State the effect of compression ratio and turbulence on ignition lag.

State the effect of compression ratio and turbulence on ignition lag.
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1 Answer

Answer :

Effect of engine variables on ignition lag 

1) Compression ratio: A higher compression ratio increases the pressure and temperature of the working mixture and decreases the concentration of the residual gases. These favorable conditions reduce the ignition lag of combustion. 

2) Turbulence: Ignition lag is not much affected by turbulence intensity. It measured in degree of crank-rotation the ignition lag increases almost linearly with engine speed. For this reason. It becomes necessary to advance the spark timing at higher speed. 
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