 ;   / / e n g i n e s p ee d i n R . P .M.

910   // Br ak e P ow er , B. P . = (W−S ) ( p i ) (Db+d )N/ ( 6 0∗1 0 0 0 ) kW11   B P = ( W - S ) * ( % p i ) * ( D b + d ) * N / ( 6 0 * 1 0 0 0 ) ;

12

13   printf ( ’ The B ra k e Power , B . P . i s : %2 . 1 f kW.\ n ’ , B P ) ;

Scilab code Exa 7.4  Example 4

1   clc2   clear

3   //DATA GIVEN4   T = 1 7 5 ;   / / t o r q ue d ue t o b ra k e l o a d

in Nm5   N = 5 0 0 ;   / / e n g i n e s p e ed i n R . P .M.6

7   / / B r a k e P owe r , BP = ( 2∗ p i )NT/( 60 ∗1 0 0 0 ) kW8   B P = ( 2* % p i )* N * T / (6 0 *1 0 00 ) ;

9

10   printf ( ’ The B ra k e Power , B . P . i s : %4 . 2 f kW.\ n ’ , B P ) ;

Scilab code Exa 7.5  Example 5

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1   clc

2   clear3   //DATA GIVEN4   D = 0 . 3 ;   / / b o re o f e n g i n e

c y l i n d e r i n m5   L = 0 . 4 5 ;   // s t r o k e l e ng t h i n m6   N = 3 0 0 ;   / / e n g i n e s p ee d i n R . P .

M.7   P m i = 6 ;   // mean e f f e c t i v e

p r e s s u r e i n ba r8   N B L = 1 . 5 ;   / / Net b ra k e l o a d (W−S )

i n kN

9   D b = 1 . 8 ;   / / d i a me t er o f b ra k edrum

10   d = 0 . 0 2 ;   / / b r ak e r o pe d i a m et e r11   n = 1 ;   // no . o f c y l i n d e r s12   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r13

14   // INDICTED POWER , I . P. = ( n∗PMI∗ l ∗A∗N∗k ∗10) /6 kW15   A = ( % p i / 4 ) * ( D ^ 2 ) ;

16   I P = ( n * P m i * L * A * N * k * 1 0 ) / 6 ;

17   B P = N B L * ( % p i ) * ( D b + d ) * N / ( 6 0 ) ;

18   e t a = B P / I P ;   / / m e c h a n i c a le f f i c i e n c y

19

20   printf ( ’ ( i ) The I n d i c t e d Power , I . P . i s : %5 . 2 f kW .\n ’ , I P ) ;

21   printf ( ’ ( i i ) The B ra k e Power , B . P . i s : %5 . 2 f kW .   \n’ , B P ) ;

22   printf ( ’ ( i i i ) M ec ha ni ca l e f f i c i e n c y i s : %5 . 4 f o r %5. 2 f p e r c e n t . \ n ’ , e t a , ( e t a * 1 0 0 ) ) ;

Scilab code Exa 7.6  Example 6

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1   clc

2   clear3   //DATA GIVEN4   D = 0 . 2 ;   / / d i a me t er o f e n g i n e

c y l i n d e r i n m5   L = 0 . 3 5 0 ;   // l e ng t h o f s t r o k e i n

m6   P m i c o = 6 . 5 ;   // mean e f f e c t i v e

p r e s s u r e on c ov er s i d e i n b a r7   P m i c r = 7 ;   // mean e f f e c t i v e

p r e s s u r e on c r a n k s i d e i n b a r8   N = 4 2 0 ;   / / e n g i n e s p ee d i n R . P .

M.9   D r o d = 0 . 0 2 ;   // d i am et er o f p i s t o n

r o d i n m10   W = 1 3 7 0 ;   // d ead l o ad on t he

b ra ke i n N11   S = 1 4 5 ;   / / s p r i n g b a l a n c e

r e a d i ng i n N12   D b = 1 . 2 ;   / / d i a me t er o f b ra k e

w he el i n m13   d = 0 . 0 2 ;   // d i am et er o f r op e i n

m14   n = 1 ;   // no . o f c y l i n d e r s15   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r16

17   // INDICTED POWER , I . P. = ( n∗Pmi∗ l ∗A∗N∗k ∗10) /6 kW18   A c o = ( % p i / 4 ) * ( D ^ 2 ) ;   / / a r e a o f  

c y l i n d e r om c o ve r end i n mˆ219   A c r = ( % p i / 4 ) * ( D ^ 2 - D r o d ^ 2 ) ;   / / a r e a o f  

c y l i n d e r om c ra nk end i n mˆ220   I P c o = ( n * P m i c o * L * A c o * N * k * 1 0 ) / 6 ;   / / IP on c o v e r end

s i d e i n kW21   I P c r = ( n * P m i c r * L * A c r * N * k * 1 0 ) / 6 ;   / / IP on c ra n k end

s i d e i n kW22   I P t o t a l = I P c o + I P c r ;   // IP t o t a l i n kW23

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24   // Br ak e P ow er , B. P . = (W−S ) ( pi ) (Db+d )N/ ( 6 0∗1 0 0 0 ) kW

25   B P = ( W - S ) * ( % p i ) * ( D b + d ) * N / ( 6 0 * 1 0 0 0 ) ;26

27   e t a = B P / I P t o t a l ;   / / m e c h a n i c a le f f i c i e n c y

28

29   printf ( ’ M ec ha ni ca l e f f i c i e n c y i s : %5 . 4 f o r %5 . 2 f  p e r c e n t .\ n ’ , e t a , ( e t a * 1 0 0 ) ) ;

Scilab code Exa 7.7  Example 7

1   clc

2   clear

3   //DATA GIVEN4   I P = 3 0 ;   / / i n d i c t e d p ow er i n kW5   B P = 2 6 ;   / / B r a k e P ow er i n kW6   N = 1 0 0 0 ;   // e n g i n e s p ee d i n R . P .M

.7   F = 0 . 3 5 ;   // f u e l p e r b r ak e po we r

h o u r i n k g /BP/ h

8   C = 4 3 9 0 0 ;   // c a l o r i f i c v a l u e of  f u e l u se d i n kJ /kg

9

10   F c = F * B P ;   / / f u e l c o ns u mp t io n p e rhour

11   M f = F c / 3 6 0 0 ;

12   E T A t i = I P / ( M f * C ) ;   / / I n d i c t e d t h er m ale f i c i e n c y

13   E T A t b = B P / ( M f * C ) ;   / / B r ak e t h e r m a le f f i c i e n c y

14   E T A m = B P / I P ;   // M ec ha ni ca l e f f i c i e n c y15

16   printf ( ’ ( i ) The I n d i c te d t he rm al e f i c i e n c y i s : %5 . 3f o r %2 . 1 f p e r c e n t .   \n ’ ,ETAti ,(ETAti*100));

17   printf ( ’ ( i i ) The B ra ke t he rm al e f f i c i e n c y i s : %5 . 3 f  

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o r %2 . 1 f p e r c e n t .   \n ’ ,ETAtb ,(ETAtb*100));

18   printf ( ’ ( i i i ) M ec ha ni ca l e f f i c i e n c y i s : %5 . 3 f o r %2. 1 f p e r c e n t .   \n ’ , E T A m , ( E T A m * 1 0 0 ) ) ;

Scilab code Exa 7.8  Example 8

1   clc

2   clear

3   //DATA GIVEN

4   D b = 0 . 7 5 ;   / / d i a m et e r o f b r ak ep u l l ey i n m5   d = 0 . 0 5 ;   // d i am e te r o f r op e i n

m6   W = 4 0 0 ;   // d ead l o ad on t he

b ra ke i n N7   S = 5 0 ;   / / s p r i n g b a l a n c e

r e a d i ng i n N8   F c = 4 . 2 ;   / / f u e l c on su mp ti on i n

k g / h r9   N = 1 0 0 0 ;   / / r a t e d e n g i n e s p ee d

i n R . P . M .10   C = 4 3 9 0 0 ;   // c a l o r i f i c v a l u e of  

f u e l u se d i n kJ /kg11   n = 1 ;   // no . o f c y l i n d e r s12   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r13

14

15   // Br ak e P ow er , B. P . = (W−S ) ( pi ) (Db+d )N/ ( 6 0∗1 0 0 0 ) kW16   B P = ( W - S ) * ( % p i ) * ( D b + d ) * N / ( 6 0 * 1 0 0 0 ) ;

17   s f c = F c / B P ;   / / b r a k es p e c i f i c f u e l c o n s um p t io n i n k g /kWhr18   M f = F c / 3 6 0 0 ;

19   E T A t b = B P / ( M f * C ) ;   / / B r a k et he r ma l e f f i c i e n c y

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20

21   printf ( ’ ( i ) The B ra ke s p e c i f i c f u e l c on su mp ti o n , s .f . c ( b r a k e ) i s : %5 . 3 f k g /kWh .   \n ’ , s f c ) ;

22   printf ( ’ ( i i ) The B ra ke t he rm al e f f i c i e n c y i s : %5 . 3 f  o r %2 . 1 f p e r c e n t .   \n ’ ,ETAtb ,(ETAtb*100));

Scilab code Exa 7.9  Example 9

1   clc

2   clear3   //DATA GIVEN4   n = 6 ;   // no . o f c y l i n d e r s5   D = 0 . 0 9 ;   / / b o re o f e ac h

c y l i n d e r i n m6   L = 0 . 1 ;   // l e ng t h o f s t r o k e i n

m7   r = 7 ;   / / c o m p re s s i on r a t i o8   E T A r e l = 0 . 5 5 ;   // r e l a t i v e e f f i c i e n c y9   F s c = 0 . 3 ;   / / i n d i c a t e d s p e c i f i c

f u e l c o ns u mp t io n i n kg /kWh

10   P m i = 8 . 6 ;   / / i n d i c a t e d meane f f e c t i v e p r e s s u r e i n b ar

11   N = 2 5 0 0 ;   / / e n g i n e s p ee d i n R . P .M.

12   k = 0 . 5 ;   / / f o r 4− s t r o k ec y l i n d e r

13

14   / / A i r s t a nd a r d e f f i c i e n c y , ETAair =1−1/(r ˆ(gamma−1) )15   g = 1 . 4 ;   //gamma of a i r = 1. 416   E T A a i r = 1 - 1 / ( r ^ ( g - 1 ) ) ;

17   / / I n d i c a t e d t h e r m a l e f f i c i e n c y , E TA rel=ETAthi / ETA ai r;18   E T A t h i = E T A r e l * E T A a i r ;

19   / / I n d i c t e d t h e rm a l e f i c i e n c y , ETAthi=IP / ( Mf  ∗C)20   M f = F s c / 3 6 0 0 ;

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21   / / t a k i n g I P =1 ,

22   C = 1 / ( E T A t h i * M f ) ;   // c a l o r i f i c va lu e ink J /k g23   // INDICTED POWER , I . P. = ( n∗Pmi∗ l ∗A∗N∗k ∗10) /6 kW24   A = ( % p i / 4 ) * ( D ^ 2 ) ;

25   I P = ( n * P m i * L * A * N * k * 1 0 ) / 6 ;

26   F c = F s c * I P ;   // t o t a l f u e lc o ns u mp t io n i n kg / h r

27

28   printf ( ’ ( i ) The C a l o r i f i c v al ue o f c oa l , C i s : %5 . 0f k J / kg .   \n ’ , C ) ;

29   printf ( ’ ( i i ) The F u el c o ns u mp t io n i s : %5 . 2 f k g /h .   \

n ’ , F c ) ;30

31   //NOTE:32   / / a ns o f c a l o r i f i c v a l u e h e r e i s e xa ct , w h i l e i n TB

i t s r ou nded o f f v al ue

Scilab code Exa 7.10  Example 10

1   clc2   clear

3   //DATA GIVEN4   n = 4 ;   // no . o f c y l i n d e r s5   B P = 3 0 ;   / / B r a k e P ow er i n kW6   N = 2 5 0 0 ;   / / e n g i n e s p ee d i n R . P .

M.7   P m i = 8 ;   // mean e f f e c t i v e

p r e s s u r e i n ba r8   E T A m = 0 . 8 ;   / / m e c h a n i c a l

e f f i c i e n c y9   E T A t h b = 0 . 2 8 ;   / / b r a k e t h e rm a le f f i c i e n c y

10   C = 4 3 9 0 0 ;   // c a l o r i f i c v al ue o f  f u e l u se d i n kJ /kg

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11   k = 1 ;   / / f o r 2− s t r o k e

c y l i n d e r12

13   // me c han i c a l e f f i c i e n c y , ETAm=BP/IP14   I P = B P / E T A m ;

15   // INDICTED POWER , I . P. = ( n∗PMI∗ l ∗A∗N∗k ∗10) /6 kW16   //L=1.5D,17   D = ( ( 6 * I P ) / ( 1 0 * k * N * n * P m i * 1 . 5 * ( % p i / 4 ) ) ) ^ ( 1 / 3 ) ;   //

b or e d ia me te r i n m18   L = 1 . 5 * D ;   //

l e n gt h o f s t r o k e i n m19   / / B r a ke t h e r m a l e f f i c i e n c y , ETAtb=BP / ( Mf  ∗C)

20   M f = B P / ( E T A t h b * C ) ;   //f u e l c on su mp ti on i n kg / h r

21

22   printf ( ’ ( i ) The B or e d i a me t er i s : %5 . 3 f m o r %2 . 0 f  mm. \ n ’ , D , ( D * 1 0 0 0 ) ) ;

23   printf ( ’ The St o k e l en gt h i s : %2 . 0 f mm. \ n ’  ,( L

* 1 0 0 0 ) ) ;

24   printf ( ’ ( i i ) The F ue l c on su mp ti on i s : %5 . 5 f kg / s o r%3 . 2 f k g / h r .   \n ’ , M f , ( M f * 3 6 0 0 ) ) ;

Scilab code Exa 7.11  Example 11

1   clc

2   clear

3   //DATA GIVEN4   n = 6 ;   // no . o f c y l i n d e r s5   P d i s p = 7 0 0 ;   // p i s t o n d i s p p er

c y l i n d e r i n cmˆ3

6   P = 7 8 ;   / / po wer d e v el o p e d i nkW7   N = 3 2 0 0 ;   / / e n g i n e s p ee d i n R . P .

M.8   M f = 2 7 ;   // mass o f f u e l u s e d i n

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k g / h r

9   C = 4 4 0 0 0 ;   // c a l o r i f i c v al ue o f  f u e l u se d i n kJ /kg10   a f r = 1 2 ;   // a i r f u e l r a t i o11   P a = 0 . 9 ;   // i n t a k e a i r p r e s s ur e

i n b ar12   T a = 3 2 + 2 7 3 ;   // i n t a k e a i r

t e mp e r ta u r e i n K13   R = 0 . 2 8 7 ;   // g as c on s t an t f o r a i r

i n k J / kgK14   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r

1516   M a = a f r * M f ;   / / ma ss o f  

a i r17   / / by e q . pa∗Va=Ma∗R∗Ta18   V a = M a * R * T a / P a / 1 0 0 ;   / / v ol um e o f  

i n t a k e a i r i n mˆ3/ h r19   V s w e p t = ( P d i s p / 1 0 ^ 6 ) * n * ( N / 2 ) * 6 0 ;   //v ol ume

s we pt i n mˆ 3/ h r20   E T A v o l = V a / V s w e p t ;   / / v o l u m e t r i c

e f f i c i e n c y21

22   / / B ra ke t h e rm a l e f f i c i e n c y , ETAbt=b r a ke wo rk / h e a ts u pp l i e d by t h e f u e l

23   E T A b t = P / ( M f * C / 3 6 0 0 ) ;

24   / / B r a k e P owe r , BP = ( 2∗ p i )N∗T b/( 60∗1 0 0 0 ) k W25   T b = P * 6 0 / ( 2 * % p i * N ) ;   / / b r a k e

t o r q u e i n kNm26

27   printf ( ’ ( i ) The V ol um et ri c e f f i c i e n c y i s : %5 . 3 f o r%5 . 1 f p e r c e n t .   \n ’ ,ETAvol ,(ETAvol*100));

28   printf ( ’ ( i i ) The Brake t he rm al e f f i c i e n c y i s : %5 . 4

f o r %5 . 2 f p e r c e n t .   \n ’ ,ETAbt ,(ETAbt*100));29   printf ( ’ ( i i i ) The B r ak e T or qu e i s : %5 . 4 f kNm .   \n ’ ,

T b ) ;

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Scilab code Exa 7.12  Example 12

1   clc

2   clear

3   //DATA GIVEN4   //L=1.5D5   n = 6 ;   // no . o f c y l i n d e r s6   V s = 1 . 7 5 ;   / / s t r o k e v ol um e i n

l i t r e s7   I P = 2 6 . 3 ;   / / po wer d e v el o p e d i n

kW8   N e = 5 0 4 ;   / / e n g i n e s p ee d i n R . P .

M.9   P m i = 6 ;   // mean e f f e c t i v e

p r e s s u r e i n ba r10   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r11

12   // INDICTED POWER , I . P. = ( n∗PMI∗ l ∗A∗N∗k ∗10) /6 kW

13   //L∗A=Vs14   N a = I P * 6 / ( n * P m i * ( V s / 1 0 ^ 3 ) * k * 1 0 ) ;   / / a c t u a l s p e ed

i n R . P . M15   F a = N a * n * k ;   // a c t u a l no . o f  

f i r e s i n o n e m i nu t e16   F e = N e * n / 2 ;   / / e x p e c t e d n o .

o f f i r e s i n o ne m in ut e17   F m = F e - F a ;   // m i s f i r e s p er

mi nut e18   F m a v g = F m / n ;   / / a vg . no . o f  

t im es e a c h c y l i n d e r m i s f i r e s i n one mi nut e19

20   printf ( ’ The Av er ag e no . o f t i me s e ac h c y l i n d e rm i s f i r e s i n one m in ut e i s : %1 . 0 f .\ n ’ , F m a v g ) ;

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Scilab code Exa 7.13  Example 13

1   clc

2   clear

3   //DATA GIVEN4   D = 0 . 0 7 5 ;   / / b o re i n m5   L = 0 . 0 9 ;   // s t r o k e l e ng t h i n m6   n = 4 ;   // no . o f c y l i n d e r s7   e r a r = 3 9 / 8 ;   // e ng i ne t o r e a r a x l e

r a t i o =3 9: 88   D w = 0 . 6 5 ;   / / w he el d i a m et e r w it h

t y r e f u l l y i n f l a t e d i n m9   F c = 0 . 2 2 7 ;   / / p e t r o l c o ns u mp t io n

f o r a d i s t a n ce o f 3 . 2 km a t a s pe e d o f 48 km/ hr10   P m i = 5 . 6 2 5 ;   // mean e f f e c t i v e

p r e s s u r e i n ba r11   C = 4 3 4 7 0 ;   // c a l o r i f i c v al ue o f  

f u e l u se d i n kJ /kg12   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r13

14   s = 4 8 * 1 0 0 0 / 6 0 ;   // s pe ed o f c a r i n m/mi n

15   / / i f Nt r e v a r e made by t y r e p e r mi nu te , s p ee d=p i ∗Dw∗Nt

16   N t = s / ( % p i * D w ) ;   //R.P.M.17   // a s e n g i ne t o r e a r a xl e r a t i o i s 3 9: 818   N e = e r a r * N t ;   // s pe ed o f e n f i n e

s h a f t i n R . P .M.19   // INDICTED POWER , I . P. = ( n∗PMI∗ l ∗A∗N∗k ∗10) /6 kW20   A = ( % p i / 4 ) * ( D ^ 2 ) ;

21   I P = ( n * P m i * L * A * N e * k * 1 0 ) / 6 ;

22

23   s = s / 1 0 0 0 ;   / / s p ee d o f c a r i n km/

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mi n

24   t = 3 . 2 / s ;   // t im e i n min f o rc o v e r in g 3 . 2 km25   / / p e t r o l c o ns ump ti on f o r a d i s t a nc e o f 3 . 2 km a a t a

s pe ed o f 48 km/ h r i s 0 . 2 2 7 kg26   M f = F c / ( t * 6 0 ) ;   / / f u e l co ns um ed p e r

s e c27   E T A t h i = I P / ( M f * C ) ;   // I n d i c a t e d f u e l

e f f i c i e n c y28

29   printf ( ’ ( i ) The I n d i c a t e d Power d e v el o p e d i s : %5 . 2 f  kW.   \n ’ , I P ) ;

30   printf ( ’ ( i i ) The I n d i ca t e d t he rm al e f f i c i e n c y i s :%1 . 3 f o r %2 . 1 f p e r c e n t .   \n ’ ,ETAthi ,(ETAthi*100));

Scilab code Exa 7.14  Example 14

1   clc

2   clear

3   //DATA GIVEN

4   D = 0 . 2 5 ;   // c y l i n d e r d i am e te r i nm

5   L = 0 . 4 ;   // s t r o k e l e ng t h i n m6   P m g = 7 ;   // G ro ss mean e f f e c t i v e

p r e s s u re i n b ar7   P m p = 0 . 5 ;   // Pumping mean

e f f e c t i v e p r e s s u r e i n b ar8   N = 2 5 0 ;   / / e n g i n e s p ee d i n R . P .

M.9   N B L = 1 0 8 0 ;   / / n e t l o a d on t h e

b r a ke (W−S ) i n N10   D b = 1 . 5 ;   // e f f e c t i v e d ia me te ro f t he b r a ke i n m

11   F c = 1 0 ;   // f u e l u s e d p er hr i nkg

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12   C = 4 4 3 0 0 ;   // c a l o r i f i c v al ue o f  

f u e l u se d i n kJ /kg13   n = 1 ;   // no . o f c y l i n d e r s14   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r15

16   // INDICTED POWER , I . P. = ( n∗PMI∗ l ∗A∗N∗k ∗10) /6 kW17   P m = P m g - P m p ;

18   A = ( % p i / 4 ) * ( D ^ 2 ) ;

19   I P = ( n * P m * L * A * N * k * 1 0 ) / 6 ;

20   B P = N B L * ( % p i ) * ( D b ) * N / ( 6 0 * 1 0 0 0 ) ;

21   E T A m = B P / I P ;   / / m e c h a n i c a l

e f f i c i e n c y22   M f = F c / 3 6 0 0 ;

23   E T A t h i = I P / ( M f * C ) ;   / / I n d i c a t e d t h er m ale f f i c i e n c y

24

25   printf ( ’ ( i ) The I n d i c a t e d Power , I . P . i s : %5 . 2 f kW.\n ’ , I P ) ;

26   printf ( ’ ( i i ) The B ra k e Power , B . P . i s : %2 . 1 f kW .   \n’ , B P ) ;

27   printf ( ’ ( i i i ) M ec ha ni ca l e f f i c i e n c y i s : %5 . 3 f o r %2

. 1 f p e r c e n t . \ n ’, E T A m , ( E T A m * 1 0 0 ) ) ;

28   printf ( ’ ( i v ) I n d i ca t e d t he rm al e f f i c i e n c y i s : %5 . 3 f  o r %2 . 1 f p e r c e n t .\ n ’ ,ETAthi ,(ETAthi*100));

Scilab code Exa 7.15  Example 15

1   clc

2   clear

3   //DATA GIVEN4   E T A t h b = 3 0 ;   / / B r ak e t h e r m a le f f i c i e n c y i n %

5   a f r = 2 0 ;   // a i r f u e l r a t i o byw e i g h t

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6   C = 4 1 8 0 0 ;   // c a l o r i f i c v al ue o f  

f u e l u se d i n kJ /kg7

8   / / B r a ke t h e r m a l e f f i c i e n c y , ETAthb=w or k p r o d uc e d /h ea t s u p p l i e d

9   w o r k = ( E T A t h b / 1 0 0 ) * C ;   / / wo rk p r od u ce d p e r k go f f u e l

10   / /STP c o n d i t i o n s r e f e r t o 1 . 01 3 2 b ar and 15 degc e l s i u s

11   m = a f r ;   // mass o f a i r p er kgo f f u e l

12   R = 2 8 7 ;

13   V = m * R * ( 1 5 + 2 7 3 ) / ( 1 . 0 1 3 2 * 1 0 ^ 5 ) ;   // v olume o f a i r u se d14   / / B ra ke mean e f f e c t i v e p r e s s u r e , Pmb=wo rk d on e /

c y l i n d e r vo lu me15   P m b = ( w o r k * 1 0 0 0 ) / ( V * 1 0 ^ 5 ) ;

16

17   printf ( ’ The B ra ke mean e f f e c t i v e p r e s s u r e , Pmb i s :%2 . 2 f b a r .\ n ’ , P m b ) ;

Scilab code Exa 7.16  Example 16

1   clc

2   clear

3   //DATA GIVEN4   V 1 = 0 . 2 1 6 ;   / / g a s c on su mp ti on i n m

ˆ3/min5   P 1 = 7 5 ;   // g a s t em p er a tu re i n

mm o f w a t e r6   T 1 = 1 7 + 2 7 3 ;   // g a s t em p er ta u re i n K

7   m = 2 . 8 4 ;   / / a i r c o ns u mp t io n i nkg/min8   T a = 1 7 + 2 7 3 ;   // a i r t em p er ta u re i n K9   b r = 7 4 5 ;   // b a ro me te r r e a d in g i n

mm of Hg

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10   D = 0 . 2 5 ;   / / b o re o f e n g i n e

c y l i n d e r i n m11   L = 0 . 4 7 5 ;   // s t r o k e l e ng t h i n m12   N = 2 4 0 ;   / / e n g i n e s p ee d i n R . P .

M.13   R = 2 8 7 ;   // g as c on s t an t f o r a i r

i n J / kgK14   n = 1 ;   // no . o f c y l i n d e r s15   k = 1 ;   / / f o r 2− s t r o k e

c y l i n d e r16

17   P 1 = b r + P 1 / 1 3 . 6 ;   // p r e s s ur e o f t he g as

18   // at NTP19   P 2 = 7 6 0 ;   //mm o f Hg20   T 2 = 0 + 2 7 3 ;   / / i n K21   //P1∗V1/T1=P2∗V2/T222   V 2 = P 1 * V 1 * T 2 / ( P 2 * T 1 ) ;   / / vo lu me o f g a s u se d

at NTP i n mˆ323   V g = V 2 / ( N / 2 ) ;   // g a s u se d p er s t r o k e

i n m ˆ 324

25   //PV=mRT26   P 2 = 1 . 0 1 3 2 * 1 0 ^ 5 ;

27   V = m * R * T 2 / P 2 ;   / / v ol um e o c c u p i e d bya i r i n mˆ 3/ min

28   V a = V / ( N / 2 ) ;   // a i r u se d p er s t r o k ei n m

29

30   V m i x = V g + V a ;   / / m i xt u re o f g a s anda i r i n mˆ3

31

32   / / ETAvol=( a c t u a l v ol um e o f m i x tu r e drawn p e r s t r o k ea t NTP) / ( s w e p t v o lu m e o f s y s t e m )

33   E T A v o l = V m i x / ( ( % p i / 4 ) * D ^ 2 * L ) ;34

35   printf ( ’ The V ol um et ri c e f f i c i e n c y i s : %3 . 3 f o r %3 . 1f p e r ce n t .   \n ’ ,ETAvol ,(ETAvol*100));

112

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Scilab code Exa 7.17  Example 17

1   clc

2   clear

3   //DATA GIVEN4   t = 1 ;   / / d u r a t i o n o f t r i a l i n

hr5   N = 1 4 0 0 0 ;   / / r e v o l u t i o n s6   m c = 5 0 0 ;   // no . o f m is se d c y c l e s7   N B L = 1 4 7 0 ;   / / Net b ra k e l o a d (W−S )

i n N8   P m i = 7 . 5 ;   // mean e f f e c t i v e

p r e s s u r e i n ba r9   V g = 2 0 0 0 0 / 3 6 0 0 ;   / / g a s c on su mp ti on i n

l i t r e s / s10   C = 2 1 ;   //LCV o f g as a t s i p p l y

c o n d i t i o n s i n kJ / l i t r e11   D = 0 . 2 5 ;   // c y l i n d e r d i am e te r i n

m

12   L = 0 . 4 ;   // s t r o k e l e ng t h i n m13   C b = 4 ;   // e f f e c t i v e b ra ke

c i r cu m f er e n ce i n m14   r = 6 . 5 ;   / / c o m p re s s i on r a t i o15   n = 1 ;   // no . o f c y l i n d e r s16   k = 0 . 5 ;   / / f o r 4− s t r o k e

c y l i n d e r17

18   / / gamma f o r a i r , g = 1 .419   g = 1 . 4 ;

20

21   // INDICTED POWER , I . P. = ( n∗PMI∗ l ∗A∗N∗k ∗10) /6 kW22   N k = ( N * k - m c ) / 6 0 ;   / / ( N∗k )−w or ki ng c y c l e s

/min23   A = ( % p i / 4 ) * ( D ^ 2 ) ;

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24   I P = ( n * P m i * L * A * N k * 1 0 ) / 6 ;

25   N = N / 6 0 ;26   B P = N B L * ( C b ) * N / ( 6 0 * 1 0 0 0 ) ;

27   e t a = B P / I P ;   / / m e c h a n i c a le f f i c i e n c y

28   E T A t h i = I P / ( V g * C ) ;   / / I n d i c a t e d t h er m ale f f i c i e n c y

29

30   / / r e l a t i v e e f f i c i e n c y , E TA re l=ETAthi / ETAas31   //ETAas=1−1/(r ˆ( g−1) )32   E T A a s = 1 - 1 / ( r ^ ( g - 1 ) ) ;   // ai r −s t a n d a r d

e f f i c i e n c y

33   E T A r e l = E T A t h i / E T A a s ;   // r e l a t i v e e f f i c i e n c y34

35   printf ( ’ ( i ) The I n d i c a t e d Power , I . P . i s : %5 . 2 f kW.   \n ’ , I P ) ;

36   printf ( ’ ( i i ) The B ra ke Power , B . P . i s : %5 . 2 f kW.   \n ’ , B P ) ;

37   printf ( ’ ( i i i ) M ec ha ni ca l e f f i c i e n c y i s : %5 . 3 f o r %2. 1 f p e r c e n t . \ n ’ , e t a , ( e t a * 1 0 0 ) ) ;

38   printf ( ’ ( i v ) The I n di c at e d t he r ma l e f f i c i e n c y i s :%2 . 2 f o r %2 . 0 f p e r c e n t .   \n ’ ,ETAthi ,(ETAthi*100));

39   printf ( ’ ( v ) The R e l at i v e e f f i c i e n c y i s : %2 . 3 f o r%2 . 1 f p e r c e n t .   \n ’ ,ETArel ,(ETArel*100));

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Chapter 10

Air Compressors

Scilab code Exa 10.1  Example 1

1   clc

2   clear

3   //DATA GIVEN4   V 1 = 1 ;   // v olume o f a i r

t a k e n i n mˆ 3 /mim5   p 1 = 1 . 0 1 3 ;   // i n t a k e p r e s s ur e i n

b a r6   T 1 = 1 5 + 2 7 3 ;   / / i n t a k e t e m p e ra t u r e

i n K7   p 2 = 7 ;   // d e l i v e r y p r e s s u r e

i n b ar8   t = 1 * 6 0 ;   // t i me i n s e co n ds9   / / l a w o f c o m p r e s s i o n , pV ˆ1 . 35 =C

10   n = 1 . 3 5 ;

11   R = 2 8 7 ;

12

13   m = p 1 * 1 0 ^ 5 * V 1 / R / T 1 ;   // mass o f a i rd e l i v e r e d i n kg / min14

15   // ( T2/T1) =( p2/p1) ˆ( ( n−1)/n) ;16   T 2 = T 1 * ( p 2 / p 1 ) ^ ( ( n - 1 ) / n ) ;   / / d e l i v e r y temp . T2

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i n K

1718   W = ( n ) / ( n - 1 ) * m * R * ( T 2 - T 1 ) / 1 0 0 0 ;   // i n d i c a t e d work i n

kJ/min19

20   I P = W / t ;   // i n d i c a t e d p ower i nkW

21

22   printf ( ’ The I n d i c a t e d p ower , IP i s : %1 . 2 f kW .   \n ’ ,

I P ) ;

Scilab code Exa 10.2  Example 2

1   clc

2   clear

3   / / c o n t i n u e d f ro m E xa mp le 14   //DATA GIVEN5   V = 1 ;   // v olu me d e a l t w it h

p e r min a t i n l e t i n mˆ 3/ mim6   V c = 1 / 3 0 0 ;   / / v o lu me d ra wn i n

p e r c y c l e , i n mˆ 3/ c y c l e7   r = 1 . 5 ;   // s t r o k e t o b or e

r a t i o8   E T A c = 0 . 8 5 ;   / / m e c h a n i c a l

e f f i c i e n c y o f t h e c om pr es so r9   E T A m t = 0 . 9 0 ;   / / m e c h a n i c a l

e f f i c i e n c y o f t h e m otor t r an s m i s s i o n10

11   / / c y l i n d e r v ol um e , Vc=( p i / 4 ) Dˆ 2∗L12   D = [ ( V c * 4 / % p i ) / r ] ^ ( 1 / 3 ) ;   // b o re i n m

1314   / / f r om e xa mp le 115   P i = 4 . 2 3 / E T A c ;   // p ower i n pu t t o t he

c o m p r e s so r i n kW16   M P = P i / E T A m t ;   / / m o to r p ow er i n kW

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17

18   printf ( ’ ( i ) The C y l i n d e r b or e , D i s : %3 . 1 f mm.   \n ’  ,(D * 1 0 0 0 ) ) ;

19   printf ( ’ ( i i ) The M ot or p ow er i s : %1 . 2 f kW .   \n ’ , M P ) ;

Scilab code Exa 10.3  Example 3

1   clc

2   clear

3   //DATA GIVEN4   T 1 = 2 0 + 2 7 3 ;   / / t e m p e ra t u r e i n K5   p 1 = 1 ;   // p r e s s u r e i n b ar6   p 2 = 1 0 ;   // p r e s s u r e i n b ar7   C v = 0 . 7 1 8 ;   // i n k J /kgK8

9   / / l a w o f c o m p r e s s i o n , pV ˆ1 . 2=C10   n = 1 . 2 ;

11   R = 0 . 2 8 7 ;   // i n k J /kgK12

13   // ( T2/T1) =( p2/p1) ˆ( ( n−1)/n) ;

14   T 2 = T 1 * ( p 2 / p 1 ) ^ ( ( n - 1 ) / n ) ;   / / temp . T2 i n K15   m = 1 ;

16   W = ( n ) / ( n - 1 ) * m * R * T 1 * [ ( p 2 / p 1 ) ^ ( ( n - 1 ) / n ) - 1 ] ;   //work done p er kg o f a i r ( kJ /kg o f a i r )

17

18   / / By t h e F i r s t Law o f T he rm od yn am ic s19   / / h e a t t r a n s f e r r e d d u r i n g c o m p r e s s i o n , Q=W+DU20   //Q=(p1V1−p2V2) /( n−1)+Cv(T2−T1 )21   //Q=(T2−T1 ) ∗ [ Cv−R / ( n−1) ]22   Q = ( T 2 - T 1 ) * [ C v - R / ( n - 1 ) ] ;

2324   printf ( ’ ( i ) The T em pe ra tu re a t t h e end o f  c o mp r es s io n i s : %3 . 0 f K o r %3 . 0 f deg . c e l s i u s .   \n’ , T 2 , ( T 2 - 2 7 3 ) ) ;

25   printf ( ’ ( i i ) The Work d on e d u r i n g c o m p r e s s i o n p e r

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kg o f a i r i s : %3 . 2 f kJ /kg o f a i r .   \n ’ , W ) ;

26   printf ( ’ The Heat t r a n s f e r r e d d u r i n gc om pr es si on p er kg o f a i r i s : %2 . 2 f kJ /kg o f a i r .\n ’ , Q ) ;

27   printf ( ’ ( N e g a t i v e s i g n i n d i c a t e s h e a tREJECTION . )   \n ’ ) ;

Scilab code Exa 10.4  Example 4

1   clc2   clear

3   //DATA GIVEN4   p 1 = 1 ;   // s u c t i o n p r e s s u r e

i n b ar5   T 1 = 2 0 + 2 7 3 ;   / / s u c t i o n

t e mp e r at u r e i n K6   p 2 = 6 ;   // d i s c h a r g e p r e s s u r e

i n b ar7   T 2 = 1 8 0 + 2 7 3 ;   / / d i s c h a r g e

t e mp e r at u r e i n K

8   N = 1 2 0 0 ;   / / s p e ed o f  c o m p r e ss o r i n R . P . M.

9   P s h a f t = 6 . 2 5 ;   / / s h a f t p ow er i n kW10   M a = 1 . 7 ;   // mass o f a i r

d e l i v e r e d i n kg / min11   D = 0 . 1 4 ;   / / d i a m e t e r i n m12   L = 0 . 1 ;   // s t r o k e i n m13   R = 2 8 7 ;   // i n k J /kgK14

15   V d = ( % p i / 4 ) * D ^ 2 * L * N ;   / / d i s p l a c e m e n t

volume f o r s i n g l e a c t i n g c om p re ss o r i n mˆ3 /min16   F A D = M a * R * T 1 / p 1 / 1 0 ^ 5 ;   //mˆ3/min17   E T A v o l = F A D / V d * 1 0 0 ;   // a c t u a l v o l u m e t r i c

e f f i c i e n c y18

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19   // ( T2/T1) =( p2/p1) ˆ( ( n−1)/n) ;

20   n = 1 / [ 1 - ( log ( T 2 / T 1 ) / log ( p 2 / p 1 ) ) ] ;   / / i n d e x o f  c o m p r e s s i o n , n21

22   I P = ( n ) / ( n - 1 ) * M a / 6 0 * R / 1 0 0 0 * T 1 * [ ( p 2 / p 1 ) ^ ( ( n - 1 ) / n ) - 1 ] ;

/ / i n d i c a t e d p ow er i n kW23

24   P i s o = M a / 6 0 * R / 1 0 0 0 * T 1 * log ( p 2 / p 1 ) ;

/ / i s o t h e r m a l p ow er25   E T A i s o = P i s o / I P * 1 0 0 ;

/ / i s o t h e r m a le f f i c i e n c y

2627   E T A m e c h = I P / P s h a f t * 1 0 0 ;

/ / m e c h a n i c a le f f i c i e n c y

28

29   E T A o v r _ i s o = P i s o / P s h a f t * 1 0 0 ;

// o v e r a l l i s o t h e r ma le d d i c i e n c y

30

31   printf ( ’ ( i ) The a c t ua l V ol um et ri c e f f i c i e n c y i s : %2

. 2 f p e r c e n t .   \n ’, E T A v o l ) ;

32   printf ( ’ ( i i ) The I n d i c a t e d Power , I P i s : %1 . 3 f KW.\n ’ , I P ) ;

33   printf ( ’ ( i i i ) The I s o t h er m a l e f f i c i e n c y i s : %2 . 2 f  p e r c e n t .\ n ’ , E T A i s o ) ;

34   printf ( ’ ( i v ) The M ec ha ni ca l e f f i c i e n c y i s : %2 . 1 f  p e r c e n t .\ n ’ , E T A m e c h ) ;

35   printf ( ’ ( v ) The O ve ra l l i s o t h e r ma l e f f i c i e n c y i s :%2 . 1 f p e r c e n t . \ n ’ , E T A o v r _ i s o ) ;

Scilab code Exa 10.5  Example 5

1   // 5 (b ) i s a s f o l l o w s :

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2   clc

3   clear4   //DATA GIVEN5   m = 6 . 7 5 ;   // mass o f a i r i n kg / min6   p 1 = 1 ;   // p r e s s u r e i n b ar7   T 1 = 2 1 + 2 7 3 ;   / / temp . i n K8   p 2 = 1 . 3 5 ;   // p r e s s u r e i n b ar9   T 2 = 4 3 + 2 7 3 ;   / / temp . i n K

10   D T c w = 3 . 3 ;   // temp . r i s e o f c o o l i n gw a t e r i n deg . c e l s i u s

11   C p = 1 . 0 0 3 ;   //Cp f o r a i r i n kJ /kgK12   / / gamma f o r a i r = 1 .4

13   g = 1 . 4 ;14

15   W = m * C p * ( T 2 - T 1 ) ;   / / wo rk i n k J / min16   // I f t he c o mp r es s io n would ha ve b een i s o t r o p i c ,17   //T 2=T1∗( rp ) ˆ[ ( g−1)/g ]18   r p = p 2 / p 1 ;

19   T _ 2 = T 1 * ( r p ) ^ [ ( g - 1 ) / g ] ;

20   Q r = m * C p * ( T _ 2 - T 2 ) ;   // h ea t r e j e c t e d t o c o o l i n gw a t e r

21

22   M w = Q r / [ 4 . 1 8 * ( D T c w ) ] ;  // mass of c o o l i n g w at er i nkg/min

23

24   printf ( ’ ( i ) The Work i s : %3 . 2 f k J / mi n .   \n ’ , W ) ;

25   printf ( ’ ( i i ) The Mass o f c o o l i n g w at er i s : %1 . 2 f kg/ min .   \n ’ , M w ) ;

26

27   //NOTE:28   / / i n t he q u e s t i o n c o mp r es s io n p r o c e s s i s m en ti on ed

and p2 i s g i v en a s 0 . 3 5 ba r ( p2<p1 )29   / / whi ch i s wrong and f u r t h e r p2 i s g iv en a s 1 . 3 5 ba r

which i s a l l o w ab l e30   / / so h er e v al ue o f p2 i s t a ke n a s 1 . 3 5 ba r .

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Scilab code Exa 10.6  Example 6

1   clc

2   clear

3   //DATA GIVEN4   V 1 = 1 4 ;   // q u an t it y o f a i r t o

b e d e l i v e r e d , i n mˆ 3/ mim5   p 1 = 1 . 0 1 3 ;   // i n t a k e p r e s s ur e i n

b a r6   T 1 = 1 5 + 2 7 3 ;   / / i n t a k e t e m p e ra t u r e

i n K7   p 2 = 7 ;   // d e l i v e r y p r e s s u r e

i n b ar8   N = 3 0 0 ;   / / s p e ed o f  

c o m p r e ss o r i n R . P . M.9   n = 1 . 3 ;   / / c o m p r e s s i o n a nd

e x p an s i o n i n d ex10   R = 0 . 2 8 7 ;

11

12   / / c l e a r a n c e volume , Vc = 0 . 0 5 Vs , Vs=s we pt vo lu me13   // swept volume Vs=V1−V3=V1−Vc=V1−0.05Vs14   //V1=1.05Vs15   V p c = V 1 / N / 2 ;

// (V1−V4 ) vo lum e i n du c ed p e r c y c l e i n mˆ 3

16   //V4/V3=(p2/p1 ) ̂ ( 1/ n )17   c = ( p 2 / p 1 ) ^ ( 1 / n ) ;

18   //V4=c ∗V3=c ∗ 0 . 0 5 V s19   //V1−V4=1.05Vs−c ∗ 0 . 0 5 V s20   V s = V p c / ( 1 . 0 5 ) / ( 1 . 0 5 - c * 0 . 0 5 ) ;

/ / v o lu me s w ep t i n mˆ 321

22   / / u s i n g r e l a t i o n ( T2 /T1 ) =( p2 / p1 ) ˆ ( ( n−1)/n) ;23   T 2 = T 1 * ( p 2 / p 1 ) ^ ( ( n - 1 ) / n ) ;

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/ / d e l i v e r y temp .

T 2 i n K24

25   I P = ( n ) / ( n - 1 ) * p 1 * 1 0 ^ 5 * V p c / 1 0 0 * [ ( p 2 / p 1 ) ^ ( ( n - 1 ) / n ) - 1 ] ;

/ / i n d i c a t e d p ow er i n kW26

27   printf ( ’ ( i ) The Swept volume o f t he c y l i n d e r , Vs i s: %1 . 4 f mˆ 3 .   \n ’ , V s ) ;

28   printf ( ’ ( i i ) The d e l i v e r y t em p er a tu r e , Ts i s : %3 . 0 f  deg . c e l s i u s .   \n ’  , ( T2 - 2 7 3 ) ) ;

29   printf ( ’ ( i i i ) The I n d i c a t e d p ow er , I P i s : %2 . 2 f kW .\n ’ , I P ) ;

3031   //NOTE:32   / / t h e r e i s s l i g h t v a r i a t i o n i n a ns we r s i n t ex tb oo k

due t o r ou nd in g o f f o f v a l u es i n book

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Chapter 13

Transmission of Motion and

Power

Scilab code Exa 13.1  Example 1

1   clc

2   clear

3   //DATA GIVEN4   N 1 = 2 4 0 ;   // s pe ed o f t he e n g in e

s h a f t i n R . P .M.5   d 1 = 1 . 5 ;   // d i am et e r o f p u l l e y on

e ng i n e s h a f t i n m6   d 2 = 0 . 7 5 ;   // d i am et e r o f p u l l e y on

ma ch ine s h a f t i n m7   t = 0 . 0 0 5 ;   // t h i c k n e s s o f t h e b e l t

i n m8

9   // w it h no s l i p10   // (N2/N1) =(d1+t ) /( d2+t )

11   N 2 = ( d 1 + t ) / ( d 2 + t ) * N 1 ;   / / s p ee d o f t h e m ac hi nes h a f t i n R . P .M.12

13   // w i t h s l i p o f 2%14   S = 2 ;   // s l i p i n %

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15   // (N2/N1) =(d1+t ) /( d2+t ) ∗((100−S ) / 1 0 0 )

16   N 2 s = ( d 1 + t ) / ( d 2 + t ) * N 1 * ( ( 1 0 0 - S ) / 1 0 0 ) ;17

18   printf ( ’ ( i ) The S pe ed o f m ac hi ne s h a f t , N2 w it h nos l i p i s : %4 . 1 f R . P .M.   \n ’ , N 2 ) ;

19   printf ( ’ ( i i ) The S pe ed o f m ac hi ne s h a f t , N2 w it hs l i p o f 2 p e rc e n t i s : %4 . 1 f R .P .M.   \n ’ , N 2 s ) ;

Scilab code Exa 13.2  Example 2

1   clc

2   clear

3   //DATA GIVEN4   r 1 = 9 0 0 / 2 0 0 0 ;   // r a di u s o f l a r g e r

p u l l ey i n m5   r 2 = 3 0 0 / 2 0 0 0 ;   // r a d i us o f s m a l l e r

p u l l ey i n m6   d = 6 ;   / / d i s t a n c e b et we en t h e

c e n t r e s o f p u l l e y i n m7

8   / / L e n gt h o f c r o s s b e l t , L c r o s s =( p i ) ( r 1+r 2 ) +( r 1 +r 2 )ˆ2 / d+2d ;

9   L c r o s s = ( % p i ) * ( r 1 + r 2 ) + ( r 1 + r 2 ) ^ 2 / d + 2 d ;

10   / / L e n g t h o f o p en b e l t , L op en =( p i ) ( r 1 +r 2 ) +( r 2−r1 ) ̂ 2/ d+2d ;

11   L o p e n = ( % p i ) * ( r 1 + r 2 ) + ( r 2 - r 1 ) ^ 2 / d + 2 d ;

12

13   L r e d = L c r o s s - L o p e n ;   / / l e n g t h t o be r e du c ed14   printf ( ’ The L en gth o f t he b e l t t o be r ed uc ed ,   \n (

t o c h an g e t h e d i r e c t i o n o f r o t a t i o n o f t h ef o l l o w e r p u l l e y s ) i s : %2 . 0 f mm.   \n ’ , ( L r ed * 1 0 0 0 ) ) ;

Scilab code Exa 13.3  Example 3

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1   clc

2   clear3   //DATA GIVEN4   T 1 = 1 5 0 0 ;   // t e n s i o n on t he t i g h t

s i d e i n N5   T 2 = 1 2 0 0 ;   // t e n s i o n on t he s l a c k

s i d e i n N6   v = 8 0 ;   // s pe e d o f t h e b e l t i n m

/ s7

8   P = ( T 1 - T 2 ) * v ;   / / po wer t r a n s m i t t e d byt h e b e l t i n w a tt s

910   printf ( ’ The Power t r a n s mi t t ed by t he b e l t i s : %2 . 0 f  

kW.   \n ’  , ( P / 1 0 0 0 ) ) ;

Scilab code Exa 13.4  Example 4

1   clc

2   clear

3   //DATA GIVEN4   v = 5 0 0 ;   // s pe e d o f t h e b e l t i n m

/min5   m u = 0 . 3 ;   // c o e f f i c i e n t o f 

f r i c t i o n6   t h e t a = 1 6 0 ;   // a n gl e o f c o nt a ct i n

d e g r e e s7   T 1 = 7 0 0 ;   / /maximum t e n s i o n i n t h e

b e l t i n N8

9   // (T1/T2)=e ̂ (mu∗ t h e t a )10   t h e t a = t h e t a * ( % p i ) / 1 8 0 ;   // t h e ta c o nv e rt e d i n t or a d i a n s

11   T 2 = T 1 / ( % e ^ ( m u * t h e t a ) ) ;   // t e n s i o n on t he s l a c ks i d e i n N

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12   v = v / 6 0 ;   // s pe ed o f t he b e l t

c o n v er t e d i n t o m/ s13   P = ( T 1 - T 2 ) * v ;   / / po wer t r a n s m i t t e d byt h e b e l t i n w a tt s

14

15   printf ( ’ The Power t r a n s mi t t ed by t he b e l t i s : %2 . 3 f  kW.   \n ’  , ( P / 1 0 0 0 ) ) ;

Scilab code Exa 13.5  Example 5

1   clc

2   clear

3   //DATA GIVEN4   r 1 = 7 5 0 / 2 0 0 0 ;   // r a di u s o f l a r g e r

p u l l ey i n m5   r 2 = 3 0 0 / 2 0 0 0 ;   // r a d i us o f s m a l l e r

p u l l ey i n m6   d = 1 . 5 ;   / / d i s t a n c e b et we en t h e

c e n t r e s o f p u l l e y i n m7   T m s = 1 4 ;   / /maximum s a f e t e n s i o n

i n N/mm8   b = 1 5 0 ;   // w i dt h o f t h e b e l t i n

mm9   v = 5 4 0 ;   // s pe e d o f t h e b e l t i n m

/min10   m u = 0 . 2 5 ;   // c o e f f i c i e n t o f 

f r i c t i o n11

12   T 1 = T m s * b ;   / /maximum t e n s i o n i n t h eb e l t i n N

13   v = v / 6 0 ;   // s pe ed o f t he b e l tc o n v er t e d i n t o m/ s14   // ( i ) f o r open b e l t15   A L P H A o = asin   ( ( r 1 - r 2 ) / d ) * 1 8 0 / ( % p i ) ;   / / a l p h a i n

d e g r e e s

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16   T H E T A o = 1 8 0 - 2 * A L P H A o ;   // a n g l e o f  

l ap o r c on t a c t i n deg17   T 2 o = T 1 / ( % e ^ ( m u * ( T H E T A o * % p i / 1 8 0 ) ) ) ;   // t e n s i o n ont h e s l a c k s i d e i n N

18   P o = ( T 1 - T 2 o ) * v ;   //pow e rt r an s mi t te d by t he b e l t i n w at ts

19

20   // ( i i ) f o r c r o s s b e l t21   A L P H A c = asin   ( ( r 1 + r 2 ) / d ) * 1 8 0 / ( % p i ) ;   / / a l p h a i n

d e g r e e s22   T H E T A c = 1 8 0 + 2 * A L P H A c ;   // a n g l e o f  

l ap o r c on t a c t i n deg

23   T 2 c = T 1 / ( % e ^ ( m u * ( T H E T A c * % p i / 1 8 0 ) ) ) ;   // t e n s i o n ont h e s l a c k s i d e i n N

24   P c = ( T 1 - T 2 c ) * v ;   //pow e rt r an s mi t te d by t he b e l t i n w at ts

25

26   printf ( ’ ( i ) The Maximum P ow er t r a n s m i t t e d by t h eo pe n b e l t i s : %2 . 3 f kW.   \n ’  , ( P o / 1 0 0 0 ) ) ;

27   printf ( ’ ( i i ) The Maximum P ower t r a n s m i t t e d by t h ec r o s s b e l t i s : %2 . 3 f kW.   \n ’  , ( P c / 1 0 0 0 ) ) ;

Scilab code Exa 13.6  Example 6

1   clc

2   clear

3   //DATA GIVEN4   b = 0 . 2 5 ;   // w i dt h o f t h e b e l t i n m5   t = 0 . 0 0 6 ;   // t h i c k n e s s o f t h e b e l t

i n m

6   r = 9 0 0 / 2 0 0 0 ;   // r a d i us o f t he p u l l e yi n m7   r h o = 1 1 0 0 ;   // d e n s i t y o f t he

m a t e r i a l i n kg /mˆ 38   T p = 2 ;   // p e r m i s s i b l e t e n s i o n o f  

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t h e b e l t i n MN/mˆ 2

9   r a t i o = 2 ;   / / r a t i o o f T1 /T2=210   N = 2 0 0 ;   // s pe ed o f t he p u l l e y i nR.P.M.

11

12   T m a x = T p * 1 0 ^ 6 * b * t ;   / /maximum s a f e t e n s i o no f t h e b e l t

13   / / c e n t r i f u g a l t e n s i o n , Tc=m∗v ˆ214   m = ( b * t ) * 1 * r h o ;   // mass o f t he b e l t p er

u n i t m et re l e n g th15   v = 2 * ( % p i ) * ( r + t / 2 ) * N / 6 0 ;

16   T c = m * v ^ 2 ;

1718   T 1 = T m a x - T c ;   // t e n s i o n i n t he t i g h t

s i d e i n N19   T 2 = T 1 / r a t i o ;   // t e n s i o n i n t he s l a c k

s i d e i n N20   P = ( T 1 - T 2 ) * v ;   / / po wer t r a n s m i t t e d by

t h e b e l t i n w a tt s21

22

23   printf ( ’ ( i ) The C e n t r i f u g a l t e n s i o n Tc i s : %3 . 1 f N .

\n ’, T c ) ;

24   printf ( ’ ( i i ) The Power t r a n s mi t t e d by t he b e l t i s :%2. 1 f kW.   \n ’  , ( P / 1 0 0 0 ) ) ;

Scilab code Exa 13.7  Example 7

1   clc

2   clear

3   //DATA GIVEN4   P = 3 5 ;   // p ower r e q u i r e d t o bet r an s mi t te d by t he b e l t i n kW

5   d = 1 . 5 ;   // e f f e c t i v e d ia me te r o f  p u l l ey i n m

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6   N = 3 0 0 ;   // s pe ed o f t he p u l l e y i n

R.P.M.7   t h e t a = 1 1 / 2 4 * 2 * % p i ;   // a n gl e o f c o nt a ct i nr a d i a n s

8   m u = 0 . 3 ;   // c o e f f i c i e n t o f f r i c t i o n

9   t = 0 . 0 0 9 5 ;   // t h i c k n e s s o f t h e b e l ti n m

10   r h o = 1 1 0 0 ;   // d e n s i t y o f t hem a t e r i a l i n kg /mˆ 3

11   s i g m a = 2 . 5 ;   // p e r m i s s i b l e s t r e s s i nMN/mˆ2

1213   v = % p i * d * N / 6 0 ;   // s pe e d o f t h e b e l t i n m

/ s14   //P=(T2−T1 ) ∗v , s o ( T2−T1)=P/v . . . . . . . . . . . . . . . . . . . . ( 1 )15   c = % e ^ ( m u * t h e t a ) ;   // so , T2/T1=c . . . . . . . . ( 2 )16   //By e q ua t i on ( 1 ) and ( 2 ) ,17   T 2 = ( P / v * 1 0 0 0 ) / ( c - 1 ) ;   // t e n s i o n i n t he s l a c k

s i d e i n N18   T 1 = c * T 2 ;   // t e n s i o n i n t he t i g h t

s i d e i n N19

20   //maximum te ns i o n , Tmax=sigma ∗b∗ t =0.23 75∗b∗1 0 ˆ 6 N( 3 )

21   / / c e n t r i f u g a l t e n s i o n , Tc=m∗v ˆ 2 = 5 8 0 0 . 5∗b N( 4 )

22   //T1=Tmax−c( 5 )

23   / /By eq n . ( 3 ) , ( 4 ) and ( 5 )24   b = T 1 / ( ( s i g m a * 1 0 ^ 6 * t ) - ( t * 1 * r h o * v ^ 2 ) ) ;   // w i dt h o f  

t h e b e l t i n m25

26   printf ( ’ The Width o f t h e b e l t i s : %3 . 0 f mm ( s ay 1 50mm) .   \n ’ , ( b * 1 0 0 0 ) ) ;

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Scilab code Exa 13.9  Example 9

1   clc

2   clear

3   //DATA GIVEN4   T o = 1 0 0 0 ;   / / i n i t i a l t e n s i o n i n t h e

b e l t i n N5   t h e t a = 1 5 0 ;   / / a n g l e o f e mb ra ce i n

d e g r e e s6   m u = 0 . 2 5 ;   // c o e f f i c i e n t o f 

f r i c t i o n7   v = 5 0 0 ;   // s pe e d o f t h e b e l t i n m

/min8

9   // I n i t i a l te ns i on , To=(T1+T2) /210   // so , (T1+T2 ) = 2 0 0 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ( 1 )11   t h e t a = t h e t a * ( % p i ) / 1 8 0 ;   // t h e ta c o nv e rt e d i n t o

r a d i a n s12   c = % e ^ ( m u * t h e t a ) ;   // so , T2/T1=c . . . . . . . . ( 2 )

13   //By e q ua t i on ( 1 ) and ( 2 ) ,14   T 2 = ( T o * 2 ) / ( c + 1 ) ;   // t e n s i o n i n t he s l a c k

s i d e i n N15   T 1 = c * T 2 ;   // t e n s i o n i n t he t i g h t

s i d e i n N16

17   v = v / 6 0 ;   // s pe ed o f t he b e l tc o n v er t e d i n t o m/ s

18   P = ( T 1 - T 2 ) * v ;   / / po wer t r a n s m i t t e d byt h e b e l t i n w a tt s

19

20   printf ( ’ ( i ) The T e ns io n i n t he t i g h t s i d e T1 i s : %4. 0 f N .   \n ’ , T 1 ) ;

21   printf ( ’ The T e n s i o n i n t h e s l a c k s i d e T2 i s :%3 . 1 f N .   \n ’ , T 2 ) ;

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22   printf ( ’ ( i i ) The Power t r a n s mi t t e d by t he b e l t i s :

%2. 2 f kW.   \n ’  , ( P / 1 0 0 0 ) ) ;

Scilab code Exa 13.10  Example 10

1   clc

2   clear

3   //DATA GIVEN4   P = 4 0 0 ;   / /maximum v a l u e o f f o r c e

t ha t can be d ev el op ed i n N5   m u = 0 . 2 5 ;   // c o e f f i c i e n t o f 

f r i c t i o n6   d = 0 . 6 ;   / / d i a m et e r o f drum i n m7   // R e fe r t he f i g u r e8   t h e t a = 1 8 0 + 4 5 ;   // a n gl e o f c o nt a ct i n

d e g r e e s9   t h e t a = t h e t a * ( % p i ) / 1 8 0 ;   // t h e ta c o nv e rt e d i n t o

r a d i a n s10

11   //moments about A , Ma= 0,

12   T 1 = P * 1 / 0 . 5 ;13

14   // ( i ) Drum i s r o t a t i n g a n t i c l o c k w i s e15   //T1>T2 ( T1/T2 )=e ̂ (mu∗ t h e t a )16   T 2 = T 1 / ( % e ^ ( m u * t h e t a ) ) ;

17   M c a c = ( T 1 - T 2 ) * ( d / 2 ) ;   //maximum br ak in gt o r q u et h at can be d ev el op ed i n N

18

19   // ( i ) Drum i s r o t a t i n g c l o c k w i s e20   //T2>T1 ( T2/T1 )=e ̂ (mu∗ t h e t a )

21   T 2 = T 1 * ( % e ^ ( m u * t h e t a ) ) ;22   M c c = ( T 2 - T 1 ) * ( d / 2 ) ;   //maximum br ak in gt o r q u et h at can be d ev el op ed i n N

23

24   printf ( ’ ( i ) The Maximum b r a k i n g t o r q u e t h a t c an b e

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d ev el op ed i n a n t i c l o c k w i s e d i r e c t i o n i s : %3 . 0 f Nm

.   \n ’ , M c a c ) ;25   printf ( ’ ( i i ) The Maximum b r a k i n g t o r q u e t h a t c an b ed e ve l op e d i n c l o c k w i s e d i r e c t i o n i s : %3 . 1 f Nm.   \

n ’ , M c c ) ;

Scilab code Exa 13.11  Example 11

1   clc

2   clear3   //DATA GIVEN4   P t = 8 0 ;   / / po wer t o be

t r a n s mi t t e d by t he r op e i n kW5   d = 1 . 5 ;   // d ia me te r o f p u l l e y i n

m6   N = 2 0 0 ;   // s pe ed o f t he p u l l e y i n

R.P.M.7   a l p h a = 4 5 / 2 ;   // s emi a n gl e o f g ro ov e

i n d e gr e e s8   t h e t a = 1 6 0 ;   // a n gl e o f c o nt a ct i n

d e g r e e s9   m u = 0 . 3 ;   // c o e f f i c i e n t o f 

f r i c t i o n10   m = 0 . 6 ;   // mass o f e ac h r op e p er

u n i t m et re l e n g th11   T s = 8 0 0 ;   // s a f e p u l l i n N12

13   / / c e n t r i f u g a l t e n s i o n , Tc=m∗v ˆ214   v = ( % p i ) * d * N / 6 0 ;   / / v e l o c i t y

o f t he r op e i n m/ s

15   T c = m * v ^ 2 ;16

17   T 1 = T s - T c ;   // t e n s i o n i nt h e t i g h t s i d e i n N

18   // (T1/T2)=e ̂ (mu∗ t h e t a )

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19   t h e t a = t h e t a * ( % p i ) / 1 8 0 ;   / / t h e t a

c on v e rt e d i n t o r a di a n s20   a l p h a = a l p h a * ( % p i ) / 1 8 0 ;   // al p hac on v e rt e d i n t o r a di a n s

21   T 2 = T 1 / ( % e ^ ( m u * t h e t a / sin ( a l p h a ) ) ) ;   / / t e n s i o n ont h e s l a c k s i d e i n N

22   p = ( T 1 - T 2 ) * v ;   //pow e rt r an s mi t te d by t he b e l t i n w at ts

23

24   / / no . o f r o p e s r e q u i r e d , n=T o ta l po wer t r a n s m i t t e d /Power t r a n s m i t t e d by e ac h r o pe

25   n = P t / ( p / 1 0 0 0 ) ;

2627   // I n i t i a l t en s i o n in rope , To=(T1+T2+2Tc) /228   T o = ( T 1 + T 2 + 2 * T c ) / 2 ;

29

30   printf ( ’ ( i ) The Number o f r o p es r e q u i r e d f o r t hed r i v e s i s : %1 . 1 f s a y %1 . 0 f .   \n ’ , n , n ) ;

31   printf ( ’ ( i i ) The I n i t i a l t e n s i o n i n t h e r op e , To i s: %3 . 2 f N .   \n ’ , T o ) ;

Scilab code Exa 13.12  Example 12

1   clc

2   clear

3   //DATA GIVEN4   T = 7 2 ;   / / number o f t e e t h5   P c = 2 6 ;   // c i r c u l a r p i t ch i n mm6

7   / / c i r c u l a r p i t ch , Pc=( p i ∗D)/T

8   D = P c * T / ( % p i ) ;   // p i t c h d i am et e r i n m9   //Pc∗Pd=(p i )10   P d = ( % p i ) / P c ;   // d i a m et r a l p i t c h i n

t e e t h /mm11   // Module , m=D/T

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12   m = D / T ;   / / m o d ul e i n mm/ t o o t h

1314   printf ( ’ ( i ) The P i t c h d ia me te rm , D i s : %3 . 2 f mm.   \n

’ , D ) ;

15   printf ( ’ ( i i ) The D i a me t ra l p i t ch , Pd i s : %1 . 2 f  t e e t h /mm.   \n ’ , P d ) ;

16   printf (  ’ ( i i i ) The M odul e , m i s : %1. 2 f mm/ t o ot h .   \n ’ ,m

) ;

Scilab code Exa 13.13  Example 13

1   clc

2   clear

3   //DATA GIVEN4   T a = 4 0 ;   // number o f t e e t h o f  

g e a r A5   T b = 1 0 0 ;   // number o f t e e t h o f  

g e a r B6   T c = 5 0 ;   // number o f t e e t h o f  

g e a r C

7   T d = 1 5 0 ;   // number o f t e e t h o f  g e a r D

8   T e = 5 2 ;   // number o f t e e t h o f  g e a r E

9   T f = 1 3 0 ;   // number o f t e e t h o f  g e a r F

10   N a = 1 0 0 0 ;   / / s p ee d o f t h e mo to rs h a f t i n R . P .M.

11

12   //(Nf/Na)=(Ta/Tb) ∗ (Tc/Td) ∗ ( T e / T f )

13   N f = ( T a / T b ) * ( T c / T d ) * ( T e / T f ) * N a ;   // S peed o f t heo ut pu t s h a f t i n R . P .M.14

15   printf ( ’ The S peed o f t he o ut pu t s h a ft , Nf i s : %3 . 2 f  R.P.M.   \n ’ , N f ) ;

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