某发动机增压器叶轮碎裂失效分析

Failure Analysis of An Engine Supercharger Impeller

本文针对某发动机进行前端轮系交变循环耐久过程中出现的增压器叶轮碎裂故障进行分析,明确叶轮碎裂失效原因为叶轮轮背结构设计不合理而导致应力集中叶轮碎裂,不满足试验要求。优化结构后根据试验边界完成仿真评估及试验验证。仿真计算及试验结果表明:优化结构后叶轮根部应力最大下降34%,叶轮疲劳寿命提升45%;采用改进方案搭载并完成发动机耐久试验,叶轮完好通过试验考核。

In this paper, the failure of supercharger impeller breakage occurred in the process of front-end gear system alternating cycle durability of an engine is analyzed. It is clear that the failure reason of impeller breakage is caused by the unreasonable design of impeller wheel back structure, which leads to the fracture of stress concentrated impeller and does not meet the test requirements. After optimizing the structure, the simulation evaluation and test verification are completed according to the test boundary. The results of simulation and test show that the stress of impeller root decreases by 34% and the fatigue life of impeller increases by 45%. The improved scheme was adopted to carry out the engine endurance test, and the impeller passed the test in good condition.