为解决爆破试验条件下离心压缩机齿轮箱出现裂纹的问题,运用UG、HyperMesh与Optist-ruct软件分别对箱体进行三维重建、网格划分与有限元分析,以确定其最大应力与应变及其区域。结果表明,最大应力为1 096 MPa,不满足要求。为此,以单元密度为设计变量,体积最小为目标函数,最大应变处单元位移不超过0.2 mm为约束条件,利用Optistruct软件对其进行拓扑优化,并对优化后的结构重新进行强度校核,最大应力降低为228 MPa,低于材料许用强度,符合要求。爆破试验也表明,优化后的样机不再出现上述问题。
In order to solve the problem of cracks for the gear-box of the centrifugal compressor on the condition of blasting experiment, a three-dimensional model of the gear-box was built by UG and HyperMesh softwares. Finite element analysis was performed and the regions with the maximum stress and maximum strain were obtained. The maximum stress of 1 096 MPa was obtained and it couldn't meet the requirements. According to the results of finite element analysis, topology optimization was conducted for the gear-box by OptiStruct software. In the optimization, minimum volume was defined as objective function, the element displacement at the maximum strain location not more than 0.2 mm was used as the constraint function and the element density was adopted as the design variable. The strength of the optimized structure was checked and the maximum stress was reduced to 228 MPa. It was less than the allowable stress of material of the box and satisfied the design requirements. The blasting experiment resuhs verified the success of topology optimization for the gear-box.