Numerical analysis of mixing and combustion characteristics of a lateral swirl combustion system in OP2S diesel engines

Opposed-Piston, Two-Stroke (OP2S) diesel engine is a potential powertrain to achieve efficient and clean combustion. However, its non-uniformity of mixing and combustion restricts performance improvement. To solve this problem, this work proposed a lateral swirl combustion system (LSCS) for the OP2S diesel engine. Applying CFD simulation, this work studied the effects of different combustion chamber parameters on the mixing and combustion performance, power, and emissions of the LSCS of the OP2S diesel engine. Furthermore, the combustion parameters were optimized by sensitivity analysis and parameter normalization methods. The results show that the LSCS helps improve the non-uniformity of mixing & combustion of the OP2S diesel engine, accelerate burning, improve the power of the OP2S diesel engine and reduce soot emissions. Besides, under certain fuel supply conditions, it is necessary to make good use of the space of the axial and radial sections of the combustion chamber and make the convex edge height realize the split-flow effect. Therefore the performance of the LSCS can be improved effectively in the OP2S diesel engine.