Question 43Motor Plants - Assistant Engineer

You are correct, the answer A) begins on a constant volume basis is the correct answer. In a diesel engine, the compression ignition process begins on a constant volume basis. This means that during the compression stroke, the volume of the cylinder remains constant as the piston compresses the air-fuel mixture, causing the pressure and temperature to rise. This compression ignition then initiates the combustion process, which is a combination of the Diesel and Otto cycles. The other answer choices are incorrect because B) compression ignition does not begin on a constant pressure basis, C) the compression ignition process ends on a constant volume basis, and D) the compression ignition process both begins and ends on a constant volume basis, which is not accurate.