33

CHAPTER 3

WORK UNDERTAKEN

3.1 Fabrication/Development

The project is fabricated in four main steps

Step 1: Adding 2nd Spark Plug in Head of Two Stroke Gasoline Engine:

First of all cylinder head is opened and with help of lathe machine a hole is drilled in the

cylinder head where 2nd spark plug is fitted. After that cylinder head is checked for

leaking and leakage is prevent by applying some industrial glue which can withstand at

high temperature and pressure. Figure 3.1 shows the cylinder head having two spark plug.

Figure 3.1: Cylinder Head having two spark plug

Step 2: Pulley is attached to the flywheel

Figure 3.2: Attachment of Pulley with Flywheel

1st Spark Plug

2nd Spark Plug

Flywheel

Pulley

34

Pulley is attached to flywheel by extending crankshaft. It is useful in measuring brake

power with help of rope brake dynamometer.

Step 3: Mounting Engine on Iron Strip Frame

After attaching the pulley, whole engine is mounted on the frame so that testing can be

done easily.

Figure 3.3: Mounting Engine on Frame

Step 4: Attaching Fuel Bottle for measuring fuel consumption

After mounting the engine on frame, fuel bottle is attached with the input of carburetor.

Main function of this fuel bottle is to supply the fuel to engine.

Figure 3.4: Fuel Bottle arrangement

Iron Frame

Fuel Bottle

35

3.2 Performance Parameters

1. Brake Power

The break power is the power available at the crank shaft. The break power of an I.C.

engine is, usually, measured by means of break mechanism.

Break power (B.P) = 2𝜋𝑁𝑇

60 watts

T = Torque in N-m

= W * L N-m

W = Break load in Newton.

L = Length of arm in meters,

N = Speed of the engine in R.P.M

2. Fuel Consumption

The fuel consumption characteristics of an engine and it is defined as the mass of

fuel consumed per second. Its unit is Kg/sec.

Mass of fuel in kg per second, mf =vρ

t

v = Volume of fuel consumed per second in m3/Sec.

ρ = Density of fuel in Kg/m3

t = Time in Seconds

3. Brake Thermal Efficiency

It is the ratio of the heat equivalent to one KW hour to the heat in the fuel per B.P

hour. It is also known as overall thermal efficiency of the engine.

Brake thermal efficiency, 𝜂𝑡ℎ =Brake power

Energy supplied *100%

Energy Supplied = mf*C

mf = Mass of fuel consumed in Kg/Sec.

C = Calorific value of fuel in KJ/Kg

3.3 Experimental Procedure

The performance test on the engine was carried out as follows:-

At first, it was checked that the fuel tank was filled by fuel and the fuel line were free

from air.

Then the engine was started.

36

By keeping the load constant speed was varied and data were taken when only 1st

Spark Plug is turned ON and when both Spark Plugs are turned ON.

For every 10 cc of fuel consumption the time was taken and noted that for a particular

rpm.

The rpm was taken from the crank shaft by the tachometer.

Similarly five data was taken by the previous procedure.

Figure 3.5: Two Stroke Gasoline Engine Test Rig

3.4 Experimental Data

For 1 Kg Load and only one spark plug is turned on

Table 3.1: Experimental data table for 1 Kg Load and 1st Spark Plug is ON

S.No.

Speed in rpm Time/10cc fuel consumption

(Sec.)

01

2030 110

02

2223 101

03

2310 98

04

2435 91

05 2555 85

37

Table 3.2: Calculation table for load 1 Kg and 1st Spark Plug is ON

For 1 Kg Load and Both Spark Plugs are Turned ON

Table 3.3: Experimental data table for 1 Kg Load and both Spark Plugs are ON

Load

(kg)

S.No. Speed

(rpm)

Time for

10cc fuel

Con.(sec)

Mass of

fuel

consumed

in

Kg per sec

mf*10-5

Brake

power

(KW)

Brake

thermal

efficiency

η(%)

1

01 2030 110 6.73 0.271 8.364

02 2223 101 7.327 0.2969 8.43

03 2310 98 7.55 0.3085 8.49

04 2435 91 8.132 0.3252 8.31

05 2555 85 8.605 0.3412 8.24

S.No.

Speed in rpm Time/10cc fuel

consumption

(Sec.)

01

2038 112

02

2235 104

03

2315 101

04

2431 93

05 2550 88

38

Table 3.4: Calculation table for load 1 Kg and both Spark Plugs are ON

For 1.5 Kg Load and only one Spark Plug is Turned ON

Table 3.5: Experimental data table for 1.5 Kg Load and 1st Spark Plug is ON

Load

(kg)

S.No. Speed

(rpm)

Time for

10cc fuel

Con.(sec)

Mass of fuel

consumed

in

Kg per sec

mf*10-5

Brake

power

(KW)

Brake

thermal

efficiency

η(%)

1

01 2038 112 6.60 0.272 8.56

02 2235 104 7.11 0.298 8.71

03 2315 101 7.32 0.309 8.77

04 2431 93 7.95 0.324 8.47

05 2550 88 8.40 0.340 8.41

S.No.

Speed in rpm Time/10cc fuel consumption

(Sec.)

01

1954 97

02

2103 92

03

2265 90

04

2351 84

05 2447 79

39

Table 3.6: Calculation table for load 1.5 Kg and 1st Spark Plug is ON

For 1.5 Kg Load and Both Spark Plugs are Turned ON

Table 3.7: Experimental data table for 1.5 Kg Load and both Spark Plugs are ON

Load

(kg)

S.No. Speed

(rpm)

Time for

10cc fuel

Con.(sec)

Mass of fuel

consumed in

Kg per sec

mf*10-5

Brake

power

(KW)

Brake

thermal

efficiency

η(%)

1.5

01 1954 97 7.62 0.3914 10.67

02 2103 92 8.04 0.421 10.90

03 2265 90 8.22 0.453 11.46

04 2351 84 8.80 0.470 11.11

05 2447 79 9.36 0.490 10.88

S.No.

Speed in rpm Time/10cc fuel consumption

(Sec.)

01

1960 100

02

2125 94

03

2293 92

04

2365 88

05 2468 83

40

Table 3.8: Calculation table for load 1.5 Kg and both Spark Plugs are ON

For 2 Kg Load and only one Spark Plug is Turned ON

Table 3.9: Experimental data table for 2 Kg Load and 1st Spark Plug is ON

Load

(kg)

S.No. Speed

(rpm)

Time for

10cc fuel

Con.(sec)

Mass of fuel

consumed in

Kg per sec

mf*10-5

Brake

power

(KW)

Brake

thermal

efficiency

η(%)

1.5

01 1960 100 7.40 0.392 11.01

02 2125 94 7.87 0.425 11.22

03 2293 92 8.04 0.459 11.86

04 2365 88 8.40 0.473 11.70

05 2468 83 8.91 0.494 11.52

S.No.

Speed in rpm Time/10cc fuel consumption

(Sec.)

01

1835 77

02

1960 73

03

2042 69

04

2156 67

05 2239 61

41

Table 3.10: Calculation table for load 2 Kg and 1st Spark Plug is ON

For 2 Kg Load and Both Spark Plugs are Turned ON

Table 3.11: Experimental data table for 2 Kg Load and both Spark Plugs are ON

Load

(kg)

S.No. Speed

(rpm)

Time for

10cc fuel

Con.(sec)

Mass of fuel

consumed in

Kg per sec

mf*10-5

Brake

power

(KW)

Brake

thermal

efficiency

η(%)

2

01 1835 77 9.61 0.490 10.60

02 1960 73 10.14 0.523 10.72

03 2042 69 10.72 0.545 10.57

04 2156 67 11.04 0.575 10.83

05 2239 61 12.13 0.598 10.24

S.No.

Speed in rpm Time/10cc fuel consumption

(Sec.)

01

1840 79

02

1963 76

03

2049 72

04

2158 70

05 2242 62

42

Table 3.12: Calculation table for load 2 Kg and both Spark Plugs are ON

3.5 Sample Calculation

Density of Gasoline, ρ=740 kg/m3

Calorific value of Gasoline, C=48100 kj/kg

For 1 Kg Load and Only One Spark Plug is Turned ON

Speed 2310 rpm

Time / 10cc of fuel consumption, t = 98 s

Mass of fuel in kg per second, mf =vρ

t

=740∗10∗10−6

98

= 7.55 ∗ 10−5 kg/s

Energy supplied by fuel = 𝑚𝑓 ∗ 𝑐

= 7.55 ∗ 10−5 ∗ 48100

= 3.63 kw

Brake power, B.P. = T∗2πN

60 =

1∗9.81∗.13∗2∗3.1416∗2310

60

= 0.3085 kw

Brake thermal efficiency, 𝜂𝑡ℎ =Brake power

Energy supplied *100%

Load

(kg)

S.No. Speed

(rpm)

Time for

10cc fuel

Con.(sec)

Mass of fuel

consumed

in

Kg per sec

mf*10-5

Brake

power

(KW)

Brake

thermal

efficiency

η(%)

2

01 1840 79 9.36 0.491 10.91

02 1963 76 9.73 0.524 11.19

03 2049 72 10.27 0.547 11.07

04 2158 70 10.57 0.576 11.32

05 2242 62 11.93 0.599 10.43

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=0.3085

3.63 *100% = 8.49%

For 1 Kg Load and both Spark Plugs are Turned ON

Speed 2315 rpm

Time / 10cc of fuel consumption, t = 101 s

Mass of fuel in kg per second, mf =vρ

t

=740∗10∗10−6

101

= 7.32 ∗ 10−5 kg/s

Energy supplied by fuel = 𝑚𝑓 ∗ 𝑐

= 7.32 ∗ 10−5 ∗ 48100

= 3.52 kw

Brake power, B.P. = T∗2πN

60 =

1∗9.81∗.13∗2∗3.1416∗2315

60

= 0.309 kw

Brake thermal efficiency, 𝜂𝑡ℎ =Brake power

Energy supplied *100%

=0.309

3.52 *100%

= 8.77%

For 1.5 Kg Load and Only One Spark Plug is Turned ON

Speed 2265 rpm

Time / 10cc of fuel consumption, t = 90 s

Mass of fuel in kg per second, mf =vρ

t

=740∗10∗10−6

90

= 8.22 ∗ 10−5 kg/s

Energy supplied by fuel = 𝑚𝑓 ∗ 𝑐

= 8.22 ∗ 10−5 ∗ 48100

= 3.95 kw

Brake power, B.P. = T∗2πN

60 =

1.5∗9.81∗.13∗2∗3.1416∗2265

60

= 0.453 kw

44

Brake thermal efficiency, 𝜂𝑡ℎ =Brake power

Energy supplied *100%

=0.453

3.95 *100% = 11.46%

For 1.5 Kg Load and both Spark Plugs are Turned ON

Speed 2293 rpm

Time / 10cc of fuel consumption, t = 92 s

Mass of fuel in kg per second, mf =vρ

t

=740∗10∗10−6

92

= 8.04 ∗ 10−5 kg/s

Energy supplied by fuel = 𝑚𝑓 ∗ 𝑐

= 8.04 ∗ 10−5 ∗ 48100

= 3.867 kw

Brake power, B.P. =T∗2πN

60 =

1.5∗9.81∗.13∗2∗3.1416∗2293

60

= 0.459 kw

Brake thermal efficiency, 𝜂𝑡ℎ =Brake power

Energy supplied *100%

=0.459

3.867 *100%

= 11.86%

For 2 Kg Load and Only One Spark Plug is Turned ON

Speed 2156 rpm

Time / 10cc of fuel consumption, t=67 s

Mass of fuel in kg per second, mf =vρ

t

=740∗10∗10−6

67

= 11.045 ∗ 10−5 kg/s

Energy supplied by fuel =mf ∗ c

=11.045 ∗ 10−5 ∗ 48100

=5.312 kw

Brake power, B.P. =T∗2πN

60 =

2∗9.81∗.13∗2∗3.1416∗2156

60

45

= 0.5758 kw

Brake thermal efficiency, 𝜂𝑡ℎ =Brake power

Energy supplied *100%

=0.5758

5.312 *100%

= 10.83%

For 2 Kg Load and both Spark Plugs are Turned ON

Speed 2158 rpm

Time / 10cc of fuel consumption, t = 70 s

Mass of fuel in kg per second, mf =vρ

t

=740∗10∗10−6

70

= 10.57 ∗ 10−5 kg

s

Energy supplied by fuel = 𝑚𝑓 ∗ 𝑐

= 10.57 ∗ 10−5 ∗ 48100

= 5.084 kw

Brake power, B.P. = T∗2πN

60 =

2∗9.81∗.13∗2∗3.1416∗2158

60

= 0.576 kw

Brake thermal efficiency, 𝜂𝑡ℎ =Brake power

Energy supplied *100% =

0.576

5.084 ∗ 100%

= 11.32%

3.6 Costing Details

Costing details of the fabrication of project is as follows:

Table 3.13: Costing Details

Sr.

No.

Items Cost ( )

1. Two Stroke Gasoline Engine 5500

2. Spark Plug 300

3. Iron Frame’s Strips 1200

4. Switching Arrangement 700

5. Lathe Work 1000

6. Pulley with Lathe Machine Work 500

7. Extension of Crank Shaft 450

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8. Carburetor Arrangement with Speed Wire 800

9. Miscellaneous Arrangements 200

Total 10,650