lab manual

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LABORATORY MANUAL

MEC-325

Thermo Fluid Engineering Laboratory

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TABLE OF CONTENTS.NO. TITLE OF EXPERIMENT PAGE NO.

1 Francis Turbine: To draw characteristics of Francis turbine 3

2Pelton turbine: To draw the characteristics of Pelton Turbine

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3Reciprocating pump: To determine the performance of areciprocating pump. 10

4Centrifugal pump: To draw the various performancecharacteristics of Centrifugal pump 14

5Hydraulic RAM : Determination of various efficiencies ofHydraulic Ram 18

6Diesel Engine: To draw valve timing diagram of a dieselengine, To study of its impact on the performance of an ICEngine.

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7Petrol Engine: To draw valve timing diagram of a petrolengine and study of its impact on the performance of an ICEngine.

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Morse test : Determine the brake power, indicated power andfriction power of a multicylinder petrol engine running atconstant speed determine the mechanical efficiency of amulticylinder petrol engine running at constant speed (MorseTest)

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Performance of diesel engine : Performance of a diesel fromno load to full load (at constant speed) for a single cylinderengine in terms of brake power, indicated power, mechanicalefficiency and SFC (Specific fuel consumption) and to obtainpower consumption curves and draw the heat balance sheet.

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Reciprocating compressor: To determine the isothermalefficiency, volumetric efficiency and compression ratio ofreciprocating compressor and Performance of single stage/multi stage reciprocating compressor..

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EXPERIMENT 1:

Aim: - To Study the constructional details of the Francis Turbine (Reaction turbine) and drawits fluid flow circuit.

Apparatus used: - Model of Francis Turbine.

Formula Used: -1. Work done by water on the runner per second = ρQ (VW1, V1)2. Hydraulic efficiency = Vw1 U1/(g×H)3. Speed Ratio = U1/ 2gH varies from 0.6 to 0.884. Flow Ratio = Vf1/ 2gH varies from 0.12 to 0.35Where ρ = Density of waterQ = Discharge of waterVw1= Whirl velocity of water at inletU1= Runner velocityVf1= Velocity of flow at inletH= Net head

Theory: - Reaction Turbine: - In this type of turbine there is a gradual pressure drop andtakes place continuously over the fixed and moving blades or over guide vanes and movingvanes. The function of the guides’ vanes is that they alter the direction of water as well asincreases its velocity. As the water passes over the moving vanes its kinetic energy isabsorbed by them.

Francis Turbine: - The inward flow reaction turbine having radial discharge at outlet isknown as Francis turbine, after the name of J.B Francis an American engineer who inbeginning designed inward radial flow reaction turbine. In the modern Francis turbine, thewater enters the runner of the turbine in the radial direction and leaves in the axial direction atthe outlet of the runner. Thus the modern Francis turbine is a mixed flow type turbine.

Constructional details:-The main parts of the Francis turbine are: -1. Penstock2. Casing3. Guide mechanism4. Runner5. Draft tube

1. Penstock: - It is a long pipe at the outlet of which a nozzle is fitted. The water fromreservoir flows through the penstock. The nozzle increases the kinetic energy of waterflowing through the penstock.2. Casing: - In case of reaction turbine, casing and runner are always full of water. The waterfrom the penstocks enters the casing which is of spiral shape in which area of cross-section ofthe casing goes on decreasing gradually. The casing completely surrounds the runner of theturbine. The casing is made of spiral shape, so that the water may enter the runner at constantvelocity throughout the circumference of the runner. The casing is made of concrete or caststeel.3. Guide Mechanism: - It consists of a stationary circular wheel all round the runner of theturbine. The stationary guide vanes are fixed on the guide mechanism. The guide vanes allow

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the water to strike the vanes fixed on the runner without shake at inlet. Also by a suitablearrangement, the width between two adjacent vanes of a guide’s mechanism can be altered sothat the amount of water striking the runner can vary.4. Runner: - It is a circular wheel on which a series of radial curved vanes are fixed. Thesurface of the vanes is made very smooth. The radial curved vanes are so shaped that thewater enters and leaves the runner without shock. The runners are made of cast steel, cast ironor stainless steel. They are keyed to the shaft.5. Draft tube: - The pressure at the exit of the runner of a reaction turbine is generally lessthan atmosphere pressure. The water at exit cannot be directly discharged to the tail race. Atube or pipe of gradually increasing area is used for discharging water from the exit of theturbine to the tail race. This tube of increasing area is called draft tube. The draft tube, inaddition to serve a passage for water discharge, has the following two purposes also.1. The turbine may be placed above the tail race and hence turbine may be inspectedproperly.2. The kinetic energy rejected at the outlet of the turbine is converted into useful pressureenergy.

Specifications:-1. Type –Reaction Turbine2. Type of flow – Mixed (Redial & Axial)3. Head –Medium 45 to 250m4. Specific speed – Medium 50 to 2505. Shaft position – Mainly vertical ( it may be horizontal also )6. Discharge – Medium

Governing Mechanism:-The governing mechanism changes the position of guide blades to affect a variation in thewater flow rate in the wake of changing load condition of the turbine. When the load changes,the governing mechanism rotates all guide blades about their axis through the same angle sothat the water flow rate to the runner and its direction essentially remain the same at the allpassages between any two consecutive guide vans. The penstock pipe feeding the turbine isoften fitted with a relief valve, also known as the pressure regulator. When guide vanes aresuddenly closed, the relief valve opens and diverts the water direct to tail race. Thesimultaneous operation of guide vanes and relief valve is termed as double regulation.Formulae Used

Total head = 10 x P (Pressure gauge reading)

Velocity of water= coefficient of pitot tube (2gH ((ρm/ρw)-1))1/2

ρw = density of water

ρm= density of manometer fluid

H= Differential pressure of manometer

BHP output= [(w1-w2) x (Db + Dr)/2 X 2x3.14xN]/4500

H.P. input = ρQH/75

Efficiency of turbine= [B.H.P./H.P. in] X100

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Date of Performance Worksheet for the student Registration no:

Aim: To Study the constructional details of the Francis Turbine (Reaction turbine) and drawits fluid flow circuit.

Observations:

A= C/S area of the pipeg= Acceleration due to gravityρw= Density of waterρm= Density of manometerD= Diameter of Break drumd= Diameter of ropeCpitote= Co-efficient of pitot tube

S. NORPM(N)

Pr. Gauge Reading(P)

Differentialpressure, h(m)

Dead weightw1(kg)

Spring Balancew2(kg)

Calculation:

S. No Velocity(v)

Total Head(m)

DischargeQ(m3/sec)

Output InputTurbine

Efficiency

Result and Discussion:

Error Analysis:

Learning Outcomes

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Aim: To Study the constructional details of the Francis Turbine (Reaction turbine) and drawits fluid flow circuit.

To be filled by Faculty

S.NO Parameter(Scale from 1-10, 1 for very poor and 10 for excellent)

Marksobtained

Max.Marks

1 Understanding of the student about the procedure /apparatus 202 Observations and analysis including learning outcome 203 Completion of the experiment, Discipline and cleanliness 10

Signature of Faculty

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EXPERIMENT 2:

Aim: To draw the characteristics of Pelton Turbine

Equipment required: Pelton wheel set up, Water supply, 3-Phase supply, 440 volt ACDrain Space required: 2.5mx1.5mx3.0m.

Material Required: Water needed, etc.

Learning Objective: To determine the output power of pelton turbine. To determine the efficiency of the pelton turbine. To plot the performance characteristics curves.

Outline of the Procedure:a. Clean the apparatus and make tank free from dustb. Close the drain valve provided.c. Fill sump tank ¾ with clean water and ensure that no foreign particles are there.d. Fill manometer fluid i.e. Hg in manometere. Now switch on the main power supply (440V AC, 50 Hz)f. The control valve is close position before starting the pump.g. Prime the pump and close valve after priming the pump.h. Switch on the pump with help of the starteri. Open the air release valve provided on the manometer, slowly to release the air frommanometerj. When there is no air in the manometer, close the air release valvek. Now regulate the spear position with the help of hand wheell. Now turbine is in operationm. Regulate the discharge by regulating the spear position.n. Load the turbine with the help of hand wheel attached to the spring balanceo. Note the manometer readingp. Note the pressure gauge readingq. Note the RPM of turbiner. Note the spring balance readingss. Repeat the same experiment for different load and different discharge

FormulaeHead (h) = h1-h2

V= Cd (2gH ((ρm/ρw)-1))1/2

Turbine Output = (2×9.81×3.14×N×W×Re)/60Where W= w1-w2+w3

Efficiency= outputx100/Input

Closing procedure:1. When experiment is over, first remove load on dynamometer2. Close the ball valves provided on dynamometer3. Switch off pump with the help of starter4. Switch off the mail power supply

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Scope of result and parametersCalculate the output power and efficiency of the pelton turbineTo plot the performance characteristics curves

Cautions:1. Do not run the pump at low voltage i.e. less than 390 volts2. Always keep apparatus free from dust3. To prevent clogging of moving parts, run the pump at least once in a fortnight.

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Aim: To draw the characteristics of Pelton Turbine

Observations:

d1=

a1=

g =

ρw=

ρm=

Db=

Dr=

Cd=

W3=

Re=

S. NO RPM

N

Pr. GaugeReading (P)

Differentialpressure, h(m)

H1 h2

Dead weightw1(kg)

Spring Balancew2(kg)

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Calculation:

S. No RPM Total Head(m)

DischargeQ(m3/sec)

Output Input TurbineEfficiency

Calculation:


Error Analysis:

Learning Outcomes:


S.NO Parameter (Scale from 1-10, 1 for very poor and 10for excellent)

Marks obtained Max. Marks

1 Understanding of the student about the procedure/apparatus

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2 Observations and analysis including learning outcome 203 Completion of the experiment, Discipline and

cleanliness10


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EXPERIMENT 3:

Aim: To determine the performance of a reciprocating pump.

Equipment required: Double acting-single cylinder Reciprocating pump, AC motor,pressure gauge, vacuum gauge, sump tank, measuring tank, stop watch etc.

Material required: water

Learning objectives: Study of this experiment involves investigate the characteristics ofreciprocating pump and to find out total head, pump efficiency, overall efficiency andvolumetric efficiency to plot the graph at various speeds, head Vs discharge and pumpefficiency Vs Discharge.

Outline of the procedure:a. Clean the apparatus and make all tanks free from dust.b. Close the drain valves provided.c. Fill sump tank ¾ with clean water and ensure that no foreign particles are there.d. Open flow control valve given on the water discharge line and control valve given onsuction line.e. Ensure that all on/off switches given on the panel are at off position.f. Set the speed of motor/pump with the help of 3 step cone pulley.g. Now switch ON the main power supply and switch ON the pump.h. Record the RPM of the motor from RPM indicator.i. Record discharge pressure by means of pressure gauge, provided on discharge line.j. Record suction pressure by means of vacuum gauge, provided at suction of the pump.k. Record the power consumption by means of energy meter, provided in panel with the helpof stop watch.l. Measure the flow of water, discharged by the pump, using stop watch and measuring tank.m. Repeat the same procedure for different pressure head.n. Repeat the same procedure for different RPM with the help of step cone pulley.Formula UsedHP electric = (p×3600×1000)/(t×EMC×746)P= No. Of pulses blinking in the energy metert=time for pulsesEMC= energy meter constant (3200EMC)H.P. Shaft= H.P.elec x 0.8 x 0.7Efficiency of motor=0.8Efficiency of transmission= 0.7Theoretical discharge= 2 x (A x L x N)/60A= Area of cross sectionL=Stroke LengthN= No. Of RPMActual discharge (Qa) = a x h/(100 x T)

a= Area of measuring tankh= Rise of water level in measuring tank (cm)T= Time for hTotal headH= [10 x (delivery pressure +Vacuum pressure /760)] +1 m

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HP of Pump= (ρQH/75)Whereρ= Density of fluidQ= actual DischargeH= Total HeadVolumetric Efficiency= [Actual discharge x 100]/Theoretical dischargeOverall efficiency= [H.P. of pump x 100]/H.P. of elecPump efficiency = [H.P. of pump x 100]/ H.P. of shaft

Scope of the results expected: Neat schematic diagram of experimental setup. Observation table. Calculation of theoretical discharge, actual discharge. Calculation of total head and volumetric efficiency and overall efficiency, pump

efficiency. Plot the graph of head Vs discharge and pump efficiency Vs discharge.

Cautions:1. It should be ensured that there are no air bubbles.2. There should be no leakage of water from the pipe as well as from measuring tank.3. All readings and measurements should be taken very carefully and accurately.

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Observation Table:

S. No. RPM ofPump

No. OfPulsesof P

Timetakenby p

SuctionPressure

mm Hg

DeliveryPressure

Kg/cm2

Ht. In MeasuringTank h (cm)

h1 h2

Timetakenfor h(T) sec

Calculation:

S.No

H.P.elec

H.P.shaft

TheoreticalDischarge

Actualdischarge

Totalhead

HPoutput

Volumetricefficiency

Overallefficiency

Pumpefficiency


Error Analysis:

Learning Outcomes:

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EXPERIMENT 4:

Aim: To draw the various performance characteristics of Centrifugal pump:1. Head vs Discharge2. Power vs Discharge3. Efficiency vs Discharge

Equipment required: Single stage Centrifugal Pump, Measuring tank, Scale, Sump etc

Learning objective: The centrifugal pumps are designed and manufactured to work under agiven set conditions (such as discharge, speed, power required, head, efficiency etc.) but inactual practice the conditions may be different than those designed conditions. It is importantto determine the exact behaviour of the pump under varied conditions

Outlines of the procedure:1. Different values of Q (discharge) and H (manometric head) are obtained by running thepump at a constant.2. Calculate the power (P1) output of the pump for each set of values of Q and H, P1 = wQ H(w = specific weight of water = 9810N/m3)3. Calculations are made for the overall efficiency (ή) of the pump (for each value of P) ή =power output of the pump/power input of the pump = P1/P24. The curves are plotted between a. Q and H b. Q and P c. Q and ήFormulaeP=

×× kW

P=pulses of energyT= Time take by PE=Energy meter constant

Pshaft=Pelec.×ɳmotor

ɳmotor=0.8 (assumed)DischargeQ= [A x h]/100×tA= area of collecting tankh= height of collecting tankh1,h2= Initial and final level of water in tankt= Time taken for h(sec)H= [10×(delivery pressure + Vacuum pressure/760]+1 m of heightPpump=ρQH/100Ρ= density of fluidH= total headɳoverall= [Ppump×100]/Pelec.ɳpump= [Ppump×100]/Pshaft.

Required results: From the graphs, it is observed that the value of head will rise as dischargeincreases, the value of discharge will increase with the increase in shaft horse power and theefficiency will increase as discharge increases.

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Cautions:1. It should be ensured that there are no air bubbles.2. There should be no leakage of water from the pipe as well as from measuring tank.3. All readings and measurements should be taken very carefully and accurately.

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Aim: To draw the various performance characteristics of Centrifugal pump:1. Head vs Discharge2. Power vs Discharge3. Efficiency vs Discharge

Observation Table:

S. No. RPM ofPump

Gaugepressure

(kg/cm2)

Vacuum(mm Hg)

10pulses /t

Ht. In MeasuringTank h (cm)

h1 h2

Time taken forh (T) sec

Calculation:

S. No P. elec P. shaft Actualdischarge

Total head Pulses ofenergyforpump

Overallefficiency

Pump efficiency


Error Analysis:

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Aim: To draw the various performance characteristics of Centrifugal pump:Learning Outcomes:





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EXPERIMENT 5:

Aim: Determination of various efficiencies of Hydraulic Ram.

Apparatus Used: - Model of Hydraulic Ram.

Theory: - Hydraulic System: - is an arrangement to transmit forces and energy through anincompressible fluid.

They are of two types:-

1. Hydrostatic System: - In this system transmission is due to hydraulic pressure. The mainelements are: -

(a). Pumping Unit: - That acts as a power source to develop the hydraulicpressure from mechanical work- Usually it is a rotary or a reciprocating pump.

(b). Transmission line or passage: - Through which power and energy are to betransmitted from the place of production to the place of its necessity.

(c). Hydraulic motor: - To reconvert the hydraulic pressure into mechanicalwork. Again this can be of rotary or reciprocating type in the form of cylinder& piston. Piston in the cylinder is moved by the fluid pressure providinguseful work. e.g. Hydraulic press, crane, lift etc.

2. Hydro Kinematics System: - In this transmission is due to change in the velocity and thedirection of fluid flow. With a negligible change in the pressure of the fluid. It has two mainelements: -

(a). Pump- impeller driven by the driving shaft (centrifugal pump).

(b). Turbine Runner to run the driven shaft: - There is circulation of oil fromthe pump impeller to the runner that transmits power.

Hydraulic Ram: - It is a pump which raises small quantity of water to a greater height, iflarge qty. of water is available at a lower height without using any external power.

Constructional details: - Its main parts are: -

Supply line, Supply tank, Waste valve, Delivery valve, Valve chamber, Delivery pipe,Delivery tank, Air vessel, Non-return valve, Drain cock, Pressure gauge.

Working principle: - It works on the principle of water hammer effectors inertia force ofwater in a pipe line. When a flowing fluid is brought to rest suddenly a rise of pressureoccurs, which can be utilized to raise a portion of water to a higher level. It does not requireany external power for its operation.

It consist of a valve chamber fitted with two valves, a wattle valve & a delivery valve, bothbeing none return valves. The delivery valve opens into an Air vessel to carry the aircompressed. A delivery pipe is connected to the air vessel to carry the water to a delivery

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tank. A supply pipe connects the available water source to the valve chamber. At a particularmoment assume that the delivery valve is closed and the waste valve is open. Water flowsdown the supply pipe in to the valve chamber and then through the waste valves into wastewater tunnel. As the velocity of water in the pipe increases, the dynamic pressure on theunderside of the waste valve becomes high. This closes the waste valve which was open dueto its own weight. With the sudden closure of the waste valve, the velocity reduces to zero.

Formulae:

D’Aubuisson’s Efficiency:

ɳA= (qxhd)/(q+Q)hs

Rankine Efficiency:

ɳR= (qxhd)/(QXhs)

Where:

q= Discharge of water lifted up

Q=Discharge of waste water

hd= Delivery Head of the RAM

hs= Head of water supplied to RAM

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Observations:

Sr. No. Water Height ofUseful Water

Timetaken forh1 (t sec)

Water Height ofwaste water

h21 h21

Timetaken forh2 (t sec)

Pressure

(P)

Calculation:

S. No. Discharge ofwaste water

(Q)(m3/sec)

Discharge ofuseful water

(q) (m3/sec)

Deliveryhead

(hd)

Efficiency

ɳA

Efficiency

ɳR


Error Analysis:

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Learning Outcomes:







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EXPERIMENT 6:

AIM:- To draw valve timing diagram of a diesel engine, To study of its impact on theperformance of an IC Engine

APPARATUS USED:- Four-Stroke, Single-Cylinder Diesel Engine Test Rig, Sprit Level,Pencil, and Device for measuring crank angle.

THEORY:-In four- stroke S. I. Engine the opening and closing of the valves, and the ignition of the airfuel mixture do not take place exactly at the dead centre positions. The valve open slightlyearlier and close after their respective dead centre positions. The ignition also occurs prior, tothe mixture is fully compressed, and the piston reaches the top dead centre position. Similarlyin a C. I. Engine both the valves do not open and close exactly at dead centre positions, ratheroperate at some degree on either side in terms of the crank angles from the dead centrepositions. The injection of the fuel is also timed to occur earlier.

PROCEDURE:-1) Fix a plate on the body of the Engine touching the flywheel.2) Mark the positions of the both the dead centers on the flywheel with the reference to thefixed plate. For vertical engines mark TDC and BDC. In case of horizontal Engines markIDC and ODC3) Mark on the flywheel when the inlet and exhaust valves open and close as the flywheel isrotated slowly.4) Measure the valves (Tappet) Clearance.5) Mark the spark ignition timing in case of petrol Engine and fuel injection timing in case ofDiesel Engine.6) Measure the angles of the various events and plot the valve timing diagram.

RESULT:-Based on final calculation valve timing diagram is drawn and compare with thestandard valve timing diagram.

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Aim: To draw valve timing diagram of a diesel engine, to study of its impact on theperformance of an IC EngineObservation Table:

Calculation:


Error Analysis:

Learning Outcomes:





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EXPERIMENT 7:

AIM:- To Study and Determine the effect of A/F Ratio on the performance of the Two-Stroke, Single-Cylinder Petrol Engine.

APPARATUS USED :-Two-Stroke, Single-Cylinder Petrol Engine Test Rig, Stop Watch,and Digital Tachometer.

THEORY:-Air fuel ratio has a major effect on the performance of the I. C. Engine. The Airfuel ratio of aS. I. Engine lies in the range of 10: 1, to 22: 1 depends upon the power requirements and theeconomic running of the engine. Richer mixtures are required for idle and full throttlerunning of the engine. Whereas for the mid-range , weaker mixtures are required. Themixture corresponding to the minimum fuel consumption is known as the Best EconomyMixture. It is nearly 15:1.Accurate measurement of air flow into the engine isdifficult toachieve in practice, due not only to the nature of the air itself, but also the conditions underwhich the measurement has to be made.The common method of measuring the air flow rate isthe tank and orifice method. During suction stroke the pressure inside the tank is less than theatmospheric pressure. The air enters the tank through the orifice plate , and by applying theBernaulli’s equation the air flow rate can be measured. The fuel consumption can bemeasured by noting down the fuel consumed during specified time. Thus the air fuel ratio canbe set to desired value. The accuracy of the air flow measurement depends on the steady stateconditions of air flow through the orifice and the damping of the pulsating effect.

FORMULE USED:-(i) Torque, T = 9.81 x W x R Effective N-m.32 ; Where R Effective = (D + d)/ 2 m, and W (Load) = ( S1 - S2 ) Kg,(ii) Brake Power, B P = ( 2πN T ) / 60, 000 KW ; Where N = rpm, T = Torque N-m,(iii) Fuel Consumption, m f = ( 50 ml x 10 -6 x ρ Fuel ) / ( t ) Kg/Sec.Here; 1 ml = 10-3liters, and 1000 liters = 1 m3

So, 1 ml = 10-6 m3

(iv) Brake Specific Fuel Consumption, BSFC = ( m f x 3600 ) / B P Kg/ KW . hr(v) Mass of the Air, m Air = Cd Ao √2 g Δh ρ Air ρ Water Kg/ Sec(vi) Air Fuel Ratio, A/F = ( m Air / m f ) Kg/ Kg of Fuel

PROCEDURE:-1. Before starting the engine check the fuel supply, and lubrication oil.2. Set the dynamometer to zero load.3. Run the engine till it attains the working temperature and steady state condition.4. Adjust the dynamometer load to obtain the desired engine speed.5. Note down the dynamometer load reading and fuel consumption rate.6. Repeat the experiments for various air fuel ratios and different loads, and same speed.7. Disengage the dynamometer, and stop the engine.8. Do the necessary calculation, and plot the graphs.

RESULTS:-Performance curves are plotted and they are similar to the standard performanceCurves.

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Aim: To study and draw the valve timings diagram Four-Stroke, Single-Cylinder PetrolEngine.

Observation Table:

Calculation:


Error Analysis:

Learning Outcomes:





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Petrol Engine

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EXPERIMENT 8:

AIM: - Determine the brake power, indicated power and friction power of a multi cylinderpetrol engine running at constant speed (Morse Test), Determine the mechanical efficiency ofa multi cylinder petrol engine running at constant speed (Morse Test).APPARATUS USED: - Multi-Cylinder Petrol Engine Test Rig, Stop Watch, Hand Gloves,and Digital Tachometer.

THEORY:-The purpose of Morse Test is to obtain the approximate Indicated Power of a Multi-cylinderEngine. It consists of running the engine against a dynamometer at a particular speed, cuttingout the firing of each cylinder in turn and noting the fall in BP each time while maintainingthe speed constant. When one cylinder is cut off, power developed is reduced and speed ofengine falls. Accordingly the load on the dynamometer is adjusted so as to restore the enginespeed. This is done to maintain FP constant, which is considered to be independent of theload and proportional to the engine speed. The observed difference in BP between allcylinders firing and with one cylinder cut off is the IP of the cut off cylinder. Summation ofIP of all the cylinders would then give the total IP of the engine under test.

FORMULE USED:-(i) Brake Power, BP = WN/ C KW; Where W = Load on the Dynamometer Kg, N = rpm of the Engine, andC = Dynamometer Constant.(ii) Indicated Power ( IP ) of each Cylinders:IP1 = ( BPT - BP2,3,4 ) KWIP2 = ( BPT - BP1,3,4 ) KWIP3 = ( BPT - BP1,2,4 ) KWIP4 = ( BPT - BP1,2,3 ) KW(iii) Total IP of the Engine, IPT = ( IP1 + IP2 + IP3 + IP4 ) KW(iv) Mechanical Efficiency, η mechanical = BPT / IPT

PROCEDURE:-1. Before starting the engine check the fuel supply, lubrication oil, and availability of coolingwater.2. Set the dynamometer to zero load.3. Run the engine till it attains the working temperature and steady state condition. Adjust thedynamometer load to obtain the desired engine speed. Record the engine speed anddynamometer reading for the BP calculation.4. Now cut off one cylinder. Short-circuiting its spark plug can do this.5. Reduce the dynamometer load so as to restore the engine speed as at step 3. Record thedynamometer reading for BP calculation.6. Connect the cut off cylinder and run the engine on all cylinders for a short time. This isnecessary for the steady state conditions.7. Repeat steps 4, 5, and 6 for other remaining cylinders turn by turn and record thedynamometer readings for each cylinder.8. Bring the dynamometer load to zero, disengage the dynamometer and stop the engine.9. Do the necessary calculations.

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OBSERVATIONS:-Engine Speed, N = rpmNo. of Cylinders, n = FourCalorific Value of Fuel, C.V. = 42,000 KJ/Kg

RESULT:-Total IP of the Multi-Cylinder Petrol Engine by Morse Test.

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Aim: Determine the brake power, indicated power and friction power of a multi cylinderpetrol engine running at constant speed (Morse Test), Determine the mechanical efficiency ofa multi cylinder petrol engine running at constant speed (Morse Test)Observations:

Engine Speed, N = _________rpmNo. of Cylinders, n = _______Observation Table

Calculation:


Error Analysis:Learning Outcomes:





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EXPERIMENT 9:

AIM:- Performance of a diesel from no load to full load (at constant speed) for a singlecylinder engine in terms of brake power, indicated power, mechanical efficiency and SFC(Specific fuel consumption) and to obtain power consumption curves and draw the heatbalance sheet

APPARATUS USED: - Four-Stroke, Single-Cylinder (Constant Speed) Diesel EngineTestRig, Stop Watch, and Digital Tachometer.

THEORY:-Under some circumstances (i.e Electric Generator) C. I. Engines are required torun at constant speed. For this purpose the test is to be performed at constant speed and theload is varied from zero to maximum. When load on the engine increases its speed decreases.Accordingly the fuel supply is adjusted to keep the engine speed constant. Corresponding toeach load setting, dynamometer readings and fuel consumption rate are measured. The BP,BSFC, BMEP, A/F, and Mechanical Efficiency are calculated from measured data andplotted against the load.

FORMULE USED:-(i) Torque, T = 9.81 x W x R Effective N-m.Where R Effective = (D + d)/ 2 or (D + tBelt)/ 2 m, and W (Load) = ( S1 - S2 )Kg,(ii) Brake Power, B P = ( 2πN T ) / 60, 000 KW

Where N = rpm, T = Torque N-m,(iii) Fuel Consumption, m f = ( 50 ml x 10 -6 x ρ Fuel ) / ( t ) Kg/Sec.Here; 1 ml = 10-3 liters, and 1000 liters = 1 m3

So, 1 ml = 10-6 m3

(iv) Brake Mean Effective Pressure, BMEP = (BP x 60,000)/ ( L Stroke x A x N’) N/ m2

(v) Air Fuel Ratio, A/F = ( m Air / mf ) Kg/ Kg of Fuel(vi) Mechanical Efficiency, η mechanical = BP / IP

PROCEDURE:-1. Before starting the engine check the fuel supply, lubrication oil, and availability of coolingwater.2. Set the dynamometer to zero load.3. Run the engine till it attains the working temperature and steady state condition.4. Adjust the dynamometer load to obtain the desired engine speed. Note down the fuelconsumption rate.5. Change the dynamometer load so that the engine speed Change, to maintain the enginespeed constant fuel consumption increases.6. Note down the fuel consumption rate, speed, air inlet temperature, at this load setting.7. Repeat steps 5 and 6 for various loads.8. Disengage the dynamometer and stop the engine.9. Do the necessary calculation.

RESULTS:-Performance curves are plotted and they are similar to the standard performanceCurves.

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Aim: Performance of a diesel from no load to full load (at constant speed) for a singlecylinder engine in terms of brake power, indicated power, mechanical efficiency and SFC(Specific fuel consumption) and to obtain power consumption curves and draw the heatbalance sheet.

Observations:

Calculation:

(i) Torque, T = __________________________(ii) Brake Power, B P = ___________________(iii) Fuel Consumption, mf = ________________(iv) Brake Mean Effective Pressure, BMEP = _________________(v) Air Fuel Ratio, A/F = ___________________________(vi) Mechanical Efficiency, η mechanical = ________________


Error Analysis:

Learning Outcomes:

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Aim: Performance of a diesel from no load to full load (at constant speed) for a singlecylinder engine in terms of brake power, indicated power, mechanical efficiency and SFC(Specific fuel consumption) and to obtain power consumption curves and draw the heatbalance sheet.





20


cleanliness10


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EXPERIMENT 10:

Aim: To determine the isothermal efficiency, volumetric efficiency and compression ratio ofreciprocating compressor and Performance of single stage/ multi stage reciprocatingcompressor.Description: The Air Compressor is a two stage, reciprocating type. The air is sucked fromatmosphereand compressed in the first cylinder. The compressed air then passes through theaircooler into the second stage cylinder, where the air is further compressed. The air furthergoes to the air reservoir through safety valve, which operates the electrical switch, when thepressure exceeds the limit. The test unit consists of a air chamber, containing an orifice plate,the manometer, compressor, an electrical dynamometer type induction motor.

Equipment Data:1. Diameter of low pressure cylinder2. Diameter of high pressure cylinder3. Length of stroke4. Maximum discharge pressure5. Compressor speed6. Motor speed7. H.P. of Motor8. Orifice Diameter9. Coefficient of discharge of orifice10. Area of Orifice11. Dynamometer Arm Length

Procedure:1. The outlet valve is closed.2. The dynamometer is adjusted, so that the circular balance reads zero, when the pointers atthe motor pedestal coincide. This can be easily done by operating thehandwheel.3. The manometer connections are checked. (The manometer may be filled with water uptothe half level.)4. The compressor is started. The pressure develops slowly5. At the particular pressure, the outlet valve is opened slowly and adjusted so thatthe pressure is maintained constant.6. Take the all readingsFormulae

QNTP= × ×([ ]QRTP=QNTP×

Swept Volume =[ ×d2×L×N]/60×4

Graphs:Draw Graphs1. Pressure Ratio Vs. Volumetric Efficiency2. Pressure Ratio Vs. Isothermal Efficiency3. Pressure Ratio Vs. Input / shaft power to compressor4. Pressure Ratio Vs. Free air delivered.

DO’s

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1. Keep Air Inlet portion clean.2. Check current belt tension.3. Current Oil Level in the crankier to be maintained.4. Drain daily by opening Drain Cock.5. If you hear any unusual sound, please attend immediately.6. Use safety glasses or goggles.

DO NOT’s1. Do not neglect the routine checking.2. Do not neglect any leakage in the system.3. Do not do any meddling or adjustment while compressor is working.4. Do not keep any loose tools on compressor.5. Do not run the compressor without belt yard.6. Do not use any cleaning agents while changing oil.7. Do not inhale compressed air directly.8. Do not use the compressor in the rain or any explosive atmosphere.9. Do not tamper with safety valve, occasionally pull the ring on the changesetting of safety valve to make sure that the valve operate freely.

Precautions:1. The orifice should never be closed, otherwise the manometer liquid (water) will be suckedinto the tank.2. At the end of the experiment the outlet valve at the reservoir should be opened, as thecompressor is to be started again at low pressure, to prevent undue strain on the piston.

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Aim: To determine the isothermal efficiency, volumetric efficiency and compression ratio ofreciprocating compressor and Performance of single stage/ multi stage reciprocatingcompressor.Observations:

S.NO DeliveryPressure

DifferentialManometerreading

RPM Inlet Force

S.NO ΔP QNTP QRTP isothermalefficiency

volumetricefficiency

Calculations:

Graphs:Draw Graphs1. Pressure Ratio Vs. Volumetric Efficiency2. Pressure Ratio Vs. Isothermal Efficiency3. Pressure Ratio Vs. Input / shaft power to compressor4. Pressure Ratio Vs. Free air delivered.


Error Analysis:

Learning Outcomes:





20


cleanliness10


lab manual

Documents

type of turbine

modern francis turbine

model of francis turbine

case of reaction turbine

radial flow reaction

inward flow reaction

mixed flow type turbine

b francis