为提升新设计柴油机的性能，建立了缸内燃烧模拟模型，研究了燃烧室和喷油嘴参数对性能的影响，并根据模拟结果进行样机试制和试验验证。模拟结果表明：喷油嘴凸出高度和喷孔包角对标定工况下燃油消耗率和碳烟排放的影响明显大于对最高热效率工况的影响；喷油嘴流量变化9.09%对最高热效率工况燃油消耗率和碳烟排放的影响很小，但增大流量更有利于控制标定工况下气缸体的高温热负荷；V01~V03三个方案中，与原型机相比，V01方案在最高热效率工况下的高压循环指示燃油消耗率（HPISFC）降幅最大，达4.70%，碳烟排放降低29.72%，而标定工况HPISFC和碳烟排放降幅最小；V02方案在最高热效率工况的HPISFC降幅最小，为4.23%，但在标定工况HPISFC和碳烟排放降幅最大。V01方案试验结果表明，最高热效率工况下有效燃油消耗率降低4.10%，碳烟排放降低30.23%，符合模拟计算对HPISFC和碳烟排放降幅的预期。

In order to improve the performance of a new designed diesel engine, a simulation model of in-cylinder combustion was set up to study the effects of combustion chamber and injector nozzle parameters on combustion performance. Then a prototype of engine was built and tested according to the simulation results. The simulation results show that nozzle protrusion and spray include angle have a significantly greater impact on fuel consumption and soot emissions under the rated operating conditions than under the maximum thermal efficiency conditions. A 9.09% change in injector flow rate has a negligible effect on fuel consumption and soot emissions under the maximum thermal efficiency operating conditions, but increasing the flow rate is more effective in controlling the high-temperature thermal load on the cylinder block under the rated operating conditions. Among the three schemes of V01-V03, V01 scheme achieves the greatest reduction in high-pressure cycle indicated specific fuel consumption (HPISFC) with reaching 4.70% and soot emissions by 29.72% under the maximum thermal efficiency operating conditions, while the reductions in HPISFC and soot emissions under the rated operating conditions were the smallest. V02 scheme shows the smallest reduction by 4.23% in HPISFC under the maximum thermal efficiency operating conditions, but the largest reductions in HPISFC and soot emissions under the rated operating conditions. The test results of V01 scheme indicate that the effective specific fuel consumption reduces by 4.10% and the soot emissions reduce by 30.23% under the maximum thermal efficiency operating conditions, which is consistent with the simulation results regarding the expected reductions in HPISFC and soot emissions.