[Back]

T. Lauer, W. Holly, H. Schuemie, S. Murakami:
"Modelling the Knocking Combustion of a Large Gas Engine Considering Cyclic Variations and Detailed Reaction Kinetics";
Talk: SAE 2014 International Powertrain, Fuels & Lubricants Meeting, Birmingham, UK; 2014-10-20 - 2014-10-23.

The combustion efficiency of large gas engines is limited by
knocking combustion. Due to fact that the quality of the fuel gas has a high impact on the self-ignition of the mixture, it is the aim of this work to model the knocking combustion for fuel gases with different composition using detailed chemistry. A cycle-resolved knock simulation of the fast burning cycles was carried out in order to assume realistic temperatures and pressures in the unburned mixture Therefore, an empirical model that predicts the cyclic variations on the basis of turbulent and chemical time scales was derived from measured burn rates and implemented in a 1D simulation model. Based on the simulation of the fast burning engine cycles the selfignition process of the unburned zone was calculated with a
stochastic reactor model and correlated to measurements from the engines test bench. A good agreement of the knock onset
could be achieved with this approach.