With focus on the difficulty of mixture formation of an opposed piston opposed cylinder diesel engine

CONVEGE CFD software was employed to establish the numerical simulation model of an opposed piston opposed cylinder diesel engine. Three arrangements of the converging group-hole nozzle were designed

and without modifying the injection pressure

the fuel spray

mixture formation and combustion process of an opposed piston opposed cylinder diesel engine model were analyzed. The results indicated that the group-hole nozzle had negligible influences on spray penetration distance compared with conventional nozzle. The group-hole nozzle was helpful in improving the in-cylinder turbulence kinetic energy and accelerating the air-fuel mixing rate. Meanwhile

the mixture was evenly distributed and widely spread

helping to improve the quality of mixture and increase the in-cylinder pressure and combustion efficiency as well as improve the engine performance. Among three designs

the indicated power of the engine with the third pattern of converging group-hole increased by 7.6%.