为满足国六排放标准下中重型柴油机全工况性能提升需求，针对其匹配的离心压气机开展气动性能与结构可靠性协同优化。通过对叶轮平均子午型线与叶片载荷分布进行优化设计，结合NUMECA软件三维流场仿真，获得了压比与效率同步提升的叶轮方案，峰值效率提高约3个百分点。流场分析表明：优化后叶轮内部静压沿流向分布更均匀，叶顶间隙流动改善，流动损失显著降低；同时叶轮出口掺混损失减小，进而扩压器扩散损失降低。在此基础上同步开展叶轮结构可靠性设计，优化后叶轮关键位置应力分别降低27%和67.5%，出口倒角处应力降低10%以上。采用五轴铣削工艺完成样件试制，压气机台架试验验证了优化方案的可行性。发动机台架对比试验表明：搭载优化压气机后，发动机外特性油耗降低0.6~1.9个百分点，最佳油耗点改善1.1个百分点，各项性能指标均满足技术要求。

To meet the performance-improvement requirements of a China Ⅵ compliant medium and heavy duty diesel engine under full-operating-conditions, a co-optimization of aerodynamic performance and structural reliability was conducted for its matched centrifugal compressor. The meridional contour and blade loading distribution of the impeller were optimized. Three-dimensional flow-field simulation using NUMECA software showed that the optimized compressor achieved synchronous enhancement in pressure ratio and efficiency with a peak-efficiency increase of approximately 3 percentage points. The flow-field analysis indicated that the optimized compressor impeller could achieve a more uniform static-pressure distribution along the flow direction inside the optimized impeller, which effectively suppressed flow losses, especially in the tip-clearance region. Moreover, the mixing loss at the impeller outlet reduced, thereby the diffusion loss in the diffuser reduced. Based on the aerodynamic optimization, the structural reliability design was further performed. The results demonstrated that the stress at critical locations of the optimized impeller decreased by 27% and 67.5% respectively, while the stress at the outlet fillet dropped by more than 10%. A prototype was manufactured via five-axis milling, and the compressor rig tests verified the feasibility of the optimized design. Engine bench comparison tests revealed that the fuel consumption at full-load conditions reduced by 0.6-1.9 percentage points, and the fuel consumption at the best-efficiency-point improved by 1.1 percentage points after using the new compressor. All performance indicators met the technical requirements.