多载荷变形工况下离心压气机叶轮气动优化设计

Aerodynamic Optimal Design of Centrifugal Compressor Impeller Under Multi-load Deformation Condition

为使实际叶片与设计叶片几何偏差最小,综合考虑叶轮内部复杂气动及离心载荷与结构耦合作用,以某小型离心叶轮为研究对象,基于三维流场分析和流固耦合研究叶片几何参数对气动结构性能影响规律及相关性;采用拉丁超立方试验设计、Kriging代理模型和改进遗传算法,以效率、压比和变形为优化目标,进行叶轮多目标优化。结果表明:优化后叶轮效率提高5%,压比提高6.76%,最大变形减小20.4%,内部流动损失减少,载荷分布更加均匀;全流量工况下压比和效率特性提升且变形减小;提出气动与变形预控综合优化设计方法,在设计阶段主动考虑多载荷变形,为离心压气机和其它叶轮机械设计与应用提供重要参考。

In order to minimize the deviation between the actual blade and the design geometry,the coupling of the complex aerodynamic and centrifugal loads with the structure of the impeller was considered.Taking a small centrifugal compressor impeller as the research object,the influences of the geometric parameters on the aerodynamic performance and the correlation between them were studied based on the three-dimensional flow field analysis and fluid structure coupling.Taking the inlet angle,the outlet angle,the tip clearance and the envelope angle as design variables,the multi-objective optimization was conducted to maximize the efficiency,pressure ratio and minimize the deformation by employing the Latin hypercube design,the Kriging model and the improved genetic algorithm.The results show that the efficiency and pressure ratio are increased by 5%and by 6.76%respectively,and the maximum deformation is reduced by 20.4%after optimization.The flow loss reduces and the load distribution is more uniform.The pressure ratio and efficiency characteristics are improved and the deformation is reduced under the whole working range.Considering multi-load deformation in the design stage,a method for aerodynamic optimization and deformation pre-control is put forwards.It provides reference for the design and application of centrifugal compressors and other turbo machinery.