Internal Combustion Engine (ICE) Fundamentals

Abstract This is an introductory article, the purpose of which is to provide fundamental information on internal combustion engines (ICEs). In Section 1, the different types of ICEs are presented, and their role in the framework of the energy conversion systems is discussed. The morphology and the basic principles of operation are also described and discussed, along with the different possible classification criteria. The main performance parameters, commonly used for the comparative evaluation of different engines, are also presented and examined. Particular attention is given to the analysis of the ideal cycles to be considered as reference for the actual engines, while the different processes that represent the sources of the losses affecting the engine efficiency are evaluated. The basic principles that underlie the major efforts aimed to the development of new technologies for the reduction of the pollutant and CO 2 emissions are also presented. A section is then dedicated to the presentation and discussion of the legislation framework for the emissions generated by the ICEs, more recently extended from the standard pollutants to CO 2 emissions. The last section is then dedicated to the presentation of the typical engine performance maps and of the fundamental criteria useful for matching with the requirements of a specific application.