me6412 thermal engineering laboratory manual – i

ME6412 THERMAL ENGINEERING LABORATORY I 2015

1 PREPARED BY C. BIBIN, AP/MECH, RMKCET

1. VALVE TIMING DIAGRAM OF FOUR STROKE

CYCLE PETROL ENGINE

Exp. No. : Date:

Aim :

To draw the valve timing diagram of the given four stroke cycle petrol engine.

Apparatus Required :

1. Four stroke petrol engine

2. Measuring tape

3. Chalk

4. Piece of paper.

5. Polar Graph

Theory and Description :

The diagram which shows the position of crank of four stroke engine at the

beginning and at the end of suction, compression, expansion and exhaust of the engine

are called as valve timing diagram.

The extreme position of the piston at the bottom of the cylinder is called Bottom

Dead Centre [BDC]. In the case of horizontal engine, this is known as Outer Dead

Center(ODC). The extreme position of the piston at the top of the cylinder is called

Top Dead Centre (TDC). In the case of horizontal engine this is known as Inner Dead

Centre (IDC).

Ideal Engine:

In an ideal engine, the inlet valve opens at TDC and close at BDC. The exhaust

valve opens at BDC and close at TDC. The charge is ignited when the piston is at TDC at

the end of compression stroke. But in actual practice it will differ.



Actual Engine:

Inlet valve opening and closing :

In an actual engine, the inlet valve begins to open few degrees before the piston

reaches the TDC during the exhaust stroke. This is necessary to ensure that the valve will

be fully open to allow the more amount of air fuel mixtures into the cylinder as soon as

the piston starts to move TDC during the suction stoke.

If the inlet valve is allowed to close at BDC, the cylinder would receive less

amount of air-fuel mixture than its capacity and the pressure of the mixture at the end of

suction stroke will be below, the atmosphere pressure. To avoid this, the inlet valve is

kept open for 400 to 50

0 rotation of the crank after the BDC for high speed engine and 20

0

to 250 for low speed engine.

Exhaust valve opening and closing :

Complete clearing of the burned gases from the cylinder is necessary to take in

more air-fuel mixtures into the cylinder and also to avoid the dilution of the fresh

mixture. To achieve this the exhaust valve is open at 250 to 45

0 before the piston reaches

the BDC during the power stroke.

In order to completely remove the burned products, the exhaust valve is remain

open for 50 to 10

0 after the TDC during the suction stroke.

For certain period both inlet valve and exhaust valve remains in open condition.

The crank angle for which the both the valves are open are called as over lapping. This

overlap must not be excessive enough to allow the burned gases to be checked into the

intake manifold or the fresh charge escape through the exhaust valve.

Ignition:

There is always a time between the spark and ignition of mixture. The ignition

starts some time after giving the spark, therefore it is necessary to produce the spark

before piston reaches the TDC to obtain proper combustion without losses. The angle

through which the spark is given earlier is known as Ignition Advantage or Angle of

Advance. It may ranges from 350to 40

0 before the piston reaches the TDC during the

compression stroke.



Observation

1. Circumference of flywheel = ................. cm

Formula used:

1. Crank angle = Distance of flywheel x 360

Circumference of flywheel

2. Time duration = Crank angle displacement

360 x Engine speed in sces

Tabulation

Sl.

No Event

Position of crank w.r.to

Nearest Dead centre

Distance from

their respective

dead centres in

cm

Angle in

degrees

1 IVO Before TDC

2 IVC After BDC

3 EVO Before BDC

4 EVC After TDC

5

IG

Before TDC

Model calculation:



Procedure:

1. Remove the cylinder head cover and identify the inlet valve exhaust valve and piston

of particular cylinder.

2. Mark the BDC and TDC position of flywheel. This is done by Rotating the crank in

the usual direction of rotation and observe the position of the fly wheel. When the

piston is moving downwards at which the piston, begins to move in opposite

direction. i.e from down to upward direction. Make the mark on the flywheel with

reference to fixed point on the body of the engine. That point is the BDC for that

cylinder. Measure the circumstance of the flywheel and mark the point from BDC at a

distance of half of the circumference. That point is TDC and is diametrically opposite

to the BDC.

3. Insert the paper in the tappet clearance of both inlet and exhaust valves.

4. Slowly rotate the crank until the paper in the tappet clearance of inlet valve is

gripped. Make the mark on fly wheel against fixed reference. This position represent

the inlet valve open (IVO). Measure the distance from TDC and tabulate the distance.

5. Rotate the crank further, till the paper is just free to move. Make the marking on the

flywheel against the fixed reference. This position represents the inlet valve close

(IVC). Measure the distance from BDC and tabulate the distance. Rotate the crank

further, till the paper in the tappet clearance of exhaust valve is gripped. Make the

marking on the flywheel against fixed reference. This position represents the exhaust

valve open (EVO). Measure the distance from BDC and tabulate.

6. Then convert the measured distances into angle in degrees

Result:

The valve timing diagram for the given four stroke Petrol engine was drawn.

Duration of suction stroke = ....................

Duration of compression stroke = ....................

Duration of expansion stroke = ....................

Duration of exhaust stroke = ....................



2. VALVE TIMING DIAGRAM OF FOUR STROKE CYCLE diesel ENGINE

Exp. No. : Date:

Aim :

To draw the valve timing diagram of the given four stroke cycle diesel engine.


1. Four stroke diesel engine

2. Measuring tape

3. Chalk

4. Piece of paper.

5. Polar Graph


The diagram which shows the position of the crank of four stroke engine at the

beginning and at the end of suction, compression, expansion and exhaust of the

engine are called as valve timing diagram.

The extreme position of the piston at the bottom of the cylinder is called

Bottom Dead Centre [BDC]. In the case of horizontal engine, this is known as

Outer Dead Center(ODC). The extreme position of the piston at the top of the

cylinder is called Top Dead Centre (TDC). In the case of horizontal engine this is

known as Inner Dead Centre (IDC).

Ideal Engine:

In an ideal engine, the inlet valve opens at TDC and close at BDC. The exhaust

valve opens at BDC and close at TDC. The fuel is ignited when the piston is at TDC at

the end of compression stroke. But in actual practice it will differ.



Actual Engine:

Inlet valve opening and closing :

In an actual engine, the inlet valve begins to open 50 to 20

0 before the piston

reaches the TDC during the exhaust stroke. This is necessary to ensure that the valve will

be fully open when the piston reaches the TDC. If the inlet valve is allowed to close at

BDC, the cylinder would receive less amount of air than its capacity and the pressure at

the end of suction will be below, the atmosphere pressure. To avoid this, the inlet valve is

kept open for 400 to 50

0 after the BDC.

Exhaust valve opening and closing :

Complete clearing of the burned gases from the cylinder is necessary to take in

more air into the cylinder. To achieve this the exhaust valve is open at 250 to 45

0 before

BDC and closes at 100 to 20

0 after the TDC. It is clear from the diagram, for certain

period both inlet valve and exhaust valve remains in open condition. The crank angles for

which the both valves are open are called as overlapping period. This overlapping is more

than the petrol engine.

Fuel valve opening and closing:

The fuel valve opens at 10 to 15 before TDC and closes at 15 to 20 after TDC.

This is because better evaporation and mixing fuel.

Procedure:

1. Remove the cylinder head cover and identify the inlet valve exhaust valve and

piston of particular cylinder.

2. Mark the BDC and TDC position of flywheel. This is done by Rotating the crank

in the usual direction of rotation and observe the position of the fly wheel. When

the piston is moving downwards at which the piston, begins to move in opposite

direction. i.e from down to upward direction. Make the mark on the flywheel with

reference to fixed point on the body of the engine. That point is the BDC for that

cylinder. Measure the circumstance of the flywheel and mark the point from BDC

at a distance of half of the circumference. That point is TDC and is diametrically

opposite to the BDC.



Observation

1. Circumference of flywheel (X ) = ................. cm

Formula used:


Circumferenc e of flywheel



Tabulation:

S.No Event Position of crank w.r.to

TDC or BDC

Distance from

their

respective

dead centres in

cm

Angle in

degrees

1 IVO Before TDC

2 IVC After BDC

3 EVO Before BDC

4 EVC After TDC

5 FVO Before TDC

6 FVC After TDC

Model calculation:



3. Insert the paper in the tappet clearance of both inlet and exhaust valves.

4. Slowly rotate the crank until the paper in the tappet clearance of inlet valve is

gripped. Make the mark on fly wheel against fixed reference. This position

represent the inlet valve open (IVO). Measure the distance from TDC and tabulate

the distance.

5. Rotate the crank further, till the paper is just free to move. Make the marking on

the flywheel against the fixed reference. This position represent the inlet valve

close (IVC). Measure the distance from BDC and tabulate the distance.

6. Rotate the crank further, till the paper in the tappet clearance of exhaust valve is

gripped. Make the marking on the flywheel against fixed reference. This position

represents the exhaust valve open (EVO). Measure the distance from BDC and

tabulate it.

7. Rotate the crank further, till the paper in the tappet clearance of exhaust valve is

just free to move. Making the marking on the flywheel against fixed reference.

This position represents the exhaust valve close (EVC). Measure the distance

from TDC and tabulate it.

8. Then convert the measured distances into angle in degrees.

Result:

The valve timing diagram for the given four stroke Diesel engine was drawn.

Duration of suction stroke = ....................

Duration of compression stroke = ....................

Duration of expansion stroke = ....................

Duration of exhaust stroke = ....................

Duration of valve overlap = ....................



3. port TIMING DIAGRAM OF two STROKE CYCLE petrol ENGINE

Exp. No. : Date:

Aim :

To draw the port timing diagram of the given two stroke cycle petrol engine.


1. Two stroke petrol engine

2. Measuring tape

3. Chalk

4. Polar Graph


In the case of two stroke cycle engines the inlet and exhaust valves are not

present. Instead, the slots are cut on the cylinder itself at different elevation and they are

called ports. There are three ports are present in the two stroke cycle engine.

1. Inlet port

2. Transfer port

3. Exhaust port

The diagram which shows the position of crank at which the above ports are open and

close are called as port timing diagram.

The extreme position of the piston at the bottom of the cylinder is called Bottom

Dead Center [BDC]. The extreme position of the piston at the top of the cylinder is

called Top Dead Centre [TDC].

In two stroke petrol engine the inlet port open when the piston moves from BDC

to TDC and is closed when the piston moves from TDC to BDC.



Observation

1. Circumference of flywheel (X ) = ................. cm

Formula used:


Circumference of flywheel



Tabulation:

S.No Event Position of crank w.r.to

TDC or BDC

Distance in

cm Angle in

degrees

1 IPO Before TDC

2 IPC After TDC

3 EPO Before BDC

4 EPC After BDC

5 TPO Before BDC

6 TPC After BDC

Model calculation:



The transfer port is opened when the piston is moves from TDC to BDC and the

fuel enters into the cylinder through this transport from the crank case of the engine. The

transfer port is closed when piston moves from BDC to TDC. The transfer port opening

and closing are measured with respect to the BDC.

The exhaust port is opened, when the piston moves from TDC to BDC and is

closed when piston moves from BDC to TDC. The exhaust port opening ad closing are

measured with respect to the BDC.

The transfer port is opened when the piston is moves from TDC to BDC and the

fuel enters into the cylinder through this transport from the crank case of the engine. The

transfer port is closed when piston moves from BDC to TDC. The transfer port opening

and closing are measured with respect to the BDC.

The exhaust port is opened, when the piston moves from TDC to BDC and is

closed when piston moves from BDC to TDC. The exhaust port opening ad closing are

measured with respect to the BDC.

Procedure :

1. Remove the ports cover and identify the three ports.

2. Make the TDC and BDC position on the fly wheel. To mark this position follow

the same procedure as followed in valve timing diagram.

3. Rotate the flywheel slowly in usual direction (usually clockwise) and observe the

movement of the position.

4. When the piston moves from BDC to TDC observe when the bottom edge of the

piston just uncover the bottom end of the inlet port. This is the inlet port opening

(IPO) condition, make the mark on the fly wheel and measure the distance from

TDC.

5. When piston moves from TDC to BDC observe, when the bottom edge of piston

completely covers the inlet port. This is the inlet port closing (IPC) condition.

Make the mark on the flywheel and measure the distance from TBDC.



6. When the piston moves from TDC to BDC, observe when the top edge of the

piston just uncover the exhaust port. This is the exhaust port opening [EPO]

condition. Make the mark on the flywheel and measure the distance from BDC.

7. When the piston moves from BDC to TDC, observe, when the piston completely

cover the exhaust port. This is the exhaust port closing condition [EPC]. Make the

mark on the flywheel and measure the distance from BDC.

8. When the piston moves from TDC to BDC, observe, when the top edge of the

piston just uncover the transfer port. This is the transfer port opening [TPO]

condition. Make the mark on the flywheel and measure the distance from BDC.

9. When the piston moves from BDC to TDC, observe, when the piston completely

covers the transfer port. This is the transfer port closing [TPC] condition. Make

the mark of the flywheel and measure the distance from BDC.

Note :

1. The inlet port opening distance and closing distance from TDC are equal.

2. The exhaust port opening distance and closing distance from BDC are equal.

3. The transfer port opening distance and closing distance from BDC are equal.

Result :

The port timing diagram for the given two stroke cycle petrol engine was drawn.



4. ACTUAL INDICATOR DIAGRAM FOR A FOUR STROKE CYCLE PETROL ENGINE

Exp. No. : Date:

Aim :

To study the actual indicator diagram for a four stroke cycle petrol engine.

Actual indicator diagram for a four stroke cycle petrol engine:

The actual indicator diagram for a four stroke cycle petrol engine is shown. The

suction stroke is shown by the line 1-2, which lies below the atmospheric pressure line.

This pressure difference, which makes the fuel-air mixture to flow into the engine

cylinder. The inlet valve offers some resistance to the incoming charge. That is why, the

charge cannot enter suddenly into the engine cylinder. As a result of this, pressure inside

the cylinder remains somewhat below the atmospheric pressure during the suction stroke.

The compression stroke is shown by the line 2-3, which shows that the inlet valve closes

(lVC) a little beyond 2 (i.e. BDC). At the end of this stroke, there is an increase in the

pressure inside the engine cylinder. Shortly before the end of compression stroke (i.e.

TDC), the charge is ignited (lGN) with the help of spark plug as shown in the figure. The

sparking suddenly increases pressure and temperature of the products of combustion. But

the volume, practically, remains constant as shown by the line 3-4. The expansion stroke

is shown by the line 4-5, in which the exit valve opens (EVO) a little before 5 (i.e. BDC).

Now the burnt gases are exhausted into the atmosphere through the exit valve. The

exhaust stroke is shown by the line 5-1, which lies above the atmospheric pressure line. It



is this pressure difference, which makes the burnt gases to flow out of the engine

cylinder. The exit valve offers some resistance to the outgoing burnt gases. That is why

the burnt gases cannot escape suddenly from the engine cylinder. As a result of this,

pressure inside the cylinder remains somewhat above the atmospheric pressure line

during the exhaust stroke

Result:

Thus the actual indicator diagram for a four stroke cycle petrol engine was

studied.



5. ACTUAL INDICATOR DIAGRAM FOR A FOUR STROKE CYCLE diesel ENGINE

Exp. No. : Date:

Aim :

To study the actual indicator diagram for a four stroke cycle diesel engine.

Actual indicator diagram for a four stroke cycle diesel engine:

The actual indicator diagram for a four-stroke cycle diesel engine is shown. The

suction stroke is shown by the line 1-2 which lies below the atmospheric pressure line.

This pressure difference, which makes the fresh air to flow into the engine cylinder. The

inlet valve offers some resistance to the incoming air. That is why, the air cannot enter

suddenly into the engine cylinder. As a result of this pressure inside the cylinder remains

somewhat below the atmospheric pressure during the suction stroke. The compression

stroke is shown by the line 2-3, which shows that the inlet valves closes (IVC) a little

beyond 2 (i.e. BDC).At the end of this stroke, there is an increase of pressure inside the

engine cylinder. Shortly before the end of compression stroke (i.e. TDC), fuel valve

opens (FVO) and the fuel is injected into the engine cylinder. The fuel is ignited. Actual

indicator diagram for a by high temperature of the compressed air. The ignition suddenly

increases volume and temperature of the products of combustion. But the pressure,

practically, remains constant as shown by the line 3-4. The expansion stroke is shown by

the line 4-5, in which the exit valve opens a little before 5 (i.e. BDC). Now the burnt

gases are exhausted into the atmosphere through the exhaust valve. The exhaust stroke is

shown by the line 5-1, which lies above the atmospheric pressure line. It is this pressure

difference, which makes the burnt gases to flow out of the engine cylinder. The exhaust

valve offers some resistance to the outgoing burnt gases. That is why, the burnt gases

cannot (escape suddenly from the engine cylinder). As a result of this, pressure inside the

cylinder remains somewhat above the atmospheric pressure during the exhaust stroke.



Result:

Thus the actual indicator diagram for a four stroke cycle diesel engine was

studied.



6. ACTUAL INDICATOR DIAGRAM FOR A two STROKE CYCLE petrol ENGINE

Exp. No. : Date:

Aim :

To study the actual indicator diagram for a two stroke cycle petrol engine.

Actual Indicator Diagram For A Two Stroke Cycle Petrol Engine:

The actual indicator diagram for a two-stroke cycle petrol engine is shown in

suction is shown by the line 1-2-3, i.e. from the instant transfer port opens (TPO) and

transfer port closes (TPC). We know that during the suction stage, the exhaust port is also

open. In the first half of suction stage, the volume of fuel-air mixture and burnt gases

increases. This happens as the piston moves from I to 2 (i.e. BDC). In the second half of

the suction stage, the volume of charge and burnt gases decreases. This happens as the

piston moves upwards from 2 to 3. A little beyond 3, the exhaust port closes (EPC) at 4.

Now the charge inside the engine cylinder is compressed which is shown by the line 4-5.

At the end of the compression, there is an increase in the pressure inside the engine

cylinder. Shortly before the end of compression (i.e. TDC) the charge is ignited (IGN)

with the help of spark plug. The sparking suddenly increases pressure and temperature of

the products of combustion. But the volume, practically, remains constant as shown by

the line 5-6. The expansion is shown by the line 6-7. Now the exhaust port opens (EPO)

at 7, and the burnt gases are exhausted into the atmosphere through the exhaust port. It

reduces the pressure. As the piston is moving towards BDC, therefore volume of burnt

gases increases from 7 to 1. At 1, the transfer port opens (TPO) and the suction starts.



Result:

Thus the actual indicator diagram for a two stroke cycle petrol engine was

studied.



7. ACTUAL INDICATOR DIAGRAM FOR A two STROKE CYCLE diesel ENGINE

Exp. No. : Date:

Aim :

To study the actual indicator diagram for a two stroke cycle diesel engine.

Actual Indicator Diagram For A Two Stroke Cycle Diesel Engine:

The actual indicator diagram for a two-stroke cycle diesel engine is shown. The

suction is shown by the line: 1-2-3 i.e. from the instant transfer port opens (TPO) and

transfer port closes (TPC). We know that during the suction stage, the exhaust port is also

open. In the first half of suction stage, the volume: of air and burnt gases increases. This

happens as :the piston moves from 1-2 (i.e. BDC). In the second half of the suction stage,

the volume of air and burnt gases decreases. This happens as the piston moves upwards

from 2-3. A little beyond 3, the exhaust port closes (EPC) at 4. Now the air inside the

engine cylinder is compressed which is shown by the line 4-5. At the end of compression,

there is an increase in the pressure inside the engine cylinder. Shortly before the end of

compression (i. e. TDC), fuel valve opens (FVO) and the fuel is injected into the engine

cylinder. The fuel is ignited by high temperature of the compressed air. The ignition

suddenly increases volume and temperature of the products of combustion. But the

pressure, practically, remains constant as shown by the line 5-6. The expansion IS shown

by the line 6-7, Now the exhaust port opens (EPO) at 7 and the burnt gases are exhausted

into the atmosphere through the exhaust port. It reduces the pressure. As the piston is

moving towards BDC, therefore volume of burnt gases increases from 7 to 1. At 1, the

transfer port opens (TPO) and the suction starts.



Result:

Thus the actual indicator diagram for a two stroke cycle diesel engine was

studied.



8. PERFORMANCE TEST ON FOUR STROKE

SINGLE CYLINDER AIR COOLED DIESEL ENGINE

Exp. No. : Date:

Aim :

The experiment is conducted to

a. To study and understand the performance characteristics of the engine.

b. To draw Performance curves.

Apparatus Required:

1. Single cylinder Diesel Engine

2. Tachometers

3. Stop watch

4. Temperature indicators

Theory:

A machine, which uses heat energy obtained from combustion of fuel and

converts it into mechanical energy, is known as a Heat Engine. They are classified as

External and Internal Combustion Engine. In an External Combustion Engine,

combustion takes place outside the cylinder and the heat generated from the combustion

of the fuel is transferred to the working fluid which is then expanded to develop the

power. An Internal Combustion Engine is one where combustion of the fuel takes place

inside the cylinder and converts heat energy into mechanical energy. IC engines may be

classified based on the working cycle, thermodynamic cycle, speed, fuel, cooling, method

of ignition, mounting of engine cylinder and application.

Diesel Engine is an internal combustion engine, which uses heavy oil or diesel oil

as a fuel and operates on two or four stroke. In a 4-stroke Diesel engine, the working

cycle takes place in two revolutions of the crankshaft or 4 strokes of the piston. In this

engine, pure air is sucked to the engine and the fuel is injected with the combustion

taking place at the end of the compression stroke. The power developed and the

performance of the engine depends on the condition of operation. So it is necessary to test

an engine for different conditions based on the requirement.



Specification:

Engine:

Make : Kirloskar

Number of cylinder : 1

Bore : 87.5 mm

Stroke : 80 mm

Cubic capacity : 0.662 litres

Compression Ratio : 17.5:1

Power : 4.41 Kw

Cooling Type : Air cooled

Fuel : Diesel

Calorific Value of fuel : 44800 KJ/Kg

Density of fuel :..Kg/m3

Load:

Type : Rope Brake

Diameter of brake drum : 300 mm

Range : 0-25 Kg

Load Indicator : Dial gauge

Diameter of the Rope : .mm

CC Tube:

Range : 0-100 CC

Material : Glass

Air Drum:

Size : 400 X 400 X 400 mm

Inlet Diameter : 10 mm

Outlet Diameter : 25.4 mm

Thermocouple:

Type : K

Range : Alumel / Chromal

Material : 2000C



Manometer:

Range : 0 240 mm

Manometer Liquid : Mercury

Temperature Indicator

Type : Digital

Channel : 1

Thermocouple : K

Input : 230 V / 50 Hz

Formula Used:

1.Effective Brake Radius ...m..........2

dD=R

Where

D- Brake wheel diameter in metres

d - Rope diameter in metres

2.Torque mR.......N.W=T

Where

W - Effective Brake Load in Newtons

R - Effective Brake Radius in metres

3.Brake Power KWX

NT=BP ..............

100060

2

Where

N - Engine Speed in rpm

T - Torque in Nm

4.Total fuel consumption sKgt

XX=mTFC f /..........

1010)(

6

Where

- Density of fuel in Kg/m3

t- Time taken for 10 cc of fuel consumption in seconds.

5.Indicated Power = BP+FP ...............Kw

Where



BP - Brake Power in Kilowatts.

FP - Frictional Power in Kilowatts.(by Willan's line Method)

6.Mechanical Efficiency 100%IP

BP=mech

Where


IP - Indicated Power in Kilowatts.

7.Heat Supplied Kwm

=Qf

s ..............CV3600

Where

mf - Mass of fuel consumed in Kg/s

CV - Calorific Value of fuel in KJ/Kg = 44800 KJ/Kg

8.Indicated thermal Efficiency 100%s

ITQ

IP=

Where

Qs - Heat Supplied in Kilowatts.


9.Brake thermal Efficiency 100%s

BTQ

BP=

Where



10.Brake Specific Fuel Consumption hrKWKgXBP

m=BSFC

f./..........3600

Where



11.Indicated Specific Fuel Consumption hrKWKgXIP

m=ISFC

f./..........3600

Where





Procedure:

1. Before starting the engine check the fuel supply and lubricating oil level.

2. Check the water supply

3. Crank the engine by hand lever and start

4. Allow the engine to reach steady state condition

5. Supply water to brake drum and adjust the flow

6. At no load condition note down the following readings

Time taken for 10cc of fuel consumption

Load indicated on dial gauge

Speed of the engine using tachometer.

7. Apply the load, then note down the mentioned.

8. Repeat the procedure at different load conditions

9. Calculate the performance of an engine.

10. Repeat the experiment for different loads and note down the above readings.

11. After the completion release the load and then switch of the engine.

12. Allow the water to flow for few minutes and then turn it off.

Precautions:

1. Do not run the engine if supply voltage is less than 180V

2. Do not run the engine without the supply of water.

3. Supply water free from dust to prevent blockage in rotameters, engine head and

calorimeter.

4. Note that the range for water supply provided is an approximate standard values,

however the user may select the operating range to his convenience not less than 3 & 2

LPM for engine and calorimeter respectively.

5. Do not forget to give electrical earth and neutral connections correctly.

6. It is recommended to run the engine at 1500 rpm otherwise the rotating parts and

bearing of engine may run out.



Graph:

The following graphs are drawn by taking Brake power on X-axis and other

variable parameters on Y-axis.

Brake power Vs Total fuel consumption

Brake power Vs Specific fuel consumption

Brake power Vs Brake thermal efficiency

Brake power Vs Indicated thermal efficiency

Brake power Vs Mechanical efficiency

Result:

The performance of a given engine was tested and mechanical efficiency was

found and graphs are drawn



9. Heat balance test on SINGLE CYLINDER

AIR COOLED DIESEL ENGINE

Aim:-

To conduct a heat balance test and prepare heat balance sheet on Single-Cylinder

Diesel Engine.

Apparatus Required:

1. Given IC engine with loading arrangement 2. Measuring tape or Thread and scale

3. Tachometer

4. Stop watch

5. Bucket

6. Spring balance

7. Temperature indicator

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 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.



Formula Used:


dD=R

Where




Where



3.Brake Power KWX

NT=BP ..............

100060

2

Where


T - Torque in Nm

4.Total fuel consumption sKgt

XX=mTFC f /..........

1010)(

6

Where

- Density of fuel in Kg/m3

t- Time taken for 10 cc of fuel consumption in seconds.

5.Heat energy available from the fuel brunt, Kwm

=Qf

s ..............CV3600

Where

mf - Mass of fuel consumed in Kg/s

CV - Calorific Value of fuel in KJ/Kg

6.Heat energy equivalent to output brake power, QBP = BP x 3600 KJ/hr

7.Heat carried away by the exhaust gases (Qg )= mg CPg (Tg TR )



mg = mass of the exhaust gases in kg/s

ma = mass of air consumed in kg/s

mf = mass of fuel consumed in kg/s

Cpg = Specific heat of exhaust gases

= 1.005 KJ/kgK

Tg = Temperature of exhaust gases in C

TR = Room temperature in C

8.Mass of the exhaust gases (mg) = ma + mf . kg/s

9.Mass of air supplied sKgQ=m aaa /...............

Where

Qa- Volume of air supplied in m3/s

a Density of air in kg/m3

10.Pressure Head mXH

=H ma

wa ..........

Where

Hw- Difference in manometer reading

a Density of air in kg/m3 = 1.164 Kg/m3

m Density of water in kg/m3 = 13000 Kg/m3

11.Volume of air consumed sm2gHaa

aaC=Q ada /........

. 32

2

2

1

21

Where

a1 - Cross sectional area of pipe in m2

a2 - Cross sectional area of Orifice in m2

g Acceleration due to gravity in m/s2

12.Cross sectional area of pipe

2

114

d=a

...................... m2

Where

d1 Diameter of pipe in metres = 25.4 mm

13.Cross sectional area of Orifice

2

224

d=a

...................... m2

Where

d2 Diameter of Orifice in metres = 10 mm



14.Heat energy carried away by the exhaust gases, QEG = mg x Cpg (tg ta) Kw

15.Unaccounted heat energy loss, QUnaccounted = Qs { QBP + QEG } KJ/hr

ta = Ambient Temperature o

C

Procedure:

1. From the name plate details, calculate the maximum load that can be applied

on the given engine.

2. Check the engine for fuel availability , lubricant and cooling water connection

3. Release the load on engine completely and start the engine with no load

condition. Allow the engine to run for few minute to attain the rated speed

4. Adjust the cooling water flow and maintain steady flow of water.

5. Apply the load, from no load to required load slowly. At required load slowly.

At required load note the following.

i) Load on the engine

ii) Speed of the engine in Rpm

iii) Time taken for 10 cc of fuel consumption

iv) Manometer readings

v) Temperature of cooling water at engine inlet and engine outlet in

C

vi) Room temperature and temperature of exhaust gases



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, Exhaust gases 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 the heat balance sheet.

Result:-

The heat balance test was completed and heat balance sheet was drawn.



10. load test, performance test and

Heat balance test on SINGLE CYLINDER

AIR COOLED DIESEL ENGINE using data

acquisition system

Ex. No: Date:

Aim:

To conduct load test, performance test and heat balance test on four stroke single

cylinder air cooled diesel engine using data acquisition system.

Apparatus Required:

1. Engine with load

2. Computer with data acquisition

3. Data acquisition system cable

Specification:

Engine:

Make : Kirloskar

Number of cylinder : 1

Bore : 87.5 mm

Stroke : 80 mm

Cubic capacity : 0.662 litres

Compression Ratio : 17.5:1

Power : 4.41 Kw

Cooling Type : Air cooled



Fuel : Diesel

Calorific Value of fuel : 44800 KJ/Kg

Density of fuel :..Kg/m3

Load:

Type : Rope Brake

Diameter of brake drum : 300 mm

Range : 0-25 Kg

Load Indicator : Dial gauge

Diameter of the Rope : .mm

CC Tube:

Range : 0-100 CC

Material : Glass

Air Drum:

Size : 400 X 400 X 400 mm

Inlet Diameter : 10 mm

Outlet Diameter : 25.4 mm

Thermocouple:

Type : K

Range : Alumel / Chromal

Material : 2000C

Manometer:

Range : 0 240 mm

Manometer Liquid : Mercury

Temperature Indicator

Type : Digital

Channel : 1

Thermocouple : K

Input : 230 V / 50 Hz



Procedure:

1. Before the start of the engine, check the fuel supply electrical supply and

lubricating oil level

2. Crank the engine by hand lever and start.


4. Switch on the data acquisition system.

5. Open data acquisition software on computer

6. Now click connect icon on the main window then click start icon.

7. Values will display on main window

8. Close the fuel tank value now engine take fuel from cc tube.

9. When fuel level decreases beyond high level sensor timer in the window starts.

10. When fuel level decreases beyond low level sensor time stops.

11. Each time when reading taken wait until the fuel consumption clock stops.

12. At no load condition after timer stopper takes the reading by clicking read icon

13. After reading taken open the fuel tank value to fill the fuel in cc tube.

14. When fuel level reaches high level sensor timer in window reset.

15. Now click start icon to read the values in engine.

16. Apply load on engine.

17. Wait till fuel consumption clock stops.

18. Now read the values displayed on the computer by clicking read.

19. Repeat the procedure at different load condition.

20. Now click the calculation icon. A new window will open in that window enter

radius of arm and click show.

21. Click graph icon a new window will appear



Graph:








Result:

Thus load test, performance test and heat balance are done on four stroke single

cylinder air cooled diesel engine using data acquisition system.




Heat balance test on three CYLINDER

water cooled petrol ENGINE using data

acquisition system

Ex. No: Date:

Aim:

To conduct load test, performance test and heat balance test on four stroke three

cylinder water cooled petrol engine using data acquisition system.

Apparatus Required:

1. Engine with load



Procedure:

1. 1. Before the start of the engine, check the fuel supply electrical supply and

























Graph:








Result:

Thus load test, performance test and heat balance are done on three cylinder water

cooled petrol engine using data acquisition system.




Heat balance test on single CYLINDER

water cooled diesel ENGINE using data

acquisition system

Ex. No: Date:

Aim:


cylinder water cooled diesel engine using data acquisition system.

Apparatus Required:

1. Engine with load



Procedure:


























Graph:








Result:


cylinder water cooled diesel engine using data acquisition system.




Heat balance test on single CYLINDER

air cooled petrol ENGINE using data

acquisition system

Ex. No: Date:

Aim:


cylinder air cooled petrol engine using data acquisition system.

Apparatus Required:

1. Engine with load



Procedure:


























Graph:








Result:


cylinder air cooled petrol engine using data acquisition system.



10. MORSE TEST ON four stroke three

CYLINDER PETROL ENGINE

Ex. No: Date:

Aim:

To conduct mores test on given multi cylinder petrol engine in order to determine

the indicated power developed in the each cylinder of the engine and to determine the

mechanical efficiency.

Apparatus Required:

1. Multi cylinder petrol engine with ignition cut off arrangement

2. Loading arrangements

3. Tachometer

Theory and Description:

For slow speed engine the indicated power is directly calculated from the

indicator diagram. But in modern high speed engines, it is difficult to obtain accurate

indicator diagram due to inertia forces, and therefore, this method cannot be applied. In

such cases the mores test can be used to measure the indicated power and mechanical

efficiency of multi cylinder engines. The engines test is carried out as follows. The

engine is run at maximum load at certain speed. The B.P is then measured when all

cylinders are working.

Then one cylinder is made in operative by cutting off the ignition to that cylinder.

As a result of this the speed of the engine will decrease. Therefore, the load on the engine

is reduced so that the engine speed is restored to its initial value. The assumption made

on the test is that frictional power is depends on the speed and not upon the load on the

engine.



Formula used:


dD=R

Where




Where



3.Brake Power KWX

NT=BP ..............

100060

2

Where


T - Torque in Nm

4. Indicated Power ( IP ) of each Cylinders:

IP1 = ( BP BP1) KW

IP2 = ( BP BP2) KW

IP3 = ( BP BP3) KW

5.Total IP of the Engine, IP = ( IP1 + IP2 + IP3) KW

6.Mechanical Efficiency, mech = BP / IP

Observation and Tabulation:

(1) Brake power B.P =........... KW

(2) Rated Speed N =...........Rpm

(3) Type of loading : =...........

(4) Radius of brake drum : R =........... m

(5) Radius of Rope r = =........... m

(6) Number of cylinders =

Note: The speed should be same for all readings



Procedure:

1. From the name plate details, determine the maximum load that can be given to the

engine

2. Check the engine for fuel availability, lubricant and cooling water connections.

3. Release the load completely on the engine and start the engine in no load

conditions and allow the engine to run for few minutes to attain the rated speed.

4. Apply the load and increase the load up to maximum load. (All four cylinders

should be in working). Now note the load on the engine and speed of the engine

say the speed is N rpm

5. Cut-off the ignition of first cylinder, Now the speed of engine decreased. Reduce

the load on the engine and bring the speed of the engine to N rpm. Now note the

load on the engine.

6. Bring the all three cylinders are in working conditions and cut off the 2nd and 3rd

cylinder in turn and adjust the load to maintain same N rpm and note the load .

Result:

Morse test was conducted on given petrol engine and indicated power developed

in each cylinder is determined and mechanical efficiency is also determined.



15. DETERMINATION OF FLASH AND FIRE POINT

Exp. No. : Date:

Aim :

To determine the flash and fire point temperatures of the given sample of

lubricating oil using pensky martens apparatus.

Apparatus Required:

1. Pensky-martens apparatus

2. Electric heater

3. Thermometer

4. Bunsen Burner

Principle:

Flash point is the lowest temperature at which the lubricating oil gives off enough

vapors that ignite for a moment when tiny flame is brought near it.

Fire point is the lowest temperature at which the vapors of the oil burn

continuously for at least five seconds when a tiny flame is brought near it.

Significance:

Flash and fire points are used to indicate

Fire hazard of petroleum products and evaporation loses under high

temperature loses

It gives us the idea about the maximum temperature below which the oil can

be used

It is used as the means of identification of specific lubricating oil

For detection of contamination in the given lubricating oil

Description of Pensky Martens apparatus:

It is used to determine the flash point of the lubricating oils, fuel oils, solvents,

solvent containing material and suspension of solids. It consists of three parts



a) Oil Cup

Material- Brass

Height 5.5cm

Diameter-5cm

Lid of the cup is provided with four openings of standard sizes, first opening is for

stirrer, second is for admission of air, third is for thermometer and fourth is for

introducing test flame

b) Shutter

At the top of the cup shutter is provided. By moving the shutter, opening in the lid

opens and flame is dipped in to this opening, bringing the flame over the oil surface. As

the test flame is introduced in the opening, it get extinguished, but when the test flame is

returned to its original position, it is automatically lightened by the pilot burner

c) Stove

It consists of

1. Air bath,

2. Top plate on which the flange of the cup rest

Procedure:

1. Clean and dry all parts of the apparatus with the help of suitable solvent e.g. CCl4,

ether, petroleum spirit

or benzene and dry it to remove any traces of solvent.

2. Fill the oil cup with the test oil up to the mark.

3. Fix the lids on the top through which are inserted a thermometer and a stirrer. Ensure

that the flame exposure device is fixed on the top.

4. Light the test flame and adjust it to about 4 mm in diameter.

5. Heat apparatus as temp. of oil increases by 5 to 60

per min. as stirrer is continuously rotated.

6. At every 10 C rise of temp. Introduce test flame into the oil vapor. This is done by

operating the shutter. On moving knob of shutter, test flame is lowered in oil vapors

through opening.



Tabulation:

S.No Temperature of oil

in 0C Flash point temp

fire point temp



7. When test flame causes a distinct flame in interior cup, note temp. which represent the

flash point

8. Further heat the oil at the rate of 10C/ min. and continue applying the test flame as

before.

9. The temperature at which the vapors of the oil give a clear and distinct blue flash for

five seconds is recorded as the fire point of the oil.

Precautions:

1. The apparatus should be thoroughly dried. There should be no trace of moisture inside

the cup.

2. The thermometer bulb should dip into the oil.

3. While applying the test flame, stirring should be continued.

4. Fill the sample of the lubricating oil up to the mark. There should be no oil on the outer

part of the cup.

5. Avoid breathing over the surface of the oil.

Before starting the experiment

1. Ensure that the cup is clean from unwanted makes

2. Carbon deposits to be removed completely.

After starting

1. Ensure that there is no air bubble in the cup.

2. Care should be taken that the operator does not breath near the cup.

When stopping

1. Hot fuel should be carefully transferred from the cup to the breaker before

stopping.

2. Ensure that the flame and Bunsen burner.

3. Ensure that the workplace and apparatus are clean.

Result:

The flash and fire point temperatures of the given sample of oil was determined

by using pensky-martens apparatus.

The flash point temperature of the given sample of oil is 0C

The fire point temperature of the given sample of oil is 0C



16. SIMPLE VERTICAL BOILER

Exp. No. : Date:

Aim: -

To study about the construction, working and application of simple vertical boiler.

Construction: -

Figure shows the simplest form of an internally fired vertical fire-tube boiler. It

does not require heavy foundation and requires very small floor area.

Cylindrical shell:

The shell is vertical and it attached to the bottom of the furnace. Greater portion

of the shell is full of water which surrounds the furnace also. Remaining portion is steam

space. The shell may be of about 1.25 meters diameter and 2.0 meters height.

Cross-tubes:

One or more cross tubes are either riveted or flanged to the furnace to increase the

heating surface and to improve the water circulation.

Furnace (or fire box):

Combustion of coal takes place in the furnace (fire box).

Grate:

It is placed at the bottom of fire box and coal is fed on it for burning.

Fire door:

Coal is fed to the grate through the fire door.

Chimney (or stack):

The chimney (stack) passes from the top of the firebox through the top of the

shell.

Manhole:

It is provided on the top of the shell to enable a man to enter into it and inspect

and repair the boiler from inside it. It is also, meant for cleaning the interior of the boiler

shell and exterior of the combustion chamber and stack (chimney).



Hand holes:

These are provided in the shell opposite to the ends of each cross tube for

cleaning the cross tube.

Ash pit:

It is provide for collecting the ash deposit, which can be removed away at

intervals.

Theory:

The fuel (coal) is fed into the grate through the fire hole and is burnt. The ash pit

placed below the grate collect the ashes of the burning fuel. The combustion gas flows

from the furnace, passes around the cross tubes and escapes to the atmosphere through

the chimney. Water goes by natural circulation due to convection currents, from the

lower end of the cross tube and comes out from the higher end. The working pressure of

the simple vertical boiler does not exceed 70 N/cm2.

Working of simple vertical boiler:

In a simple vertical boiler fuel is added through the fire hake into the grate which

burn there to produce the hot gases. Fuel when converted into ash is collected into the ash

pit. Hot gases rise above and pass their heat to the water in the cross box and go out of

the boiler through the chimney. Water heats up and steam production starts. Steam which

produce as a result of water heating is collected at the steam space of the boiler. Steam is

collected until a certain pressure is attained and then steam is passed out for use like

running turbine or engine.

Application of simple vertical boiler:

Simple vertical boiler have may application is railway locomotives for example

railway steam engine Simple vertical boiler are used in the road vehicles like steam

wagon (steam lorry or steam wagon) Simple vertical boiler have a very famous

application that steam tractor There are number of boats specially smaller one which

uses the simple vertical boiler to power the engine In some parts of the world simple



vertical boiler are used in steam donkeys Simple vertical boilers are also used in the

steam cranes and steam shovels.

Advantages of simple vertical boiler:

low initial cost because of lesser parts

Low maintenance cost

Simple working

Easy to install and replace

Occupy small space on ground

Simple vertical boiler have water level tolerance

Disadvantages of simple vertical boiler:

Vertical design limits its working in many places Because of the limited grate

area steam production is limited Impurities settle down at the bottom thus prevent water

from heating Boiler tubes must be kept short to minimise height. As a result, much of the

available heat is lost through the chimney, as it has too little time to heat the tubes.

Result:

Thus the construction, working and application of simple vertical boiler was

studied.



17. COCHRAN BOILER

Exp. No. : Date:

Aim: -

To study about the construction, working and application of cochran boiler.

Theory: -

Cochran boiler is a vertical, multitubular, internally fired, fired, fire tube boiler. It

is a low pressure, medium capacity boiler. The maximum capacity of cochran boiler is

about 4000 kg of steam per hour and the maximum pressure of steam produced is about

10 bat. It mainly consists of a cylindrical shell with hemispherical crown, fire box, grate,

combustion chamber, smoke box and chimney for connecting pressure gauge, water

gauge, safety valve, steam stop value, fusible plug.

The boiler is filled with water to the specified level using a feed pump. The feed

check valve permits the feed water to entire into the boiler, but does not allow water to

flow back. Coal is fed into the grate through the fire hole and burnt. Ash formed is

collected in the provided below the grate and is removed. The hot gases from the firebox

pass through the flue pipe to the combustion chamber. From the combustion chamber the

hot gases pass through the horizontal flue tubes to smoke box. The gases from the smoke

box are discharged to the atmosphere through the chimney. Smoke box is provided with a

door for cleaning the flue tubes and smoke box. The hot gases while passing through the

flue tubes transfer heat to the water which is already heated by the fire box. The water

gets converted into steam and accumulates in the steam space at the top of the shell. This

steam is taken to the steam supply pipe through the steam stop valve.

Working:

The fuel is burnt on the grate and ash is collected and disposed of from ash pit.

The gases of combustion produced by burning of fuel enter the combustion chamber

through the flue tube and strike against fire brick lining which directs them to pass

through number of horizontal tubes, being surrounded by water. After which the gases

escape to the atmosphere through smoke box and chimney.



Construction:

Cochran boiler consists of a cylindrical shell with a dome shaped top where the

space is provided for steam. The furnace is one piece construction and is seamless. Its

crown has a hemispherical shape and thus provides maximum volume of space.

Characteristics:

1. Vertical Boiler

2. Multi tube Boiler

3. straight tube Boiler

4. low pressure Boiler

5. Coal fired Boiler

6. Single tube Boiler

7. Natural draft Boiler

8. Natural circulation Boiler

9. Stationary Boiler

10. internally fired Boiler

11. Water tube Boiler

Advantages:

The minimum floor area is required.

Cost of construction is low.

It can be moved and stet up take it to different location.

Boiler has self contained furnace. No brick work setting is necessary.

Any type of flue can be used.

Disadvantages:

Steam raising capacity is less due to vertical design.

Difficult in cleaning and inspection due to vertical design.

The capacity and pressure are limited.

The boiler requires high head room.

Result:

Thus the construction, working and application of Cochran boiler was studied.



18. BABCOCK-WILCOX BOILER

Exp. No. : Date:

Aim:

To study about the construction, working and application of Babcock-Wilcox

boiler

Theory:

Evaporating the water at appropriate temperatures and pressures in boilers does

the generation of steam. A boiler is defined as a set of units, combined together

consisting of an apparatus for producing and recovering heat by igniting certain fuel,

together with arrangement for transferring heat so as to make it available to water, which

could be heated and vaporized to steam form. One of the important types of boilers is

Babcock-Wilcox boiler.

Observation:

In thermal powerhouses, Babcock Wilcox boilers do generation of steam in large

quantities.

The boiler consists essentially of three parts.

1. A number of inclined water tubes: They extend all over the furnace. Water circulates

through them and is heated.

2. A horizontal stream and water drum: Here steam separate from the water which is

kept circulating through the tubes and drum.

3. Combustion chambers: The whole of space where water tubes are laid is divided into

three separate chambers, connected to each other so that hot gases pass from one to the

other and give out heat in each chamber gradually. Thus the first chamber is the hottest

and the last one is at the lowest temperature. The Water tubes 76.2 to 109 mm in diameter

are connected with each other and with the drum by vertical passages at each end called

headers. Tubes are inclined in such a way that they slope down towards the back. The

rear header is called the down-take header and the front header is called the uptake

header has been represented in the fig as DC and VH respectively.



Whole of the assembly of tubes is hung along with the drum in a room made of

masonry work, lined with fire bricks. This room is divided into three compartments A, B,

and C as shown in fig, so that first of all, the hot gases rise in A and go down in B, again

rises up in C, and then the led to the chimney through the smoke chamber C.

A mud collector M is attached to the rear and lowest point of the boiler into which the

sediment i.e. suspended impurities of water are collected due to gravity, during its

passage through the down take header.

Below the front uptake header is situated the grate of the furnace, either

automatically or manually fired depending upon the size of the boiler. The direction of

hot gases is maintained upwards by the baffles L. In the steam and water drum the steam

is separated from the water and the remaining water travels to the back end of the drum

and descends through the down take header where it is subjected to the action of fire of

which the temperature goes on increasing towards the uptake header. Then it enters the

drum where the separation occurs and similar process continuous further.

For the purpose of super heating the stream addition sets of tubes of U-shape

fixed horizontally, are fitted in the chamber between the water tubes and the drum. The

steam passes from the steam face of the drum downwards into the super heater entering at

its upper part, and spreads towards the bottom .Finally the steam enters the water box W,

at the bottom in a super heated condition from where it is taken out through the outlet

pipes.

The boiler is fitted with the usual mountings like main stop valve M, safety valve

S, and feed valve F, and pressure gauge P. Main stop valve is used to regulate flow of

steam from the boiler, to steam pipe or from one steam one steam pipe to other.

The function of safety valve is used to safe guard the boiler from the hazard of pressures

higher than the design value. They automatically discharge steam from the boiler if inside

pressure exceeds design-specified limit.

Feed check valve is used to control the supply of water to the boiler and to

prevent the escaping of water from boiler due to high pressure inside. Pressure gauge is

an instrument, which record the inside pressure of the boiler.

When steam is raised from a cold boiler, an arrangement is provided for flooding

the super heater. By this arrangement the super heater is filled with the water up to the



level. Any steam is formed while the super heater is flooded is delivered to the drum

ultimately when it is raised to the working pressure. Now the water is drained off from

the super heater through the cock provided for this purpose, and then steam is let in for

super heating purposes.

Result:

Thus the construction, working and application of Babcock Wilcox boiler was

studied.



19. LANCASHIRE BOILER

Exp. No. : Date:

Aim:

To study about the construction, working and application of Lancashire boiler.

Theory:

Evaporating the water at appropriate temperatures and pressures in boilers does

the generation of system. A boiler is defined as a set of units, combined together

consisting of an apparatus for producing and recovering heat by igniting certain fuel,

together with arrangement for transferring heat so as to make it available to water, which

could be heated and vaporized to steam form. One of the important types of boilers is

Lancashire boiler.

Observation:

Lancashire boiler has two large diameter tubes called flues, through which the hot

gases pass. The water filled in the main shell is heated from within around the flues and

also from bottom and sides of the shell, with the help of other masonry ducts constructed

in the boiler as described below.

The main boiler shell is of about 1.85 to 2.75 m in diameter and about 8 m long.

Two large tubes of 75 to 105 cm diameter pass from end to end through this shell. These

are called flues. Each flue is proved with a fire door and a grate on the front end. The

shell is placed in a placed in a masonry structure which forms the external flues through

which, also, hot gases pass and thus the boiler shell also forms a part of the heating

surface.



SS is the boiler shell enclosing the main flue tubes. SF are the side flues running

along the length of the shell and BF is the bottom flue. Side and bottom flues are the

ducts, which are provided in masonry itself. The draught in this boiler is produced by

chimney. The hot gases starting from the grate travel all along the flues tubes; and thus

transmits heat through the surface of the flues. On reaching at the back end of the boiler

they go down through a passage, they heat water through the lower portion of the main

water shell. On reaching again at front end they bifurcate to the side flues and travel in

the forward direction till finally they reach in the smoke chamber from where they pass

onto chimney. During passage through the side flues also they provide heat to the water

through a part of the main shell. Thus it will be seen that sufficient amount of area is

provided as heating surface by the flue tubes and by a large portion of the shell operating

the dampers L placed at the exit of the flues may regulate the flow of the gases. Suitable

firebricks line the flues. The boiler is equipped with suitable firebricks line the flues. The

boiler is equipped with suitable mountings and accessories.

There is a special advantage possessed by such types of boilers. The products of

combustion are carried through the bottom flues only after they have passed through the

main flue tubes, hence the hottest portion does not lie in the bottom of the boiler, where

the sediment contained in water as impurities is likely to fall. Therefore there are less

chances of unduly heating the plates at the bottom due to these sediments.

Result:

Thus the construction, working and application of Lancashire boiler was studied.



20. La Mont boiler

Exp. No. : Date:

Aim: -

To study about the construction, working advantages and disadvantages of La

Mont boiler

Construction: -

La Mont boiler is vertical boiler. It has two types of evaporator namely convective

evaporator and radiant evaporator. Radiant evaporator are mounted as near as

possible to the combustion chamber. The economizer is also used in La Mont boiler

to heat the feed water from flue gases. This heated water passed to evaporating drum.

At the top of the boiler air preheater is installed to heat the air which is required for

combustion in combustion chamber.

Working: -

The feed water from hot well is supplied to a storage and separating drum through

the economizer. The most of the sensible heat is supplied to the feed water passing

through the economizer. A centrifugal pump circulates the water equal to 8 to 10

times the weight of steam evaporated. This water is circulated through the evaporator

tubes and part of the water evaporated is separated in the separator drum. The large

quantity of water circulated prevents the tubes from being overheated.

The centrifugal pump delivers the feed water to the headers at pressure of 2.5

bars above the drum pressure. The distribution header distributes the water through

the nozzle into the evaporator. The steam separated in the boiler is further passed

through the superheater and then supplied to the turbine.

The air drawn by the blower is preheated in the air preheater by the flue gases

before these are discharged through the chimney. The heated air from air preheater is

supplied to the combustion chamber and it improves the combustion efficiency.



Advantages:-

1. The boiler can generate steam up to a pressure of 150 bars and the generation

rate of steam ranges from 30000 to 45000 kg per hour.

2. Starting of Lamont boiler is quick.

Disadvantages:-

1. Bubbles are formed at the inner face of heating tube. Because of which it

reduces the heat transfer rate.

Result:

me6412 thermal engineering laboratory manual – i

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