Do you know, some parts of engine like spark plugs, exhaust valves
etc. have very high temperature, around 973 K before the end of compression
stroke. Further, carbon particles will be deposited in various parts of engine
due to incomplete combustion. These carbon particles also have very high
temperature. These overheated things will cause a pre-mature combustion even
before spark application. This pre-mature combustion before the application
of spark is generally called pre ignition.
Then what will happen when spark is applied after pre ignition ?
When spark is applied, then there will be multiple flame fronts
and it will increase the rate of pressure and decrease power output.
Due to pre ignition, more work is needed for compression so that
there is a tendency for mechanical damages such as crank failure. Also it
increases the chance of detonation and knocking. Then we can conclude that this
is a serious problem and major type of abnormal combustion.
No comments:
Post a Comment