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  • 8/10/2019 2nd-1st sem-2011Q

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    ExlCh.Eff/21411l1201l1SPL

    BACHELOR OF CHEMICAL ENGINEERING EXAMINATION,2011

    ( 2nd Year, 1st Semester)

    MECHANICS OF FLUIDS

    Time: Three hours Full Marks: 100

    ( 50 marks for each Part )

    Use separate answer scripts for each Part

    RT

    -

    I

    Answer Question No 1 and any two from the rest

    Assume any missing data

    1. a) A velocity field is defined as

    V=

    3yi

    - 6x]

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    . J ::

    [2J

    2.

    a)

    -.

    Patm

    Fig 1

    The Lid) ratio for both the branch o-a) and o-b) refer to

    Fig 1) are 100. The Leq/d) ratio for a globe valve is 340 and

    that of a gate valve is 8. The diameters of two branches are

    same. Find the ratio offlow rates through line -a) and line

    o-b) considering the Fanning friction factor to be invariant

    of Reynolds. number fuUy rough zone). 5

    b) Consider expansion of

    multiple

    n number of tubes each of

    diameter do) into a header of diameter D Refer to Fig 2

    or

    turbulent

    flow

    0 Derive an expressionror pressure differentialP,-P2

    i

    h) Derivetheexpressionor mClionalloss,h

    I

    Consider that at section I the pressure is uniform across the

    ross section

    [ 3 ]

    3.

    a) You are an engineer for a company and are to select an

    appropriate fluid meter from your waterhouse stock to

    measure the water flow rate in a 6 inch nominal diameter)

    schedule 40, horizontal commercial steel pipe. The fluid

    meter is needed immediately, so no time is available for

    machining or modification. The flow rate is estimated to be

    3 3

    between 0.0065 m /s and 0.-025m Is. A mercury manometer

    is to be used to measure the appropriate pressure difference

    to determine the flow rate.

    Your instructions are to choose a fluid meter to determine

    the flow rate with a maximum uncertainity of 10

    percentage error) because of errors in reading in

    manometer. You estimate that the manometer can be read

    with an uncertainity absoluteerror) of 0.15 cm.

    Net pressure drop across the meter must not exceed 7 kPa.

    The following meters are available

    Type of flow meter

    Venturi

    Throat / orifice diameter

    4.5 in

    Thin-plate orifice

    2.5 in

    Consider that the dischargecoefficient of venturimeterand

    orificemeter are 0.94 and 0.61, respectively. The inside

    diameter for a 6 inch Schedule40 commercialsteel pipe is

    6.065 i:lch.

    u ;

    lL

    i

    f

    A

    do

    f

    1

    1

    ID

    ,

    f

    ]I

    I

    Y

    Fig

    2

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    [4J

    4.

    b) Explain the working principle of a rotameter. Why is itcalled

    as an area meter ? 12+4

    Water (at 25C, p =1000 kg/m3, /l = Icp) flows from a large

    reservoir (zl = SSm) to a storage tank (z2 = 5m), as shown in

    Fig.2. The pipe entrance at B is well rounded. The pipeline from

    B to C contains 4 gate valves, three standard 90 elbows and

    one tee with flow through the main run. The pipe line

    trom

    D to

    E contains four gate valves, six 90 standard elbows, two 45

    standard elbows, one tee with flow through the main run and a

    venturi meter. The venturimeter is installed to measure the flow

    rate. The reading of the manometer (manometric fluid mercury,

    p

    =

    13600 kg/m ) connected between the upstream and the

    throat of the venturimeteris 75cm. The pipe line is 300 m long

    I

    and is a 2 inch Schedule 40 (inside diameter 2.067 inch) steel

    pipe. The loss coefficient (k) data for commercial(2 inch) pipe

    fittingaregiven below:

    Gatevalve

    90 standardElbow

    0.16

    0.95

    Tee, line flow

    0.90

    The discharge coefficient of venturimeter, Cv = 0.98.

    Calculate (i) the

    ow

    rate through the pipeline, (ii) the power

    input to thepumpfor theoverallefficiencyof 85 .(iii)pressure

    [ 5 ]

    ~

    ~~7~ y]

    Fig.

    5. A catalyst having spherical particles of Dp= 50 microns and

    Ps=1.65g/cm3is to be usedto contact a hydrocarbonvapor in a

    fluidized reactor at 480C and I atm pressure. At rest the bed

    has a porosity of 0.35 and a height of 1m. At operating

    conditions, the fluid viscosity is 0.02 cp and its density is 3.4

    kg/m3.The porosityat minimumfluidizationvelocity is 0.42.

    a) Determine

    i) the superficialgas velocitynecessaryto fluidize the bed

    ii) the velocityat which the bed would begin to flowwith

    the gas

    ill) the extent of bed expansion when the gas velocity is

    averageof velocitiespreviouslydetermined.

    b) Does aggregative/ particulatefluidizationoccur?

    The ErgunEquationfor flow through packedbed is as follows:

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    [6 ]

    RT

    -

    II

    Answer

    any three

    questions.

    All questions carry equal marks.

    2 marks reserved for neat and well organized answer script.

    Assume any missing data.

    6. a) Find the dimensionality and diu:ctionality

    for

    the velocity

    field given by V =axi + bX2j::..~xtlc (a, b, c are constants).

    2

    b) Consider a flow field given by V = Ai + btj, A = 2m/s,

    B=0.3m/s2.Find the equation of pathline followed by the

    particle located at (x, y = (1, 1) at the instant t = O. 4

    c) A steady, incompressible flow is given byV =Axi

    -Ayj; with

    A = 2s-I. Determine the stream function that will yield this

    velocityfield. 4

    d) The velocity profile for an incompressible fluid at the

    entranceto a pipe is flatas shown inFig.6.At section2 it is

    parabolic and is given byV = Vm(1-r21R2).

    Obtain the drag

    force

    F acting on the fluid in terms of the

    pressure PI' P2' density p, Voand R. 6

    [ 7 ]

    7. Heavy oil having a specific gravity of 0.85 and an absolute

    viscosity of 4x 10-2N.s/m2 is pumped through 20m ofO.052m

    inside diameterPVCpipe(zerorelative roughness).Thepipeline

    is shown in Fig.7and containsonecheckvalve,two gate valves,

    four 45 standard elbowsand a nozzlewith a throat diameter of

    0.026m. A manometer connecting the inlet and throat of the

    nozzle reads 2.0m of mercury (specific gravity of 13.6). Find

    the pressure loss between points 2 and 3. Neglect loss in the

    nozzle.

    Draw the nature of the Energy grade line and hydraulic grade

    line.

    Fitting

    Checkvalve

    Gatevalve

    45 standard elbow

    Loss coefficient

    2.1

    0.16

    0.30

    13+3

    q.(j. ~L

    ~

    - --

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    [ 8 ]

    8.

    a) Petroleum oil of specific gravity 0.9 flows through a

    horizontalpipe. A pitot tube is inserted at the center of the

    pipe and its leads are filledwith the sameoil and attachedto

    a U tube containingwater.Thereading of the manometeris

    90 cm. Find the velocity at the center o f the pipe. 4

    b) In fully rough zone friction factor is invariant of Reynold s

    number justify with reasons. 3

    c) Water is in turbulent flow through at 50 mm J.D. tube. The

    pressure drop is 1.57 kN/mo per meter of tube. Calculate the

    thickness oflaminar sublayer and buffer layer. Find the eddy

    viscosity. Assume water viscosity as IO-3kglm.s.

    The universal velocity distribution is given as follows

    u+ =y+; O;s;y+;s; 5;u+ =-3.05+5Iny+; 5;s;y+ ;S;30

    u+

    =

    5.5 + 2.5In y+; y+ ~30

    d) Cd vs. N Re,pcurve for flow around a sphere shows an

    abrupt decrease in drag coefficientat Re=3x 105. 2

    9.

    a) Draw the shear stress vs. deformation rate curve for

    Binghamplasticandpseudoplasticfluid. 2

    b) A water jet pump has jet area 0.01m2 and jet speed 20m/s.

    The jet is within a secondary stream of water having speed

    Vs=2m/s. The total area of the duct (the sum of the jet anl1

    2 .

    [ 9 ]

    stream. The pressures of the jet and the secondary stream

    are the same at the pump inlet. Determine the speed at the

    pump exit and the pressure rise P2- Pl IO

    V

    2 W\1 s

    = ~Js

    --Q,) V)

    O

    cl.. :.o

    t:W

    - V) .Q

    - :::

    0

    cv -

    cJ ) Co.>

    QJ (1) f O

    -- 0. 0

    0

    4

    I

    . . .

    .

    . .

    .

    c: CLJ

    C1J

    - -

    c:: 0 ::J

    ~

    V )

    E c: to

    ~ .~ E 0.2

    1

    ........

    C. ~

    ....

    -

    1.0

    ..

    ..

    .

    ..-=-l

    . .

    . .

    . . . . . .

    . . . .

    ~.

    .

    . ~~. i

    . . .

    . .

    .

    0

    0

    .

    0.2 04 0.6 0.8

    1 0

  • 8/10/2019 2nd-1st sem-2011Q

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    0.015

    0.01

    103

    2(1o } 3 4 5 6 S 10.

    2(104} 3 4 5 6 8 105

    0.00001

    -.- -- 6-e1oe

    7 -21107} 3-4_5 ,-,--

    10

    ~

    - Qonn,,-

    E D - VU()5

    --..

    f)

    ..

    Q oooo

    Reynolds number

    R

    =v

    Figure 7.9

    The Moody chart for friction factor from [3] .

    0,1

    0.09

    0.08

    0.07

    0.06

    0.05

    0.04

    ....

    ....

    0

    0.03

    U

    2

    c

    0

    ....

    0.025

    ;::;

    ro

    Q)

    0::

  • 8/10/2019 2nd-1st sem-2011Q

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    F Pipe diameter in feet D

    0.5

    8

    1

    .2 0.3 0.4

    I

    0.6 O.

    ,.,

    0.01

    0.008

    0.006

    0.005

    0.004

    0.003

    ,..,.

    0.06

    0.03

    0.02 I.~

    0.05

    0.04

    .0.035

    0.03

    0.025

    0.002

    VI

    Q)

    0.

    0.

    s

    0.02 g

    0

    ...

    Ie

    I/)

    I/)

    (1)

    c:

    .c.

    0 >

    ;:,

    0

    ~

    Q)

    >

    +=I

    Q)

    ex:.

    0.001

    0.0008

    0.0006

    0.0005

    0.0004

    0.0003

    0.018 ~

    c:

    ~

    ;:,

    0.016 -e

    ;:,

    ....

    Q)

    ....

    Q)

  • 8/10/2019 2nd-1st sem-2011Q

    9/23

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    .

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    .Relativeroughness. ;

    ~ 8IINTEftNALINCOMPRESSIBlEViSCOuS FlDN

    0.0001

    0.000.08

    0.000.06

    0.000;05

    0.000.04

    0,000,03

    0.000.02

    0.000.01

    0.000,0008

    0.000,0006

    0.000,0005

    FIg.8.15

    50 80 150 300 500 800 1500 3000 SOOO

    40 60 100 200 400 600 1000. 2QOO 400Ci'

    Pipe diameter.p (millimeters)

    Relative roughness for pipes of common engineering . mater ials . (Data

    from~ usedPx..p .mILSJion

    .

    30

    .

    0 0

    is

    0

    0

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  • 8/10/2019 2nd-1st sem-2011Q

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  • 8/10/2019 2nd-1st sem-2011Q

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    [ 2 ]

    .

    6. a)A bracketis fixed to the wall by means of 4 identicalbolts and loadedby a vertical load as shown in.-

    Fig. 6a. Material of bolts is C30 C.S (Gy=340

    N mm2

    and factor of safety is 3. Determine the nominal

    diameterof the bolts. 10

    b) A bracketis supported by means of 4 rivets of samesize, as shown in Fig. 6b. Determinethe diameterof

    the rivet if the maximumpermissible shear stress.is 140MPa. 10

    1~

    i

    SQO

    f~

    7S

    T

    ~..

    Fig. 6a

    600

    ~

    40kN

    20kN

    80

    ~

    4-

    t

    ~

    f -

    I

    1

    ,;

    /

    Fig. 6b

    7. a) Why is the cross-sectionof the flat belt pulley armelliptical? The major axis of an ellipticalpulley arm

    placed inthe pl~e of rotation -Justify the statement. 2+6

  • 8/10/2019 2nd-1st sem-2011Q

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    ~ ~, Qj

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    @

    ExlCh.E/Math/T/21~/1l/20IiSPL

    BACHELOROF CHEMICALENGINEERINGEXAMINATION,011

    2nd Year, 1st Semester

    MAmEMATICS

    -

    Time: Three hours

    Full Marks: 100

    Answer any six questions.

    [ Four marks reserved for general proficiency]

    I. a Find the necessary and sufficient condition for the ordinary

    differential equation M x,y dx +N x,y dy =0 to be exact.

    8

    b Solvethe differentialequation

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    [ 2 ]

    b) Show that d~[ x-oJo (x)J ==-X-oJo+I(X).

    c) Show that J _1 (x)

    ==

    cosx .

    2

    4.

    a) DefineLegandredifferentialequation. Provethat

    Po(x)==~~

    (

    2-

    1)

    0

    ill

    20 dx x

    b) Prove that xP~(x) ==

    P~-I

    (x) + nPo(x) .

    c) Prove that Po(I)

    == I.

    ao 2

    5.

    a) Show that fe-x Hm(x)Ho(x)dx==O, m:;t:n

    -ao

    ==2ill~, m ==n

    {

    xt

    }

    exp --

    ao

    b) Prove that

    . ~-t == LLn(x)to.

    0=0

    c) Show that L2 (x) ==

    ~ (

    x2

    - 4x+2).

    fl [;2

    6. a) Solve ~

    ==X2

    -t

    using method of separation {)f

    at

    variables.Given that y(x,O)==f(x),

    Zl o

    ==g(x).

    [ 3 ]

    4

    b) If a string of length I is released from rest in the position

    y

    == 4A.x (~

    - x) . Show that the motion is described by the

    I

    4

    equation

    y(

    x t

    )

    - 321..~ 1 . (2n+1)1tX (2n+1

    )

    1tat

    , - 3.J 3sm cos

    7r 0=0

    (2n+I) I I 8

    2+6

    6

    ~ 2 U

    .

    7.

    a) Solve at

    ==

    a 2 for 0 0 gIven that

    2

    Ux(0, t) ==Ux(1t,t ) ==0 and u (x,0) ==sin x .

    8

    b) Solve a2~ + a2~ ==0, which also satisfies the following

    Ox Oy

    boundary conditions u(O,y) ==

    u l,y

    ==u(x,O) ==0 and

    8

    u( x,a) ==sin n1tX

    I

    .

    8

    ()

    8. a) A periodicfunctionof period 4 isdefined as

    f(x)=lxl

    -2

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    [ 4 ]

    9. a) State D Alambert s ratio test for convergence of infinite

    series. 2

    b) Test the following series for convergence

    1 x3 1.3 x5 1.3.5x7

    x+--+--+--+...

    2 3 2.4 5 2.4.6 7

    6

    c) Test for the convergence of the series

    i)

    1 1 I

    -+-+-+...

    1.22 2.32 3.42

    co

    ii)

    . .

    n=lnn

    8

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    ~

    ~y~

    D

    0r.t L

    C.w- ~)

    ExlCh.E/Chem.lT /212/10/20 1

    ~SP\..

    BACHEWR OF CHEMICALENGINEERINGEXAMINATION,011

    ( 2nd Year, 1st Semester)

    PHYSICAL CHEMISTRY

    Time: Three hours

    Full Marks: 100

    Use a separate Answer-Script for each part.

    ( 50 marks for each part )

    PART

    -

    I

    1. a) Define an ideal black body and give an example that

    approximatelyrepresents it.Describe Stefan-Boltzmannlaw

    of black body radiation. Show how it is consistent with the

    Planck s distribution of frequency (v) dependent energy

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    [ 2 ]

    2.

    a) Describe a Hermitian operator and show that the eigen

    functions of a hermitian operator having different eigen

    values are orthogonal.

    b) Evaluatethecommutator,[H,x], whereH isthe Hamiltonian

    operator for a free particle.

    c) State the Heisenberg s uncertainty principle. Find the

    uncertainty in speed of an electron located within an atom

    with positionaluncertaintyof 50 pm.

    d) What is the probability of the I-s electron of a hydrogen

    atom to be found in a spherical shell of radius r and r +dr

    around the nucleus? Also find the most probable radial

    distance of the I-s electron fromthe nucleus.Given, the I-s

    orbital wavefunction of the hydrogen atom,

    (

    1 r

    112--

    l l-s (r) = J;c aJ .e ao ; (ao- Bohr radius).

    3+3+5+6

    3.

    a) Define absorbance. Provide suitable justification for the

    Lambert-Beer s law and state the reasons for the

    photochemicalsystemsshowing deviations from it.

    b) An electron is confined to a molecule of length 1.0 nm.

    Consideringtheparticlein a boxmodel,find(a) itsminimum

    energy and (b) the minimum excitation energy for the

    electron from its lowest energy state.

    c) Using rigid rotor model for studyingrctational motion of a

    diatomic molecule, explain the equally spaced microwave

    [ 3 ]

    spectral lines observed experimentally and mention its

    usefulness.

    d) The force constant of the bromine molecule C~r 79Br)is

    240Nm-l. Calculate the fundamentalvibrational frequency

    and the zero point energy of the molecule. 5+5+4+3

    P RT II

    4.

    a) How does viscosity of a liquid change with change of

    temperature? 3

    b) How can you determine the molecular weightof a polymer

    molecule by measuring viscosity? 4

    c) How does the vapour pressure of a liquid vary with

    temperature?

    3

    5.

    a) Stateand deriveBragg s equation.

    4

    b) A cubic lattice have X-ray diffraction from (Ill), (200),

    (220), (311) and (222) planes. Determine the type of the

    cubic crystal. 3

    c) What is law of symmetry?How many symmetryelemt:nts

    are there in a simplecubic latticeand what are they? 3

    6.

    a) Whatdoyoumeanbydipolemoment?Whichone ispolar-

    NH) orBF)?Explain. 2+2

    b) Define specific rotation. On which factors does specific

    rotationdepend? 3

    [ Turn over

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    [ 4 ]

    c State and explainNernst Distribution law.

    3

    7. a How can you distinguish between electrochemical cell and

    electrolytic cell?

    3

    b What is calomel electrode?

    3

    c How can you titrate a weak acid by a strong alkali

    potentiometrically? 4

    8. a Compareconductanceof 0.1N HCIand 0.1N NaCI solution

    and explain. 3

    b Calculate the pH of a mixture of 10 ml 0.1 N AcOH

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    ~\

    V

    BACHELOROFCHEMICALENGINEERINGEXAMINATION,011

    ( 2nd Year, 1st Semester)

    NUMERICALMETHODS

    2

    f)-

    2roL ~ C.4.l~)

    E

    ExlCh.E/T/215/11/20111SPL

    Time: Three hours Full Marks: 100

    (50 marks for each part)

    Use a separate Answer-Script for each part.

    .

    PART- I

    Answer ny three questions.

    All questions do not carry equal marks.

    1. a) Consider a general 3x3 symmetric matrix in the following

    form :

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    [2 ]

    with the conditions, x ==Y==1 at t = o. Find the largest

    possible step size that you can use in solving the above set of

    equations by explicit Euler l11ethod. Perform one step

    integration with the above determined step size value.

    10+10=20

    2.

    a) Solve the following set of linearsimultaneousequations by

    .

    Thomas Algorithm:

    [

    ~ : ~I

    ][

    ~

    ]

    =

    [

    ~

    ]

    -1 3 x3 3

    b) DeriveDoolittle s Algorithm for solving a generalized set

    of linear simultaneous algebraic equation. What are the

    advantages or disadvantages of this method over

    conventionalGaussElimination? 8+7=I5

    3.

    Answer any three questions:

    x5= 5

    a) When and why will you use Pivoting strategy in solving a set

    of simultaneous algebraic equations?

    b) When will you call a system of equations to be ill-

    conditioned? What is condition number?

    c) Whatdo you meanby local truncationerror?How can you

    assess the stiffness of a set of ordinary differential

    equations?

    d) In some commercial software for solution of ODEs, the step

    size isvaried as the integration proceeds. Why is itdone so?

    ~

    [ 3 ]

    4.

    a) Considerthe followingset of equations:

    [

    2.1 5.7

    ][

    XI

    ] [

    1

    ]

    .8 10.3 x2 = 2

    It was observed that an attemptto solve the above set of

    equation by Gauss Elimination with two decimal place of

    accuracy results in a wrong solution. Explain this

    observationbasedonconditionnumber,derivedon the basis

    of SpectralNorm.

    b) Solvethe followingordinarydifferentialequation byHeun s

    method (predictor-corrector method) from x

    =

    0.0 to

    x =4.0 with a step size of 1.0.

    :

    =

    4eoosx 0.5y with the initial condition y =2.0 at

    5.

    x=O.

    a) Use Fadeev-Laverier s method to determine the

    characteristic polynomial for the x coefficient matrix as

    stated in problem 2(a).

    8+7=15

    b) Consider the following differentialequation, which can be

    developed by steady-stateheat balance for a long thin rod

    that is not insulated along itslength:

    d2T + h

    (

    T

    -

    T

    )

    =

    0 whereh is convective head transfer

    dx2 a

    coefficient (m-2) and Ta is the temperature of the

    surrounding air. Use Shooting method to solve the above

    [ Turn over

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    [ 5 ]

    [4]

    PART-II

    Answer any three questions.

    All questions carry equal marks.

    7. Use the methodof exploration followedby the method of false

    posi tion or chord) t o fi nd t he three roots of: 1.8xl - sin lOx

    =

    0

    with an accuracy of 0.001.

    equation for a 10m rod with h = 0.0Im-2, Ta=20C and

    use the followingboundary conditions :

    T 0)=40 and T 10)= 200.

    Hint Takeinitial guessvaluesfor ~~ tobe 10and 20.)

    7+8=15

    6. The one-dimensionalheat conduction problem in a rectangular

    fin can be expressed by the following parabolic partial

    differentialequation:

    8.

    Solve the equation: 2 10glOx - ~ + 1

    =

    0

    2

    Startingwith the values x=1 and x=5 with an accuracy of 0.001

    using Newton-Raphson Method.

    Fitthe followingtabular data to theArrhenius equation:

    k

    =

    Aexp - E

    I

    RT) by the method of least square where the

    symbolshave their usual significance.

    a T

    -=a.-

    at ax2

    The initial and the boundary conditionsfor the above PDE can

    be expressedas follows:

    9.

    i) At t = 0, T = 3 0, for all x , 0 ~ x ~ 1.

    ii) At x = 0, T = 150 for t > 0 .

    ill) At x = 1 ,

    or ax

    =0

    Develop the solution scheme for solving the apove PDE by

    Finite Difference FD) method taking 2 internal grid points

    with Crank-Nicholson method being used for solution of

    resultant set of ODE-IVPs. Develop the complete solution

    algorithmand perform one iteration. 15

    10. For the functiongiven as a table:

    determine the value of the argument corresponding to the value

    0.892914 of the function.

    [ Turn over

    T K)

    310

    350

    380 410 450

    k hr-l)

    1.7x 10-4

    0.018 0.31

    3.53 54.7

    x 1.435

    1.440

    1.445

    Y 0.892687

    0.893698

    0.894700

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    [ 6 ]

    1

    11. Calculate Jcosx dx using Simpson s formula by dividing the

    0 l+x

    interval 0, 1) into a total of four equal subintervals.

    12. Find the first derivative at the point x

    =

    50 for the function given

    as the following table:

    x

    50 55 60 65

    f 1.6990 1.7404

    1.7782 1.8129

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    ~

    Q --tJ

    ~v ~J~ ~ s.,J

    \.

    .

    (.f)

    Ex/Ch.E/MErr/213/1O/20 II

    sP

    BACHELOROF CHEMICALENGINEERINGEXAMINATION,011

    ( 2nd Year, 1st Semester)

    ENGINEERING THERMODYNAMICS

    Time: Three hours Full Marks: 100

    .

    Answer Question No.1 and any four from the rest.

    Steam and other tables are permitted if necessary.

    Assume any unfurnished data, consistent with the problem.

    .

    .

    1. A Define:Heat,Work,Environment.

    vb)

    x =6

    Plot the following diagrams for water:

    i) Isobaric processs on T-v plane from solid phase to

    superheated vapour phase. @.

    :Yp

    ,,;'

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    [ 2 ] [ 3 ]

    ill) specific heat supplied.

    jV) Plot the process on T-vplane.

    4+4+12=20

    and 150C,doing work. Heat loss from the system to the

    surrounding is 2 KJ during this process. Assuming the

    surrounding to be at 25Cand 100KPa, determine

    i) exergyof the steam atthe initial and final states.

    3. a) State the First lawof Thermodyanicsfor a cycle and hence

    deduce the first law for a non-cyclic process.

    b) Ina steam p~wer plant steam leaves the boiler at 2 MPa and

    300C. The steam then leaves the turbine and enters the

    condenser at IS KPa and 90% quality. Finally, it leaves the

    condenser and enters the pump at 14 KPa, 45C. The pump

    work is 4 KJ/Kg. Determine

    i) Turbine work.

    ii) Heat transfer in condenser and boiler.

    ill) Thermal efficiency of the plant.

    iv) Plot the process on T-S diagram.

    ii) exergy change of steam.

    ill) exergy destroyed.

    iv) The 2nd law of efficiency.

    f ---

    4+4+12=20

    6.

    a) Establish the Maxwell relations.

    6

    b) Define mean effective pressure.

    2

    8+12=20

    c) An air-standard Dieselcycle has a compression ratio of 16

    and a cut-off ratioof 2.At the beginningof the compression

    process, air is at 95KPa and 27C. Determine

    i) the temperature after the heat addition process.

    .

    4. a)/State the '2nd law of Thermodynamics' and show that

    ~~J '

    ...~ , entropy is a property.

    ~

    ~

    ~e.,,>' 7 ~~

    j?

    Onekilogramof Ammoniain a piston/cylinderarrangement -

    D

    'i/'\ at 50C, 1000 KPa is expanded in a reversible~ ~

    .

    of--

    '''d'

    .,~

    I