Abstract
Abstract A mathematical model is presented for the volumetric combustion of a homogeneous fuel mixture in compression‐ignition and forced‐ignition engines. With careful consideration of all combustion parameters, the profile of the burning rate has a two‐peak structure. A simple nonlinear heat conduction problem was solved to illustrate the importance of including the isobaric process and heat conduction as functions of the temperature. The study shows that, when the pre‐exponential parameter was chosen as a calibrated parameter, the ignition delay time significantly depends on the start of combustion and the pressure in the common rail, while the effect of the engine speed seems less noticeable. The results can be extended to quasi‐sized combustion models.