Question

There is no spark plug in diesel engine. Why?

Answer 1

A diesel engine works on compression ignition where the air is heated to high temperature and brought to a higher pressure by compression of the piston leading auto ignition of fuel and air mixture. The calorific value of the Diesel engine is more when compared with the petrol engine. For less calorific value we do not get more horse power. But diesel have more heat developed during combustion thus developing more power than petrol engines. Thus there is no need of Sparking the air- fuel mixture in the diesel engine.