Powerful 1D engine simulation softwares are widely used in the automotive industry to model internal combustion engines. The gas-dynamics exchange process is often well modeled whereas the combustion process is accounted for as a Wiebe function. As the combustion description is a key parameter for engine efficiency evaluation, predictive 0D modeling of heat release seems to be the issue in order to reliably model the cylinder pressure.
A 0D phenomenological SI combustion model is proposed in order to predictively describe the heat release rate, this model being developed with Matlab-Simulink and coupled to GT Power. The model is based on eddy burn up approach and takes into account the geometry of the combustion chamber, the turbulent intensity, the RBG effects. As turbulence is a key feature in SI combustion modeling with eddy burn up approach, at this stage of the study turbulent kinetic energy data resulting from 3D CFD computation was employed.
The model was evaluated on single cylinder engine experimental data, and showed a good agreement for several variations such as compression ratio, inlet valve timing, turbulent intensity and equivalence ratio.