NUMERICAL ANALYSIS OF MIXTURE FORMATION AND COMBUSTION EVOLUTION IN DIRECT INJECTION JET IGNITION GAS ENGINES

摘要

A more sustainable transportation calls for the use of alternative and renewable fuels, a further increase of the fuel energy conversion efficiency of internal combustion engines, as well as the reduction of the thermal engine energy supply by recovering the braking energy. The paper presents a combustion system concept being developed to improve the fuel conversion efficiency of internal combustion engines for transport applications fuelled with gaseous fuels. The combustion system comprises a direct fuel injector and a jet ignition device. The combustion evolution is optimized to increase the amount of fuel energy transformed in piston work within the cylinder by modulating premixed and diffusion combustion processes. Results of CFD simulations with detailed chemistry are presented in the paper.