Applying a Tabulated Chemistry Approach for the Calculation of Combustion and Emissions in Diesel Engines

It is generally acknowledged, that more details of the chemical reactions occurring in the flame front should be accounted for in the CFD simulations, but with increasing the number of species and reactions involved the associated CPU cost grows quickly beyond practical engineering time limits. Aim of this work is to increase computation efficiency by using a tabulation technique, without losing any accuracy. In order to achieve these goals, dedicated software solution for the generation of CFD look-up tables for advanced combustion models, is applied. Simulations were run for real life Diesel engine, for 5 different EGR levels. FGM results are showing very good match with measurements and direct calculation of the chemical reactions. The runtime for CFD simulations, including chemistry pre-processing, does only mildly increase with the number of species used in the reaction mechanism; simulations with 1000+ species have been realized within 20 hrs on 8 CPU cores