Threshold sensitivity study on spray–spray impingement under flexible injection strategy for fuel/air mixture evaluation

To further improve the combustion and emissions performance of opposed-piston two-stroke (OP2S) engines, the implementation of a flexible injection strategy is crucial. The employed double injectors with different nozzle orifice diameters at different timings could make it easier to adjust the concentration stratification of the fuel–air mixture and better control the combustion characteristics. Despite the benefits, spray–spray impingement (SSI) is an unavoidable consequence of employing a dual direct injection system in OP2S engines. Therefore, this study aims to explore the influence of the flexible injection strategy on the SSI phenomenon. The results indicate that the impingement spray area and air…