A Study on Practical Utilization of Diesel Combustion Calculation (First Report)

- A Method of Increasing Calculation Speed -

Abstract

Diesel combustion should be calculated considering chemical reaction at low load operating conditions with EGR, because some heat release from the low temperature oxidation reaction significantly affects ignition delay time. But chemical reaction calculation tends to consume a lot of time. That has hampered to use diesel combustion calculation in actual engine development stages, so many efforts are deployed on speed-up measures for this calculation these days. The authors have already introduced a compact simplified elementary reaction mechanism, but our chemical reaction calculation took too long time because any speed-up measures were not provided. Then some kinds of speed-up calculation algorisms have been tried to use, and a new speed-up method which shares one calculation process with chemical reaction and chemical equilibrium calculations has been invented. The overview of these calculation methods and their speed-up advantages are shown in this paper.