Knock prediction using multi-dimensional modeling on gasoline engines

A multi-dimensional model for the simulation of flow and combustion in an engine was extended to knock calculation. A flamelet model proposed by Tahry and based on the probability of finding the flame was implemented for accurate prediction of flame propagation in a homogeneous-charge turbulent pre-mixed combustion. A Shell model proposed by Halstead, modified to satisfy the principle of mass conservation, was used for knock calculation and combined with the flamelet model to estimate the knock onset location. Flame propagation was visualized in an optical access engine, while knock detection was visualized in an actual engine. The results confirmed that the calculations predicted flame propagation well. Simulation of the knock onset location was also shown to be possible.