Combustion and Emissions of a Lateral-Swirl Combustion System in Diesel Engines

Lateral-swirl combustion system(LSCS) can improve the fuel/air mixture formation and then decrease the fuel consumption and emissions in diesel engines.The mechanism of fuel/air mixing in a diesel engine with LSCS was analyzed through CFD simulation.The influences of fuel jet orientation angle and fuel spray angle on the LSCS combustion and performances were conducted by engine testing and CFD simulation, respectively.The result shows that the LSCS gets the best performance when the fuel jet orientation aims at the tip of convex edge.Experiments under different operating conditions were conducted on a single-cylinder diesel engine.The result shows that with the optimized LSCS, the brake specific fuel consumption decreases by about 2% and the smoke emissions decreases by about 60% compared with the DSCS(double-swirl combustion system) under the same operating conditions.Moreover, the LSCS shows good combustion and performances in the lower excess air coefficient of 1.3-1.6.