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Experimentally obtained energy release results, a semi-empirical ignition model, and an empirical energy release equation developed during this research were used to evaluate the combustion of compression-ignited homogeneous mixtures of fuel, air, and exhaust products in a CFR engine. A systematic study was carried out to evaluate the response of compression-ignited homogeneous charge (CIHC) combustion to changes in operating parameters with emphasis being placed on the phenomena involved rather than the detailed chemical kinetics. This systematic study revealed that the response of the combustion process to changes in operating parameters can be explained in terms of known chemical kinetics, and that through the proper use of temperature and species concentrations the oxidation kinetics of hydrocarbon fuels can be sufficiently controlled to allow an engine to be operated in a compression-ignited homogeneous charge combustion mode.

The heat release type models have been classified as zero-dimensional because they have no spatial resolution and therefore don't contain any information on the fluid mechanics in them. They have been a significant contribution because they incorporate the rate processes occurring in the engine and are an aid in the analysis of the data. Because they are thermodynamic models it is necessary to define the control volumes on which the thermodynamic analysis is to be performed. The different control volume descriptions, called one, two and three zone models, and the analysis of the combustion event using these models is discussed. Finally a description of second law zero-dimensional models is given. These models have similar limitations as the First Law models; no spatial resolution and a control volume definition is required. These models are useful because they enable one to analyze the magnitude of the losses that occur in the different processes which comprise the engine cycle.