The following combustion chamber design changes increase the mass burning rate in a spark-ignition engine at fixed compression ratio, bore, speed, and inlet mixture conditions. Explain how each change...

The following combustion chamber design changes increase the mass burning rate in a spark-ignition engine at fixed compression ratio, bore, speed, and inlet mixture conditions. Explain how each change affects the burning rate.

(a) Reducing the amount of EGR.

(b) Using two spark plugs per cylinder instead of one.

(c) Generating swirl within the cylinder using a mask on the cylinder head (see Fig. 8-14). (4 Using a combustion chamber with higher clearance height near the spark plug and a more central plug location.