Combustion based Report and Analysis

On

ULSD > Ultra Low Sulphur Diesel B100 > 100% Biodiesel B100adv. > 100% Biodiesel with advanced

injection timing of 3°.

Combustion Analysis Cylinder pressure vs Crank angle data from the actual test of a Metro bus will be used in this experiment to obtain quantitative information on the progress of combustion. Heat release rate is the key parameter of combustion analysis and can be obtained by using the following equations.

Performance Test To analyse the performance of an engine, the required parameters are, efficiency (η), torque (T), output power (P) and input energy (Q). The efficiency of the engine can be obtained from the following relation

We have to download the data and calculate the above equations and put it in a graph. The Fuels that were given are: ULSD > Ultra Low Sulphur Diesel B100 > 100% Biodiesel B100adv. > 100% Biodiesel with advanced injection timing of 3°. After finding the required data, the graphs that were plotted for the above fuels were: 1. P vs. θ

2. dQ/dθ vs. θ

3. Q vs. θ

The Graphs are as follows:

P vs. θ

Series 1 - ULSD

Series 2 - B100

Series 3 - B100 (3° Adv)

0

1000000

2000000

3000000

4000000

5000000

6000000

7000000

0 100 200 300 400 500 600 700 800

Pre

ssu

re

Theta θ

Series2

Series3

Series1

dQ/dθ vs. θ Series 1 - ULSD

Series 2 - B100 Series 3 - B100 (3° Adv)

-200

-100

0

100

200

300

400

0 100 200 300 400 500 600 700 800

dQ

/dθ

Theta θ

Series2

Series3

Series1

Q vs. θ

Series 1 - ULSD Series 2 - B100 Series 3 - B100 (3° Adv)

-2000

0

2000

4000

6000

8000

10000

12000

0 100 200 300 400 500 600 700 800

Inp

ut

Ene

rgy

(Q)

Theta θ

Series2

Series3

Series1

The Performance Report for the fuels is as follows:

Calorific value (CV) of diesel 44514 kJ/kg Calorific value (CV) of B100 38730 kJ/kg

ULSD No.Of

Run Speed Power Torque Fuel Flow bsfc Efficiency

(ŋ)

(rev/min) (kW) (N-m) (g/h) (g/kWh) (%)

1 2421 88.99275 1820.48128 34929.85972 392.502288 20.60457621

2 2206 101.0067 2166.186622 32132.13213 318.1186992 25.42240782

3 2002 100.2484 2451.012552 29609.60961 295.362379 27.38108805

4 1792 95.25 2670.527559 27507.50751 288.7927297 28.00397127

5 1598 89.52787 2817.939693 25108.21643 280.4514127 28.83687848

6 1410 80.14068 2908.809374 22102.1021 275.7912914 29.32414315

7 1191 64.07429 2717.900968 18276.55311 285.2400262 28.35276457

8 1015 46.54604 2352.143685 14252.25225 306.1968939 26.4122317

B100 No.Of

Run Speed Power Torque Fuel Flow bsfc Efficiency

(ŋ)

(rev/min) (kW) (N-m) (g/h) (g/kWh) (%)

1 2404 82.59004 1691.213701 36733.46693 444.7687375 18.18325486

2 2199 91.70027 2002.869505 34714.71471 378.5672214 21.36303106

3 1994 91.04711 2220.965653 32404.80962 355.9125753 22.72283664

4 1803 87.62211 2408.961886 29038.07615 331.401261 24.40347778

5 1602 81.61368 2523.252747 26332.66533 322.6501596 25.0653628

6 1402 72.40445 2582.66842 23326.65331 322.1715321 25.10260064

7 1201 57.48059 2403.369151 18415.24574 320.3732806 25.24350125

8 1002 39.72849 1953.724002 12698.09428 319.6218341 25.30284995

B100 (adv)

No.Of Run Speed Power Torque Fuel Flow bsfc

Efficiency (ŋ)

(rev/min) (kW) (N-m) (g/h) (g/kWh) (%)

1 2399 88.77543 1828.387716 38472.36181 433.3672166 18.66164075

2 2199 100.0907 2244.72973 36084.33735 360.5162641 22.43267256

3 2004 98.02512 2427.698551 34096.38554 347.8331398 23.25064056

4 1798 95.32623 2610.923524 30571.71515 320.7062083 25.21729576

5 1600 90.18375 2789.373308 27562.68806 305.6280907 26.4613874

6 1398 80.10738 2832.908917 24482.41206 305.6199227 26.46209461

7 1202 54.23897 2252.000383 18512.56281 341.3147649 23.69467758

8 998 40.49714 1995.257143 13326.63317 329.075886 24.575922

Based on the Performance Report we are to plot three graphs for the fuels.

1. Torque vs. speed

2. Power vs. speed

3. Bsfc vs. speed

4. Efficiency vs. speed

The graphs for the fuels have been combined into one for comparison. The graphs can be seen below:

Torque vs. speed

Series 1 - ULSD Series 2 - B100 Series 3 - B100 (3° Adv)

0

500

1000

1500

2000

2500

3000

3500

0 500 1000 1500 2000 2500 3000

Torq

ue

Speed

Series2

Series3

Series1

Power vs. speed

Series 1 - ULSD Series 2 - B100 Series 3 - B100 (3° Adv)

0

20

40

60

80

100

120

0 500 1000 1500 2000 2500 3000

Po

we

r

Speed

Series2

Series3

Series1

Bsfc vs. speed

Series 1 - ULSD Series 2 - B100 Series 3 - B100 (3° Adv)

0

50

100

150

200

250

300

350

400

450

500

0 500 1000 1500 2000 2500 3000

bfs

c

Speed

Series2

Series3

Series1

Efficiency vs. speed

Series 1 - ULSD

Series 2 - B100 Series 3 - B100 (3° Adv)

0

5

10

15

20

25

30

35

0 500 1000 1500 2000 2500 3000

Effi

cie

ncy

(η)

Speed

Series2

Series3

Series1

Angles of occurrence of the peak pressures

ULSD

Pressure (N/m2) θ in Degrees

5117203 371.7351

5117188 371.9226

B100

Pressure (N/m2) θ in Degrees

5201575 372.6034

5201688 372.7641

B100 (3 Adv)

Pressure (N/m2) θ in Degrees

6246713 370.3667

6247067 370.5274

Ignition delays and combustion durations (in angle)

ULSD 360.157

B100 361.8623

B100 (3° Adv) 358.956

Minimum bsfc

ULSD -> 275.8 g/kWh

B100 -> 319.6 g/kWh

B100 (3° Adv) -> 305.6 g/kWh

Maximum Efficiency (η)

ULSD -> 29.30%

B100 -> 25.30%

B100 (3° Adv) -> 26.50%

Conclusion:

Based on the data and performance analysis, it can be concluded that using B100 could impact power. The vehicle would lose power. By advancing the ingnition timing of B100 (adv) we could get increased Torque at higher rpm. Also by advancing the ingnition timing, the bsfc was found to be lower than B100. This also means that lower bsfc rates can be achieved by advancing the ignition timings.