Development of Time-Scale Interaction Combustion Model for Gasoline and Diesel Engines

The combustion processes of both gasoline and diesel engines are becoming similar, as a result of the application of direct fuel injection to the former and the reduction of the compression ratio of the latter. A novel time-scale interaction (TI) combustion model has been developed for simulating combustion phenomena with high accuracy, ranging from premixed charge combustion to diffusion combustion. This model is based on reasonable combustion modes, taking into account the characteristic time scales of the chemical reactions and turbulence eddy break-up. Comparisons of measured and calculated heat release rate patterns and cylinder pressure histories showed good agreement for various operating conditions. The diesel combustion mechanism was analyzed under several fuel injection timings and engine loads using the TI combustion model.