ABSTRACT
This chapter covers park ignition (petrol) engines. Here the constant volume cycle (Otto) and its basic thermodynamics are considered in detail. A comparison between the basic constant volume cycle and the standard Otto cycle is made and the concept of the air standard efficiency is introduced. The effect of combustion temperature on the emission of NOx is considered, as well as the concepts of brake specific fuel consumption and thermal efficiency. The Morse test for determining indicated power and pumping losses and related calculations is covered. The compression ratio and its effect on thermal efficiency is covered and the fact that above a compression ratio of about 10:1, the increase in efficiency is small.
