Me 311 Manual

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Laboratory Manual

THERMALLABORATORY

DEPARTMENT OF MECHANICALENGINEERING

Prepared by:Deepak paliwal

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LIST OF EXPERIMENTS

SERIAL

NO.

NAME OF EXPERIMENT HOURS

1 STUDY OF 2 STROKE/4STROKE PETROL ENGINE 2

2 STUDY OF 2 STROKE/4 STROKE DIESEL ENGINE 2

3 PORT TIMING DIAGRAM OF SINGLE CYLINDER

TWO STROKE SPARK IGNITION ENGINE

2

4 VALVE TIMING DIAGRAM OF A SINGLE

CYLINDER FOUR STROKE COMPRESSION

IGNITION ENGINE

2

5 PERFORMANCE TEST ON RECIPROCATING

AIR COMPRESSOR

2

6 PERFORMANCE TEST ON FOUR STROKE FOUR

CYLINDER PETROL ENGINE

2

7 PERFORMANCE TEST ON FOUR STROKE FOUR

CYLINDER DEISEL ENGINE

2

8 HEAT BALANCE TEST ON FOUR CYLINDER

FOUR STROKE SPARK IGNITION

ENGINE

2

9 HEAT BALANCE TEST ON FOUR CYLINDER

FOUR STROKE COMPRESSION IGNITION

ENGINE

2

10 TO FIND INDICATED HOURSE POWER ON

MULTICYLINDER PETRIL ENGINE BY MORSE TEST

2

11 FLASH AND FIRE POINT TEST BY

CLEAVE LAND OPEN CUP APPARATUS

2

12 STUDY OF WATER TUBE AND FIRE TUBE BOILER 2

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EXPERIMENT NO.1

Aim: - To Study the construction details & working principal of 2-Stroke / 4-Stroke

Petrol Engine.

Apparatus : - Models of 2-Stroke / 4-Stroke Engines.

Theory:- The working Principle of Engines.

2-Stroke (S.I) EnginesIn a 2-Stroke engine, the filling process is accompanied by the change compressed in a

crank case or by a blower. The induction of compressed charge moves out the product

of combustion through exhaust ports. Therefore, no piston stroke is required. Out ofthese 2-strokes, one stroke is for compression of fresh charge and second for power

stroke.

The charge conducted into the crank case through the spring loaded valve when thepressure in the crank case is reduced due to upward motion of piston during the

compression stroke. After the compression & ignition expansion takes place in usual

way.

During the expansion stroke the charge in crankcase is compressed. Near the end of theexpansion stroke, the piston uncovers the exhaust ports and the cylinder pressure drops

to atmosphere pressure as combustion produced leave the cylinder.

Four Stroke (S.I) EngineIn a four stroke engine, the cycles of operations is completed in 4 strokes of piston or 2revolution of crank shaft. Each stroke consists of 180 & hence the fuel cycle consists

of 720 of crank rotation. The 4-Strokes are: -Suction or Intake Stroke : - It starts at, when the piston is at top dead centre & about to

move downwards. The inlet valve is open at that time and exhaust valve is closed due

to suction created by the motion of the piston towards the bottom dead centre, thecharge containing air fuel mixture is drawn into the cylinder. When the piston reaches

BDC the suction stroke ends and inlet valve is closed.

Compression Stroke : - The charge taken into the cylinder during suction stroke iscompressed by return stroke of piston. During this stroke both the valves are closed.

The mixture which fills the entire cylinder volume is now compressed into the

clearance volume. At the end, the mixture is ignited with the help of electrode of sparkplug. During the burning process the chemical energy of fuel is converted to heat

energy. The pressure is increased in the end due to heat release.Expansion Stroke : - The burnt gases escape out and the exhaust valve opens but inlet

valve remaining closed the piston moves from BDC to TDC and sweeps the burnt gasesout at almost atmospheric pressure. The exhaust valve gets closed at the end of this

stroke. Thus, for one complete cycle of engine, there is only one power stroke while

crank shaft makes 2 revolutions.

Exhaust Stroke : - During the upward motion of the piston, the exhaust valve is openand inlet valve is closed. The piston moves up in cylinder pushing out the burnt gases

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through the exhaust valve. As the piston reaches the TDC, again the inlet valve opens

and fresh charge is taken in during next downward movement of the piston and thecycle is repeated.

Construction Details

Cylinder : - It is a cylindrical vessel or space in which the piston makes areciprocating produces.

Piston: - It is a cylindrical component fitted into the cylinder forming the movingboundary of combustion system. It fits in cylinder perfectly.

Combustion Chamber : - It is the space enclosed in the upper part of cylinder, by thecylinder head & the piston top during combustion process.

Inlet Manifold : - The pipe which connects the intake system to the inlet valve ofengine.

Exhaust Manifold : - The pipe which connects the exhaust system to the exhaustvalve of engine.

Inlet / Exhaust Valves : - They are provided on the cylinder head to head to regulatethe charge coming into or going out of the chamber.Spark Plug : - It is used to initiate the combustion process in S.I engines.Connected Rod : - It connects piston & the crank shaft.Crank shaft : - It converts the reciprocating motion of the piston into useful rotary

motion of output shaft.

Gudgeon pins : - It forms a link between connection rod and the piston.Cam shaft : - It controls the opening & closing of the valves.Cam : - They open the valves at the correct tunes.Carburetor : - Used in S.I engine for atomizing & vaporizing and mixture it with air

in varying proportion.

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EXPERIMENT NO.2

Aim : - To study the constructional details & working principles involved in a2-

Stroke & 4-Stroke Diesel Engines.

Apparatus : - Model of 2-Stroke / 4-Stroke Diesel Engine.

Theory : -

Two Stroke (C.I.) EngineIn two stroke engines, the cycle is completed in one revolution of the crankshaft.In 2-stroke engine, the filling process is accomplished by the charge compressed

in crankcase or by a blower. The induction of compressed charge moves out of

the exhaust ports. Therefore, no piston strokes are required for these 2 operations.

Two strokes are sufficient to complete the cycle one for compressing the freshcharge and other for expansion or power stroke.

1. Compression: - The air or charge is inducted into the crankcase through the springloaded inlet valve when the pressure in crankcase is reduced due to upward

motion of piston.

2. Expansion : -During this, the charge in the crankcase is compressed. At the end the piston

uncovers the exhaust ports and cylinder pressure drops to the atmospheric

pressure. Further movement of piston opens the transfer ports, permitting the

slightest compressed charge in the crankcase to enter the engine cylinder.


1. Cylinder : - In it the piston makes a reciprocating process motion.

2. Piston: - It is a cylindrical component fitted into the cylinder forming the

moving boundary of the combustion system. It fits into cylinder.3. Combustion Chamber : - The space enclosed in the upper part of the cylinder,

by the head and the piston top during the combustion process.

4. Inlet/ Outlet ports : - They are provided on the side of cylinder to regulate thecharge coming in and out of cylinder.

5. Fuel Injector : - It injects the fuel in combustion chamber to initiate

combustion process for power stroke.

6. Connecting Rod : - It interconnects crank shaft and the piston.

7. Fly Wheel : - The net torque imparted to the crankshaft during one completecycle of operation of the engine fluctuates cow sing change in angular velocity

of shaft. In order to achiever uniform torque an internal mass is attached to the

output shaft & this is called as fly wheel. Four Stroke (C.I.) Engine

In four strokes C.I. Engine compression ratio is from 16 to 20. During suctionstroke air is inducted. In C.I. engines high pressure. Fuel pump and injectors are

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provided to inject the fuel into combustion chamber and ignition chamber system

is not necessary.

1. Suction : - During suction stroke, air is inducted through inlet valve.2. Compression : - The air inducted is compressed into the clearance volume.3. Expansion : - Fuel injection starts nearly at the end of the compression stroke.

The rate of injection is such that the combustion maintains the pressure constantinspired of piston movement on its expansion stroke increasing the volume. After

injection of fuel, the products of combustion chamber expand.

4. Exhaust : - The piston traveling from BQC to TDC pushes out the products ofcombustion out of cylinder.


1. Cylinder: It is a cylindrical vessel in which a piston makes up and down motion.

2. Piston: It is a cylindrical component making up and down movement in thecylinder.3. Combustion Chamber: It is the portion above the cylinder in which the

combustion of the Fuel-air mixture takes place.

4. Inlet and Exhaust valves: The inlet valves allow the fresh fuel-air mixture toenter the combustion chamber and the exhaust valve discharges the products ofcombustion.

5. Crank Shaft: It is a shaft which converts the reciprocating motion of piston intothe rotary motion.

6. Connecting Rod: The connecting rod connects the Piston with the crankshaft.7. Cam shaft: The cam shaft controls the opening and closing of inlet and Exhaust

valves.8. Fuel Injector: It is located at the top of head to inject the fuel into the combustionchamber.

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EXPERIMENT NO. 3

AIM :-To draw the port timing diagram of a two stroke spark ignition engine.

APPARATUS REQUIRED:

1. A two stroke petrol engine2. Measuring tape

3. Chalk

BRIEF THEORY OF THE EXPERIMENT:The port timing diagram gives an idea about how various operations are taking place in

an engine cycle. The two stroke engines have inlet and transfer ports to transfer thecombustible air fuel mixture and an exhaust port to transfer exhaust gas after combustion.

The sequence of events such as opening and closing of ports are controlled by the

movements of piston as it moves from TDC to BDC and vice versa. As the cycle of

operation is completed in two strokes, one power stroke is obtained for every crankshaft

revolution. Two operations are performed for each stroke both above the piston (in thecylinder) and below the piston (crank case). When compression is going on top side of

the piston, the charge enters to the crank case through inlet port. During the downwardmotion, power stroke takes place in the cylinder and at the same time, charge in the crank

case is compressed and taken to the cylinder through the transfer port. During this period

exhaust port is also opened and the fresh charge drives away the exhaust which is known

scavenging. As the timing plays major role in exhaust and transfer of the charge, it isimportant to study the events in detail. The pictorial representation of the timing enables

us to know the duration and instants of opening and closing of all the ports. Since one

cycle is completed in one revolution i.e. 360 degrees of crank revolution, variouspositions are shown in a single circle of suitable diameter.

PROCEDURE1.Mark the direction of rotation of the flywheel. Always rotate only in clockwise

direction when viewing in front of the flywheel.

2.Mark the Bottom Dead Center (BDC) position on the flywheel with the referencepoint when the piston reaches the lowermost position during rotation of the

flywheel.

3.Mark the Top Dead Center (TDC) position on the flywheel with the referencepoint when the piston reaches the top most position during the rotation of flywheel.

4.Mark the IPO, IPC, EPO, EPC, TPO, and TPC on the flywheel observing thefollowing conditions.

5.Inlet port open (IPO) when the bottom edge of the piston skirt just opens thelower most part of the inlet port during its upward movement.

6.Inlet port close (IPC) when the bottom edge of the piston fully reaches the lowermost part of the inlet port during its downward movement.

7.Transfer port open (TPO) when the top edge of the piston just open the top mostpart of the transfer port during its downward movement.

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8.Transfer port close (TPC) when the top edge of the piston fully reaches the uppermost part of the transfer port during its upward movement

9.Exhaust port open (EPO) when the top edge of the piston just opens the top mostpart of the exhaust port during its downward movement.

10.Exhaust port close (EPC) when the top edge of the piston fully reaches the uppermost part of the exhaust port during its up ward movement

11.Measure the circumferential distance of the above events either from TDC orfrom BDC whichever is nearer and calculate their respective angles.

12.Draw a circle and mark the angles.

OBSERVATION TABLE:

Circumference of flywheel (L) = mm

Sl.No. Description Distance in mm Angle in Degrees1. IPO before TDC

2. IPC after TDC

3. EPO before BDC

4. EPC after BDC

5. TPO before BDC

6. TPC after BDC

FORMULA:

L

Angle = ----- 360

X

Where, LDistance from nearest dead center in mmX- Circumference of the Flywheel in mm

RESULT:

The given two-stroke petrol engine is studied and the Port timing diagram is drawn for

the present set of values.

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EXPERIMENT NO. 4

AIM:-To draw the valve timing diagram of the four stroke compression ignitionengine.

APPAATUS REQUIRED:

1. Experimental engine

2. Measuring tape

3. Chalks

BRIEF THEORY OF THE EXPERIMENT:

The valve timing diagram gives an idea about how various operations are taking place in

an engine cycle. The four stroke diesel engines have inlet valve to supply air inside the

cylinder during suction stroke and an exhaust valve to transfer exhaust gas after

combustion to the atmosphere. The fuel is injected directly inside the cylinder with the

help of a fuel injector.

The sequence of events such as opening and closing of valves which are performed by

cam- follower-rocker arm mechanism in relation to the movements of the piston as it

moves from TDC to BDC and vice versa. As the cycle of operation is completed in four

strokes, one power stroke is obtained for every two revolution of the crankshaft. The

suction, compression, power and exhaust processes are expected to complete in the

respective individual strokes. Valves do not open or close exactly at the two dead centers

in order to transfer the intake charge and the exhaust gas effectively. The timing is set in

such a way that the inlet valve opens before TDC and closes after BDC and the exhaust

valve opens before BDC and closes after TDC. Since one cycle is completed in two

revolutions i.e 720 degrees of crank rotations, various events are shown by drawing

spirals of suitable diameters. As the timing plays major role in transfer of the charge,

which reflects on the engine performance, it is important to study these events in detail.

PROCEDURE:1.Mark the direction of rotation of the flywheel. Always rotate only in clockwise

direction when viewing in front of the flywheel.2.Mark the Bottom Dead Center (BDC) position on the flywheel with the reference

point when the piston reaches the lowermost position during rotation of the

flywheel.

3.Mark the Top Dead Center (TDC) position on the flywheel with the referencepoint when the piston reaches the top most position during the rotation of

flywheel.

4.Identify the four strokes by the rotation of the flywheel and observe themovement of inlet and exhaust valves.

5. Mark the opening and closing events of the inlet and exhaust valves on the

flywheel.

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6. Measure the circumferential distance of the above events either from TDC or

from BDC whichever is nearer and calculate their respective angles.7. Draw the valve timing diagram and indicate the valve opening and closing

periods.

FORMULA:L

Angle = ----- 3600

X

Where,

L - Distance from nearest dead center in mm

X - Circumference of the Flywheel in mm

OBSERVATIONS:

Sl. No. Description Distance in mm Angles in

Degrees

1. IVO Before TDC

2. IVC After BDC

3. EVO Before BDC

4. EVC After TDC

RESULT:The given four-stroke compressed ignition engine is studied and the valve timing diagram

is drawn for the present set of values.

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EXPERIMENT NO. 5

AIM:To conduct a performance test on the two stage reciprocating air compressorand to determine the volumetric efficiency and isothermal efficiencies at

various delivery pressures.

APPARATUS REQUIRED:

1. Reciprocating air compressor test rig.

2. Manometer3. Tachometer

SPECIFICATIONS:Power :

Type : Two stage reciprocating

Cooling Medium : Air

Capacity :

Maximum Pressure :Speed :

BRIEF THEORY OF THE EXPERIMENT:

The two stage reciprocating compressor consists of a cylinder, piston, inlet and exit

valves which is powered by a motor. Air is sucked from atmosphere and compressed inthe first cylinder (Low pressure) and passed to the second cylinder (High pressure)

through an inter cooler. In the second cylinder, air is compressed to high pressure and

stored in the air tank. During the downward motion of the piston, the pressure inside thecylinder drops below the atmospheric pressure and the inlet valve is opened due to the

pressure difference. Air enters into the cylinder till the piston reaches the bottom dead

center and as the piston starts moving upwards, the inlet valve is closed and the pressure

starts increasing continuously until the pressure inside the cylinder above the pressure ofthe delivery side which is connected to the receiver tank. Then the delivery valve opens

and air is delivered to the air tank till the TDC is reached. At the end of the delivery

stroke a small volume of high pressure air is left in the clearance volume. Air at highpressure in the clearance volume starts expanding as the piston starts moving downwards

up to the atmospheric pressure and falls below as piston moves downward. Thus the

cycle is repeated. The suction, compression and delivery of air take place in two strokes /one revolution of the crank

PRECAUTIONS:

1. The orifice should never be closed so as to prevent the manometer fluid beingsucked in to the tank.

2. At the end of the experiment the outlet valve of the reservoir should be opened asthe compressor is to be started against at low pressures so as to prevent excess

strain on the piston.

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EXPERIMENTAL SETUP:

The two-stage air compressor consists of two cylinders of v type. The compressor isdriven by an AC motor. Air is first sucked into the low pressure (LP) cylinder and it is

compressed and delivered at some intermediate pressure. The compressed air is then

cooled in the intercooler and the same is then sucked by the high pressure (HP) cylinder.

Compressed air is the finally discharged to the receiver tank.An orifice plate is mounted on one side of the air tank and which is connected with a

manometer for the measurement of air flow rate. One side of the air tank is attached with

a flexible rubber sheet to prevent damage due to pulsating air flow. A pressure gauge ismounted on the air tank to measure the air tank pressure. The tank pressure can be

regulated by adjusting the delivery valve. A pressure switch is mounted on the air tank to

switch off the motor power supply automatically when the pressure inside the tank raisesto the higher limit and to avoids explosion.

PROCEDURE:

1. The manometer is checked for water level in the limbs.

2. The delivery valve in the receiver tank is closed.3. The compressor is started and allowed to build up pressure in the receiver tank.

4. Open and adjust the outlet valve slowly to maintain the receiver tank pressure constant.5. The dynamometer is adjusted so that the circular balance reads zero when the points at

the motor pedestal coincide. This can be done by operating the hand wheel.

6. Note down the readings as per the observation table.

7. Repeat the experiment for various delivery pressures. This can be done by closing thedelivery valve and running the compressor to build up higher pressure. Ensure the tank

pressure is maintained constant by adjusting the outlet valve before taking the readings.

8. Tabulate the values and calculate the volumetric efficiency and isothermal efficiency.

OBSERVATION TABLE:

Sl.No Deliverypressure

(Kgf /cm2)

Manometer Reading(mm)

Speed TorqueKg.m

h1 h2 h1 - h2 Motor Comp.

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CALCULATION:

h1- h2 w1. Hair = ------------ ------- m

100 air

Where,

Hair = Air head causing the flow, m

h1, h2 = Manometer reading, mmw = Density of water = 1000kg/m

3

air = Density of air, kg/m3

Paair = ---------------- kg/m

3

RT

Where,

Pa = Atmospheric pressure

R = Gas constant for air = 0.287 KJ/Kg.KT = Room temperature K

2. Va = Cd A (2gHair) m3/s

Where,

Va = Actual volume of air compressed m3/s

Cd = Coefficient of discharge =

A = area of orifice = (/4) d2

d = diameter of orifice = m

Va

3. V1 = ------------ TNTP m3/s

TRTPWhere,

V1 = Actual volume of air compressed at NTP m3/s

Va = Actual volume of air compressed m3/sTNTP = 273 K

TRTP = 273 + Room temperature in K

D2 L Nc

4. V2 = ---------------------------- m3/s4 60

Where,

V2 = Theoretical volume of air compressed m3/s

D = Diameter of cylinder = mL = Stroke length = m

NC = Speed of the compressor

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V15. V.E. = ----------- 100 %

V2Where,

V.E = Volumetric efficiencyV1 = Actual volume of air compressed at NTP m3/s

V2 = Theoretical volume of air compressed m3/s

ln (r) Pa Va

6. I.P. = ------------------------------ KW1000

Where,

Iso.P = Isothermal Power

Pa + Pg

r = -------------------Pa

r = Compression ratioPa = Atmospheric pressure N/m2 ( 1.01325 x 105 N/m2)

Pg = Pressure in the tank N/m2 (Pressure gauge reading x 105)

35 2 Nm ( T 9.81)7. I.P. = ------ ------------------------------ motor KW

30 60000Where,

I.P. = Input Power

Nm = Motor speed rpm

T = Torque on the motor Kg.mmotor =

Iso. P.

8. I.E = ---------------- 100

I.P.

Where,I.E. = Isothermal Efficiency

Iso.P. = Isothermal Power

I.P. = Input Power

GRAPH:

1. Gauge pressure Vs Volumetric efficiency

2. Gauge pressure Vs Isothermal efficiency

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RESULT:

The performance test on the given air compressor test rig is conducted and the volumetricand isothermal efficiencies are determined at various delivery pressures and the

characteristic curves are drawn.

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EXPERIMENT NO. 6

AIM:- To prepare variable speed performances test on a four-Stroke, four-

Cylinder Petrol Engine and prepare the curves: (i) BP, BSFC, BMEP,

Torque Vs Speed and (ii) Volumetric Efficiency & A/F Ratio Vs Speed.

APPARATUS USED :-

Four-Stroke, four-Cylinder Petrol Engine Test Rig, Stop Watch, and Digital

Tachometer.

THEORY :-

S.I. Engines are often used for automotive purposes. It is important to know thetorque, brake mean effective pressure, and specific fuel consumption over the

engine working speed range. For this purpose variable speed test at full load and

part load is conducted. To test the park ignition engine at full load the throttle valve

is kept wide open and the brake load is adjusted to obtain the lowest desired speed.

The ignition timing may be set to obtain maximum output at this speed. Rate of fuelconsumption, dynamometer load reading and speed are recorded.

FORMULE USED:-

(i) Torque,

T = 9.81 x W x Reffective N-m.; Where Reffective= (D + d)/2 or (D + t)/2 m, and

W (Load) = ( S1- S2) Kg,

(ii) Brake Power,B P = ( 2N T ) / 60, 000 KW

; Where N = rpm, T= Torque N-m,

(iii)Indicated Power,

IP = n (Pm Lstroke A N ) / 60,000 KW

; Pm = Mean effective pressure N/m2

Lstroke = stroke m, A( cross section of the cylinder) = D2 /4 m2

N = N/2 (four stroke)

(i) Fuel Consumption,

mf= ( 50 ml x 10-6 x fuel) / ( t ) kg/s

Here; 1 ml = 10-3

liters, and 1000 liters = 1 m3

So 1 ml = 10-6

m3

(V) Brake Mean Effective Pressure,BMEP = ( BP x 60,000)/ Lstrokex A x N N/m

2

Lstroke= stroke m, A( cross section of the cylinder) = D2 /4 m2


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(vi) Brake Specific Fuel Consumption,BSFC = ( mfx 3600 ) / B P Kg/ KW . hr

(vii) Indicated Specific Fuel Consumption,ISFC = ( mfx 3600 ) / I P Kg/ KW .hr

(viii) Indicated Thermal Efficiency,= ( I P x 100 ) / (mfx C.V. ) %

(ix) Brake Thermal Efficiency,

= ( B P x 100 ) / (mfx C.V. ) %

(X) Mass of the air, mair = Cd x Ao g h airwater kg/sWhere Cd(coefficient of discharge) = , air = (pa x 10

2)/ (R x Ta ) kg/m

3,

Ao(area of orifice) = ( do2)/4 m

2, P1 = 1.10325 bar , R = 0.287 KJ/Kg.K,

Ta = ( ta + 273 ) K, ta = Ambient temperatureoC

(XI) Air fuel ratio, A/F = (mair / mfuel ) Kg/Kg of fuel

(XII) Volumetric efficiency, = (Vair x 100 )/ Vs %; where Vair ( volume of air inhaled/sec) = ( mair/air ) m

3/sec.

Vs (swept volume /sec) = n. (Lstroke A N) /60 m3/sec

(XIII) Mechanical efficiency , BP/IP

PROCEDURE:-

1. Before starting the engine check the fuel supply, 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. Note down the fuelconsumption rate.

5. Adjust the dynamometer to the new value of the desired speed. Note and record the

data as in step 4

6. Repeat the experiment for various speeds up to the rated speed of the engine.7. Do the necessary calculations.

OBSERVATIONS:-

No. of Cylinders, n =Brake Drum Diameter, D =

Rope Diameter, d =

Bore, Dbore =Stroke, Lstroke =Engine Displacement, Vswept =

Engine Horse Power, BHP =

Density of fuel (Petrol), fuel =Density of Manometer fluid, water =Calorific value of fuel (Petrol), C.V. = KJ/ Kg

Orifice Diameter, do =

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Co-efficient of Discharge, Cd =

Ambient Temperature, ta =Atmospheric Pressure, Pa = 1.01325 Bar

OBSERVATIONS TABLE :-

Sl.

No.

Engine speed

,

N(rpm)

Dynamometer spring

balance

Reading, (Kg)

Time taken for 50

ml

Fuel , t (sec)

Manometer

Reading

S1 (kg) S2 (kg)

CALCULATION:

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RESULT TABLE:

Sl.

No.

Engine

speed,

N(rpm)

Torque

(N-m)

Brake

Power,

BP

(KW)

Air

consumption

Rate, mair

(kg/hr)

Fuel

Consumption

Rate, mf

(kg/hr)

BSFC

(kg/KW.hr)

BMEP

(N/m2)

A/F

ratio

Mecha.

Efficien

%age

1.

2.

3.

4.

RESULTS:-

Performance curves are plotted and they are similar to the standard performance Curves

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EXPERIMENT NO. 7

AIM:- To prepare variable speed performances test on a four-Stroke, four-

Cylinder Diesel Engine and prepare the curves: (i) BP, BSFC, BMEP,

Torque Vs Speed and (ii) Volumetric Efficiency & A/F Ratio Vs Speed.

APPARATUS USED :-

Four-Stroke, four-Cylinder Diesel Engine Test Rig, Stop Watch, and Digital

Tachometer.

THEORY :-

In the diesel engine, air is compressed adiabatically with a compression ratio typicallybetween 15 and 20. This compression raises the temperature to the ignition temperature

of the fuel mixture which is formed by injecting fuel once the air is compressed.

Diesel fuel is used in C.I engines which is less volatile than gasoline, and will only ignite

under severe pressure and/or very high temperatures. That makes diesel fuel safer to

handle, and reduces the chance of a fire or explosion should the fuel tank rupture in acrash.

Diesels produce large amounts of torque (pulling power) at low engine speeds; a smallfour-cylinder diesel can easily produce as much torque as a larger six-cylinder gasoline

engine. This strong mid-range torque gives diesel cars excellent passing power.

Horsepower ratings for diesels tend to be lower, because horsepower is a function of

speed and diesels tend to have a lower redline (maximum operating speed) than gasolineengines.

FORMULE USED:-

(i) Torque,T = 9.81 x W x R

effectiveN-m.

; Where Reffective= (D + d)/2 or (D + t)/2 m, andW (Load) = ( S1- S2) Kg,


; Where N = rpm, T= Torque N-m,(iv)Indicated Power,

IP = n (Pm Lstroke A N ) / 60,000 KW

; Pm = Mean effective pressure N/m2

Lstroke = stroke m, A( cross section of the cylinder) = D2 /4 m2


(ii)Fuel Consumption,mf= ( 50 ml x 10

-6 x fuel) / ( t ) kg/s

Here; 1 ml = 10-3

liters, and 1000 liters = 1 m3

So 1 ml = 10-6 m3

(V) Brake Mean Effective Pressure,

BMEP = ( BP x 60,000)/ Lstrokex A x N N/m2

Lstroke= stroke m, A( cross section of the cylinder) = D2 /4 m2

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(vi) Brake Specific Fuel Consumption,BSFC = ( mfx 3600 ) / B P Kg/ KW . hr

(vii) Indicated Specific Fuel Consumption,ISFC = ( mfx 3600 ) / I P Kg/ KW .hr

(viii) Indicated Thermal Efficiency,= ( I P x 100 ) / (mfx C.V. ) %

(ix) Brake Thermal Efficiency,= ( B P x 100 ) / (mfx C.V. ) %

(X) Mass of the air, mair = Cd x Ao g h airwater kg/sWhere Cd(coefficient of discharge) = , air = (pa x 10

2 )/ (R x Ta ) kg/m3,

Ao(area of orifice) = ( do2)/4 m2, P1 = 1.10325 bar , R = 0.287 KJ/Kg.K,


(XI) Air fuel ratio, A/F = (mair / mfuel ) Kg/Kg of fuel

(XII) Volumetric efficiency, = (Vair x 100 )/ Vs %

; where Vair ( volume of air inhaled/sec) = ( mair/air ) m3/sec.

Vs (swept volume /sec) = n. (Lstroke A N) /60 m3/sec

(XIII) Mechanical efficiency , BP/IP

PROCEDURE:-1. Before starting the engine check the fuel supply, 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. Note down the fuel

consumption rate.

5. Adjust the dynamometer to the new value of the desired speed. Note and record the

data as in step 46. Repeat the experiment for various speeds up to the rated speed of the engine.

7. Do the necessary calculations.

OBSERVATIONS:-No. of Cylinders, n =

Brake Drum Diameter, D =Rope Diameter, d =Bore, Dbore =

Stroke, Lstroke =

Engine Displacement, Vswept =Engine Horse Power, BHP =

Density of fuel (Petrol), fuel =Density of Manometer fluid, water =

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Calorific value of fuel (Petrol), C.V. = KJ/ Kg

Orifice Diameter, do =Co-efficient of Discharge, Cd =

Ambient Temperature, ta =

Atmospheric Pressure, Pa = 1.01325 Bar


Sl.

No.

Engine speed

,

N(rpm)

Dynamometer spring

balance

Reading, (Kg)

Time taken for 50

ml

Fuel , t (sec)

Manometer

Reading

S1 (kg) S2 (kg)

CALCULATION:

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RESULT TABLE:

Sl.

No.

Engine

speed,

N(rpm)

Torque

(N-m)

Brake

Power,

BP

(KW)

Air

consumption

Rate, mair

(kg/hr)

Fuel

Consumption

Rate, mf

(kg/hr)

BSFC

(kg/KW.hr)

BMEP

(N/m2)

A/F

ratio

Mecha.

Efficien

%age

1.

2.

3.

4.

RESULTS:-

Performance curves are plotted and they are similar to the standard performance Curves

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EXPERIMENT NO. 8

AIM:- To prepare heat balance sheet on four-Cylinder petrol Engine.

APPARATUS USED :-

1.

Multi-Cylinder Petrol Engine Test Rig2. Rig, Stop Watch and Digital Tachometer.

THEORY:-

The thermal energy produced by the combustion of fuel in an engine is not completely

utilized for the production of the mechanical power. The thermal efficiency of I. C.Engines is about 33 %. Of the available heat energy in the fuel, about 1/3 is lost through

the exhaust system, and 1/3 is absorbed and dissipated by the cooling system.

It is the purpose of heat balance sheet to know the heat energy distribution, that is, how

and where the input energy from the fuel is is distributed. The heat balance sheet of an I.C. Engine includes the following heat distributions:

a. Heat energy available from the fuel brunt.b. Heat energy equivalent to output brake power.

c. Heat energy lost to engine cooling water.

d. Heat energy carried away by the exhaust gases.

e. Unaccounted heat energy loss.

FORMULE USED :-

(i) Torque,


W (Load) = ( S1- S2) Kg,



(iii)Fuel Consumption,

mf= ( 50 ml x 10-6 x fuel) / ( t ) kg/s

Here; 1 ml = 10-3 liters, and 1000 liters = 1 m3

So 1 ml = 10-6 m3

(iv) Heat energy available from the fuel brunt,

Qs = mfx C. V. x 3600 KJ/hr

(v) Heat energy equivalent to output brake power,

QBP = BP x 3600 KJ/hr

(vi) Heat energy lost to engine cooling water,

QCW = mW x CW (tWOtWI ) x 3600 KJ/hr

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(vii) Heat energy carried away by the exhaust gases,

QEG = mfg x Cfg (tfgtair )x 3600 KJ/hr

; where mfg = ( mf+ mair ) kg/s, and mair = Cd Ao g h airwater kg/s

Where Cd(coefficient of discharge) = 0.6, air = (pa x 102 )/ (R x Ta ) kg/m

3,

Ao(area of orifice) = ( do2)/4 m

2, P1 = 1.10325 bar , R = 0.287 KJ/Kg.K,


(viii) Unaccounted heat energy loss

Qunaccounted = Qs{ QBP + QCW + QEG } KJ/hr

PROCEDURE :-

1. Before starting the engine check the fuel supply, lubrication oil, and availability

of cooling water.2. Set the dynamometer to zero load and run the engine till it attain the working

temperature and steady state condition.

3. Note down the fuel consumption rate, Engine cooling water flow rate, inlet and

outlet temperature of the engine cooling water, Exhaust gases cooling water flow

rate, Air flow rate, and Air inlet temperature.

4. Set the dynamometer to 20 % of the full load, till it attains the steady state

condition. Note down the fuel consumption rate, Engine cooling water flow rate,

inlet and outlet temperature of the engine cooling water, Exhaust gases cooling

water flow rate, Air flow rate, and Air inlet temperature.

5. Repeat the experiment at 40 %, 60 %, and 80 % of the full load at constant

speed.

6. Disengage the dynamometer and stop the engine.

7. Do the necessary calculation and prepare th e heat balance sheet.

OBSERVATIONS:-

Engine Speed, N = rpm

No. of Cylinders, n = four

Calorific Value of Fuel, C.V. = KJ/Kg

Specific Heat of Water, C = 4.187 KJ/Kg . K wSpecific Heat of Exhaust Flue Gases, Cfg = 2.1 KJ/Kg . K

Gas Constant, R = 0.287 KJ/Kg . K

Ambient Temperature, ta =oC


Orifice Diameter, do = m

Co-efficient of Discharge, C =

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Density of fuel (diesel) , fuel = kg/m3

Density of water , water = kg/m3

Brake drum diameter, D = m

Rope diameter ,d = m

Belt thickness, tbelt= m


Sl.

No.

Engine

speed

N

(rpm)

Dynamometer

Spring

Balance Readings,

(Kg)

Time

taken for

50 ml

fuel,

t (sec)

Engine

cooling

Water

Flow

rate,

mw

(kg/hr)

Engine cooling

Water tem (oC)

Exhaust

Gas

Temp

tfg (o

C)

Mano

meter

Readi

ngtwi

(0C)

Two

(oC)

S1 (kg) S2 (kg)

1.

2.

3.

4.

CALCULATIONS:-

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RESULT TABLE:

SL.

No.

Engine

speed

Brake

power

BP(KW)

Fuel

consumption,

mf( kg/ hr)

Air flow

rate

mair (kg/hr)

Exhaust gas flow

rate,

mfg (kg/hr)

1.

2.

3.

4.

HEAT BALANCE SHEET:

Heat

energy

supplied

KJ/hr %

age

Heat energy consumed

( Distribution)

KJ/hr % age

Heat

energy

Available

From the

fuel

Burnt

(a)Heat energy equivalentto output brake power

(b)Heat energy lost toengine cooling water

(c)Heat energy carriedaway

By the exhaust gases.

(d)Unaccounted heatEnergy loss.

Total --------- 100% Total ------------ 100%

RESULT:

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EXPERIMENT NO. 9

AIM:- To prepare heat balance sheet on four-Cylinder diesel Engine.

APPARATUS USED :-

1.

Multi-Cylinder diesel Engine Test Rig2. Rig, Stop Watch and Digital Tachometer.

THEORY:-

The thermal energy produced by the combustion of fuel in an engine is not completely

utilized for the production of the mechanical power. The thermal efficiency of I. C.Engines is about 33 %. Of the available heat energy in the fuel, about 1/3 is lost through

the exhaust system, and 1/3 is absorbed and dissipated by the cooling system.

It is the purpose of heat balance sheet to know the heat energy distribution, that is, how

and where the input energy from the fuel is is distributed. The heat balance sheet of an I.C. Engine includes the following heat distributions:

a. Heat energy available from the fuel brunt.b. Heat energy equivalent to output brake power.

c. Heat energy lost to engine cooling water.

d. Heat energy carried away by the exhaust gases.

e. Unaccounted heat energy loss.

FORMULE USED :-

(i) Torque,


W (Load) = ( S1- S2) Kg,



(iv)Fuel Consumption,

mf= ( 50 ml x 10-6 x fuel) / ( t ) kg/s

Here; 1 ml = 10-3 liters, and 1000 liters = 1 m3

So 1 ml = 10-6 m3

(iv) Heat energy available from the fuel brunt,

Qs = mfx C. V. x 3600 KJ/hr

(v) Heat energy equivalent to output brake power,

QBP = BP x 3600 KJ/hr

(vi) Heat energy lost to engine cooling water,

QCW = mW x CW (tWOtWI ) x 3600 KJ/hr

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(vii) Heat energy carried away by the exhaust gases,

QEG = mfg x Cfg (tfgtair )x 3600 KJ/hr

; where mfg = ( mf+ mair ) kg/s, and mair = Cd Ao g h airwater kg/s

Where Cd (coefficient of discharge) = , air = (pa x 102 )/ (R x Ta )

kg/m3,

Ao(area of orifice) = ( do2)/4 m2, P1 = 1.10325 bar , R = 0.287

KJ/Kg.K,


(viii) Unaccounted heat energy loss

Qunaccounted = Qs{ QBP + QCW + QEG } KJ/hr

PROCEDURE :-

1. Before starting the engine check the fuel supply, lubrication oil, and availability

of cooling water.

2. Set the dynamometer to zero load and run the engine till it attain the working

temperature and steady state condition.

3. Note down the fuel consumption rate, Engine cooling water flow rate, inlet and

outlet temperature of the engine cooling water, Exhaust gases cooling water flow

rate, Air flow rate, and Air inlet temperature.

4. Set the dynamometer to 20 % of the full load, till it attains the steady state

condition. Note down the fuel consumption rate, Engine cooling water flow rate,

inlet and outlet temperature of the engine cooling water, Exhaust gases cooling

water flow rate, Air flow rate, and Air inlet temperature.

5. Repeat the experiment at 40 %, 60 %, and 80 % of the full load at constant speed.

6. Disengage the dynamometer and stop the engine.

7. Do the necessary calculation and prepare th e heat balance sheet.

OBSERVATIONS:-


No. of Cylinders, n = four

Calorific Value of Fuel, C.V. = KJ/KgSpecific Heat of Water, C = 4.187 KJ/Kg . K w

Specific Heat of Exhaust Flue Gases, Cfg = 2.1 KJ/Kg . K

Gas Constant, R = 0.287 KJ/Kg . K

Ambient Temperature, ta =oC


Orifice Diameter, do = m

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Co-efficient of Discharge, C =

Density of fuel (diesel) , fuel = kg/m3

Density of water , water = kg/m3

Brake drum diameter, D = m

Rope diameter ,d = m

Belt thickness, tbelt= m


Sl.

No.

Engine

speed

N

(rpm)

Dynamometer

Spring

Balance Readings,

(Kg)

Time

taken for

50 ml

fuel,

t (sec)

Engine

cooling

Water

Flow

rate,

mw

(kg/hr)

Engine cooling

Water tem (oC)

Exhaust

Gas

Temp

tfg (o

C)

Manom

eter

Readingtwi

(0C)

Two

(oC)

S1 (kg) S2 (kg)

1.

2.

3.

4.

CALCULATIONS:-

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RESULT TABLE:

SL.

No.

Engine

speed

Brake

power

BP(KW)

Fuel

consumption,

mf( kg/ hr)

Air flow

rate

mair (kg/hr)

Exhaust gas flow

rate,

mfg (kg/hr)

1.

2.

3.

4.

HEAT BALANCE SHEET:

Heat

energy

supplied

KJ/hr %

age

Heat energy consumed

( Distribution)

KJ/hr % age

Heat

energy

Available

From the

fuel

Burnt

(e)Heat energy equivalentto output brake power

(f) Heat energy lost toengine cooling water

(g)Heat energy carriedaway

By the exhaust gases.

(h)Unaccounted heatEnergy loss.

Total --------- 100% Total ------------ 100%

RESULT:

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EXPERIMENT NO. 10

AIM: To find the indicated power (IP) on Multi-Cylinder Petrol Engine by Morse

test.

APPARATUS USED: -

1. Multi-Cylinder Petrol Engine Test Rig2. Stop Watch,3. Hand Gloves4. Digital Tachometer.

THEORY :-

The purpose of Morse Test is to obtain the approximate Indicated Power of a Multi-

cylinder Engine. It consists of running the engine against a dynamometer at a particularspeed, cutting out the firing of each cylinder in turn and noting the fall in BP each time

while maintaining the speed constant. When one cylinder is cut off, power developed isreduced and speed of engine falls.Accordingly the load on the dynamometer is adjusted so as to restore the engine speed.

This is done to maintain FP constant, which is considered to be independent of the load

and proportional to the engine speed. The observed difference in BP between all

cylinders firing and with one cylinder cut off is the IP of the cut off cylinder. Summationof IP of all the cylinders would then give the total IP of the engine under test.

FORMULE USED :-

(v)Brake Power, BP = WN/ C KW; Where W =Load on the Dynamometer Kg, N = rpm of the Engine,and C =Dynamometer Constant.

(ii) Indicated Power ( IP ) of each Cylinders:IP1 = ( BPTBP234) KWIP2= (BPTBP134) KWIP3 = (BPTBP124) KWIP4 = (BPTBP123) KW

(iii) Total IP of the Engine,

IP = (IP1 +IP2 + IP3 + IP4 ) KW(iv) Mechanical efficiency,

= BPT / IPT

PROCEDURE:-

1. Before starting the engine check the fuel supply, lubrication oil, and availability of

cooling water.

2. Set the dynamometer to zero load.

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3. Run the engine till it attains the working temperature and steady state condition. Adjust

the dynamometer load to obtain the desired engine speed. Record this engine speedand dynamometer reading for the BP calculation.

4. Now cut off one cylinder. Short-circuiting its spark plug can do this.

5. Reduce the dynamo meter load so as to restore the engine speed as at step 3. Record

the dynamometer reading for BP calculation.6. Connect the cut off cylinder and run the engine on all cylinders for a short time. This

is necessary 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.

OBSERVATIONS:-


No. of Cylinders, n = Four

Calorific Value of Fuel, C.V. = KJ/Kg


Sl. No. Cylinders

Working

Dynamometer

Reading, (KW)

Brake

Power, BP

(KW)

IP of the cut

off

cylinder,

(KW)

1. 1-2-3-4 ------------------- BPT =

2. 2-3-4 BP234= IP1=

3. 1-3-4 BP134= IP2=

4. 1-2-4 BP124= IP3=

5. 1-2-3 BP123= IP4=

CALCULATIONS:-

RESULT:-

Total IP of the Multi-Cylinder Petrol Engine by Morse Test, IPT = KW

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EXPERIMENT NO. 11

AIM: To find the flash and fire point of the given fuel / oil by cleave land open cup

apparatus.

APPARATUS REQUIRED:

1. Open cup tester

2. Thermometer (0300C)3. Sample of fuel / oil

4. Splinter sticks

DESCRIPTION OF THE EQUIPMENT:

This apparatus consists of a cylindrical cup of standard size. It is held in place in themetallic holder that is placed on a wire gauge and is heated by means of an electric heater

housed inside the metallic holder.

A provision is made on the top edge of the cup to hold the thermometer in position. A

standard filling mark has been scribed on the inner side of the cup and the sample oil isfilled up to this mark. This apparatus is more accurate than Pensky Martons closed cupand it gives sufficiently proclaimed accurate result for most of the practical purposes.

PROCEDURE:

1. Fill the cleaned open cup with the given sample of oil up to the standard fillingmark of the cup.

2. Insert the thermometer in the holder on the top edge of the cup. Make sure thatthe bulb of the thermometer is immersed in the oil and should not touch the

metallic part.3. Heat the sample of fuel / oil by means of an electric heater so that the sample of

oil gives out vapour at the rate of 10 C per minute.

4. When the oil gives out vapours, start to introducing the glowing splinter ( theflame should not touch the oil ) and watch for any flash with flickering sound.

5. Blow out or expel the burnt vapour before introducing the next glowing splinter.This ensures that always fresh vapours alone is left over the surface of the oil and

the test is carried out accurately.

6. Continue the process of heating and placing the glowing splinter at every tendegree of rise in temperature from the first flash till you hear the peak flickering

sound and note the corresponding temperature as the flash point.

7. Continue the heating further after retaining the flash point and watch the firepoint, which is noted when the body of the oil vapour ignites and continue to burn

at least for five seconds.

8. Repeat the test twice or thrice with fresh sample of the same oil until the resultsare equal.

9. Tabulate the observations.

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OBSERVATION TABLE:

Sl.No. Temperature( C ) Observations

RESULT:The flash and fire point test is carried out and the following oil / fuel properties

are found.

The flash point of the given sample fuel / oil is =

The fire point of the given sample fuel / oil is =

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EXPERIMENT No.-12

AIM :-To study the Locomotive Boilers and Babcock & Wilcox Boilers.

APPARATUS USED :- Model of Locomotive and Babcock & Wilcox Boilers.

THEORY :-

A closed vessel in which steam is produced from water by combustion of fuel. According

to A.S.M.E, combustion of apparatus for producing or recovering heat together with theapparatus for transferring the heat so made available to the fluid being heated and

vaporized.The primary requirements of steam generator or boiler are:1. Water

2. Water drum

3. Fuel for heating

TYPES OF BOILERS :-a. Water tube boiler b. Fire tube boiler

In the water tube boilers, the water are inside the tube & hot gases surrounds the tubes.The various water tube boiler are following :

(i) Babcock & Wilcox boiler

(ii) Sterling boiler

(iii) Lamont boiler(iv) Loeffler boiler

(v) Benson boiler

(vi) Velox boilerThe various fire tube boiler are following :

(i) Lancashire boiler

(ii) Locomotive boiler

(iii) Scotch marine(iv) Cochran boiler

LOCOMOTIVE BOILERS

Locomotive boiler is a horizontal multi tubular, natural circulation, artificial draft, internally

fired, fire tube boiler; Locomotive boilers are manufactured in both portable or mobile and

stationary types. A locomotive boiler produces steam upto to pressure of 25 bar and the steaming

rate as high as 55 to 75 kg per square meter of the heating surface per hour upto 7000 kg per hour.

Locomotive boilers are designed to meet the sudden and fluctuating demands of steam due tovariation in power output. Locomotive boilers are used in railway engines, road rollers and

haulage engines. They are also used in stationary service power plants where semi portability is

desired.

CONSTRUCTION OF LOCOMOTIVE BOILERS

The main parts of the Locomotive Boiler are fire box, boiler shell and smoke box. The firebox

which forms the furnace is constructed by extending the boiler shell downward from the sides at

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its rear end. The annular space left in between the furnace wall and downward extension of the

boiler shell is also connected with the water space in the barrel. The grate over which the fuel

burns is mounted sloping downwards in the furnace. Beneath the grate there is an ash pit for

collecting the ashes. The hot gases rising from the grate are deflected by the fire brick arch which

ensures more uniform and proper heating because the deflected hot gases come in contact with

the entire heating surface of the fire box.

The boiler barrel is a cylindrical shell and it accommodates a large number of flue tubes which

connect the furnace with the smoke box. The flue tubes are made of two sizes. Super heater tubes

are inserted into the large diameter flue tubes. The steam dome located at the top of the

cylindrical shell is meant to collect the dry steam. The smoke box is connected to the boiler barrel

at its front end. A super heater header which distributes the steam to the super heater tube is

mounted inside the smoke box. The chimney located at the top of the smoke box is made very

short in order to avoid its striking with the tunnels and under bridge when the locomotive passes

through the tunnels and below the under bridge. Since the chimney is short, its reduces the

draught. But the motion of the locomotive creates a strong artificial forced draft. In some

locomotive boilers artificial draught is also created by passing the exhaust steam from the engine

cylinder into the smoke box. Since the exhaust steam will be at low pressure, a pressure

differential will be set up between the smoke box and the fire box which causes the drawl of the

hot gases through the fire tubes and make their exit through the chimney. This causes the drawl of

air through the grate. The smoke box door provided at its front end facilitates cleaning inside the

smoke box.

WORKING OF LOCOMOTIVE BOILER

Water is filled nearly to three fourth of the barrel space so as to submerge completely the fire box

and the flue tubes, and also to fill the annular space left in between the furnace wall and the

downward extension of the boiler shell. The coil is charged into the furnace through the fire doorand burnt over the grate. The hot gases rising from the grate are deflected by the fire brick arch so

as to heat the entire fire box more uniformly, and then pass through the flue tubes from the

furnace to the smoke box. The heat is transferred from hot gases through the walls of the furnace

and also through the walls of the flue tubes. From the smoke box the hot gases escape through the

chimney. The steam evolving from the surface of the water is accumulated in the steam space and

also in the steam dome. Inside this steam dome there is a throttle valve connected to the main

steam pipe. This throttle valve is regulated by the regulating rod to allow the required quantity of

the steam to pass. For superheating the steam so as increase the thermal energy, the steam is

passed from the main steam pipe to the super heater header and then through the super heater

tubes which are in the bigger flue tubes. The steam passing through the super heater a tube is

further heated by the hot gases passing in the flue tubes and gets superheated. The superheated

steam from the super heater tubes are returned to the super heater header from there it is passed to

the steam engine cylinders.

BABCOCK & WILCOX BOILER :-

The water tube boilers are used exclusively, when pressure above 10bar and capacity inexcess of 7000kg./hr. is required.

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DIMENSION & SPECIFICATIONS :

Diameter of the drumLength of the drum

Size of the water tubes

Size of the super heater tubes

Working pressureSteaming capacity

Efficiency

CONSTRUCTION & WORKING :- Babcock & Wilcox boiler with longitudinal

drum

It consists of a drum connected to a series of front end and rear end header by short risertubes. To these headers are connected a series of inclined water tubes of solid drawn mild

steel. The inclination of tubes to the horizontal is about 15 degree or more. A hand hole is

provided in the header in front of each tube for cleaning & inspection of tubes. A feed

valve is provided to fill the drum and level of water indicates by water level indicator.

Fire is burnt on the grate. The hot gases are forced to move upwards between the tubes bybaffle plates provided. The water from the drum flows through the inclined tubes via

down take header & goes back into the steam the steam space of the drum. The steamthen enters through the anti- priming pipe and flows in the super heater tubes where it is

further heated and is finally taken out through the main stop valve and supplied to the

engine when needed.

In the cross drum there is no limitation of the number of connecting tubes. In case ofcross drum:

Pressure --------------------------

Steaming capacity --------------

APPLICATIONS :-

The steam generated is employed for the following purpose :

1. For generating power in steam engines or steam turbines.2. In the textile industries for sizing & bleaching etc. and many other industries like

sugar mills, chemical industries.

3. For heating the building in cold weather & for producing hot water supply.4. Steam turbine propelled ships and other marine vessels.

5. Agriculture field machineries, saw mills etc.

6. Steam locomotive.7. To study steam to the steam engine for driving industries hoists, road rollers, in road

constructions, pumps in coal mine.

PRECAUTIONS :-

Do not feed water fully the drum. Water level should be checked properly. Pressure should not be over the rating pressure. Clean the boiler time to time. Boiler operator should be present there.

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