E2

HEAT BALANCE TEST ON SINGLE CYLINDER 4 STROKE DIESEL

ENGINE (KIRLOSKAR)

AIM

To conduct heat balance test on Diesel Engine to prepare a heat balance

sheet.

SPECIFICATIONS:

Engine make: Kirloskar AV1

B.H.P = 5H.P

R.P.M = 1500

Diameter of brake drum =300mm

Orifice Diameter =20 mm

Cd=0.62

PRECAUTIONS

1. Fuel and lubricating oil are checked and if needed they are to be supplied.

2. Cooling water inlet and outlet for engine jacket and brake drum should be

opened.

3. Engine should be started and stopped with no load.

4. De-compression liver should be engaged before cranking.

THEORY:

To balance the energy input and output what is done usually is to add all the known

forms of energy output in heat units and, the difference between this and the given

energy input is termed as unaccounted losses ( lost by radiation etc). Thus law of

conversion of energy is kept unaltered.

1. The work input of engine can be calculated using TFC and calorific value.

2. The heat carried away by cooling water can be calculated from its rate of

flow, specific heat and temperature difference between inlet and outlet.

3. The heat carried away by exhaust gases can be calculated from the exhaust

calorimeter

(1) Time for 10cc fuel consumption = tm (sec)

Total fuel consumption ,

TFC=10tm

×ρ1000

kg /sec

ρ=0.8265gm /cc

Heat Input to the engine ,

i / p=TFC×CV kW

Calorific value (CV ) of diesel = 46057kJ/kg.

(2) Output Power or Brake Power

B .P=2 πNT60

Torque,

T=FR=(W 1−S )×g×R

Where

N = Speed of the engine in rpm,

W 1 = Weight in kg,

S = spring balance reading (kg)

R = (Radius of the brake drum +1/2 the dia of rope) in meters.

R=D2

+ d2

(3)Heat carried awayby cooling water=mwCw (T 2−T 1 )

Where

mw = mass flow rate of water ( Kg/sec)

Cw = specific heat of water ((4.186 KJ/KgK)

T 1 = inlet temperature of water to the engine K

T 2 = outlet temperature of cooling water from engine K

4. Heat carried awayby exhaust gases=meC e (T 4−T R )

Where

me = mass of exhaust gas kg/sec

C e = Specific heat of exhaust gases ( KJ/KgK)

T 4 = Temperature of exhaust gases at engine exit

T R = Room temperature

meC e is obtained from the exhaust gas calorimeter relation as given below

For calorimeter : Heat lost by exhaust gas = heat gained by water

meC e (T 4−T5 )=mwcCw (T 3−T 1)

Where

mwc = mass flow rate of water ( Kg/sec)

CW = Specific heat of water (4.186 KJ/KgK)

T 1 = inlet temperature of water the calorimeter

T 3 = outlet temperature of water from the calorimeter

T 5 = Temperature of exhaust gases at the exit of calorimeter

meC e=mwcCw

T3−T1T 4−T 5

∴ Heat carried awayby exhaust gases ,Qe=meC e (T 4−T R ) kJ/sec

PROCEDURE

The maximum load on the engine is calculated and range of loading is

selected. The necessary precautions are taken. The lubricating oil and fuel in the

tank is checked. The supply of fuel and cooling water is opened. The

decompression lever is engaged and engine is started by cranking. The desired

load is applied and time for 10 c.c of fuel consumption is noted. The temperature

of cooling water at outlet and the temperature of exhaust gas are observed. From

the flow meter the rate of cooling water supply is noted. The atmospheric

temperature and temperature of cooling water inlet are also noted. The

observations are also tabulated as shown. From the observations the heat balance

is done and balance sheet is plotted.

E3

LOAD TEST ON

TWO CYLINDER 4 STROKE DIESEL ENGINE (USHA)

AIM:

To conduct load test (Constant speed characteristics) on Single cylinder 4S Diesel

Engine with rope brake dynamometer and to plot the following Characteristic Curves.

1. Brake power (B.P) Vs T.F.C (total fuel consumption)

2. B.P Vs S.F.C (Specific fuel consumption)

3. B.P Vs M.E (Mechanical efficiency)

4. B.P Vs B.T.E (brake thermal efficiency)

5. B.P Vs I.T.E (indicated thermal efficiency)

6. B.P. vs. volumetric efficiency

SPECIFICATIONS:

Engine make: USHA

B.H.P = 10H.P

R.P.M = 1500

No. of cylinders = 2

Compression ratio = 17.5:1

Bore =87.5mm

Stroke = 110mm

Arm length of hydraulic dynamometer = 320 mm

Orifice Diameter =20 mm

Cd=0.62

PRECAUTIONS

1. Fuel and lubricating oil are checked and if needed they are to be supplied.

2. Cooling water inlet and outlet for engine jacket and brake drum should be

opened.

3. Engine should be started and stopped with no load.

4. De-compression liver should be engaged before cranking.

THEORY:

(1) Output Power or Brake Power

B .P=2 πNT60

Torque,

T=FR=W ×g× R

Where

N = Speed of the engine in rpm,

W❑ = Hydraulic Dynamometer reading

S = spring balance reading (kg)

R = Arm length of hydraulic dynamometer = 320 mm

Time for 10cc fuel consumption = tm (sec)

(2) Total fuel consumption

TFC=10tm

×ρ1000

kg /sec

ρ=826.5gm /cc

(3) Specific fuel consumption

SFC=TFCB . P

kg/kWsec

(4) Indicated Power, I.P = B.P + F.P

Where

F.P is the Frictional Power obtained from the characteristic plot (TFC Vs B.P).

(5) Mechanical efficiency,

ηME=B .P×100

I . P%

(5) Input Power (Heat energy Input),

i / p=TFC×CV kW

Calorific value (CV ) of diesel = 46057kJ/kg.

(6) Brake thermal efficiency,

ηBT=B. P×100

i / p%

(7) Indicated thermal efficiency,

η¿=I . P×100

i / p%

(8) Volumetric efficiency

H air=H w×ρwρair

Hw = Manometer reading (h1-h2)

(a) Actual volume of air taken in,

V actual=Cda√2g H airm3 /sec ( where a= area of orifice)

(b) Theoretical volume

V theoretical=LAN60

k .n( m3

sec) k= ½ for 4 stroke engine, 1 for 2 stroke engine

n = no of cylinders

∴ Volumetric efficiency, (η¿¿vol)¿,

ηvol=V actual

V theoretical

PROCEDURE

Before starting the engine maximum load that can be applied on the engine is

calculated using the formula

B .P=2 πNT60

Torque, T

T=FR=T=FR=W ×g×R

Maximumload= (W ) kg

Start the engine at no load condition. Fuel supply is switched on and the

decompression lever is engaged. The engine is started by manual cranking. Then

the time taken for 10c.c of fuel consumption is noted at no load. And level difference

in the water manometer is noted. Initial load is applied at the end of the hook in the

rope. Note the spring dial reading. Repeat the experiment up to maximum load. Then

the engine is stopped by cutting the fuel supply.

CALCULATIONS:

CHARACTERISTIC CURVES

RESULT:

INFERENCE: