Assignment 2

1.Run the case at 1800 rpm and list down important parameters

• airflow rate :24.6 kg/h
• BMEP (IMEP-Frictn) : 9.5 bar
• BSFC : 239.2 g/kWh
• In-cylinder pressure : 48.89 bar

2. Increase the power output at 3600 rpm by 10%

The present system has a power of 16.3 kW at 3600rpm.

To increase the power output of the system the parameters like bore, stroke, and compression ratios are taken into consideration.

a. Effect of Bore on engine power

With the increase in Bore the power increases. We can see a maximum value of 18.4 kW at 90mm bore.

b. Effect of Stroke on engine power

With the increase in Stroke the power increases. We can see a maximum value of 17.5 kW at 90mm Stroke.

C. Effect of Compression ratio on engine power

With the increase in the Compression ratio of the cylinder the power increases. We can see a maximum value of 17.2 kW at CR ratio 11.

These were the cylinder parameters considered. We can also consider other parameters like Fuel flow rate, anchor angle, combustion duration etc but these values have more influence on the combustion-related and BSFC values.

Finally a combinations of:

Bore: 90mm Stroke:86mm CR :10.5 was used to increase the power of the engine from 16.3 kW to 18.4 kW which is 12% increase in power.

Further, in order to control the cylinder pressure and Nox emissions from the engine, the A/F ratio and Anchor angles were adjusted in iteration to get the desired value.

Results:

The engine power output was increased to 12% from 16.3kW to 18.4kW. Also the NOx value from 4286.28 to 3.127 and cylinder pressure value which is an indication of knocking is also reduced from 2.147 to 1.993