Numerical simulation on the combustion and emission characteristics of a diesel engine with double ω combustion chamber

To improve the spray spatial distribution and the mixture formation quality in diesel engines, a combustion system with a double-ω combustion chamber and a double-row orifice nozzle is proposed. A numerical simulation on its in-cylinder spray, mixture formation and combustion process with different positions of spray drop points is conducted by using AVL FIRE software, and the effects of different positions of spray points on the air velocity field and mixture concentration and temperature fields in combustion chamber as well as combustion and emission characteristics are analyzed. The results show that the position of spray drop point has a great influence on combustion and emission performance. Using the injector with double-row orifice nozzle can effectively improve the quality of combustible mixture formation with the highest level of soot emission reduces by 57.8% compared with traditional injector with single row orifice nozzle.