Numerical simulation on structural optimization design of combustion chamber of high strength diesel engine

Taking the combustion chamber structure of high-strength diesel engine as the research object, the influence of combustion chamber structure on engine performance is deeply explored and the combustion chamber structure is optimized. The combustion chamber structure is parameterized and discretized, and the multi-level calculation of single variable is carried out for all discrete structures. The multi-level calculation results of single variable and the comprehensive processing of multi-level data are taken as the analysis object, and the research objective is to explore the influence laws of all discrete structures on engine performance, so as to complete the exploration and optimization of the combustion chamber structure. According to the CFD simulation calculation of the influence degree of each profile structure on different indexes and the contribution rate of different structures to the same index, it is found that each profile structure is more sensitive to soot emission, and the power of medium line radius in different indexes is the highest. According to the optimization objective determined by the service conditions of the diesel engine, through analysis, the best scheme is 32. The radius of the bowl is increased by 0.1 mm and moved down by 0.4 mm, the necking radius is reduced by 1.2 mm and moved down by 0.2 mm. The optimization function value of the scheme is 78.56%, the power is increased by 1.94%, the NO is increased by 9.6% and the soot is reduced by 84.3%.