基于非线性重构的跨声速压气机叶片静气动弹性分析

Static Aeroelastic Analysis of Transonic Compressor Blade Based on Nonlinear Reconstruction Method

关键词:  压气机  叶型重构  流固耦合  气动弹性  非线性

Key words:  Compressor  Blade reconstruction  Fluid-structure interaction  Aeroelasticity  Nonlinearity

摘要:

工作状态的压气机转子叶片在气动力及离心力作用下会发生变形，准确的叶片构型预测对于压气机性能分析和检验具有重要意义。为研究叶片气弹变形对压气机气动及结构参数的影响，采用非线性叶型重构方法获得了Stage 37转子叶片在不同工况下的热态构型。在计算叶片变形时，计入了叶片受力载荷随构型变化的非线性特征以及叶片的变刚度特性，叶片受力载荷与刚度矩阵随叶片构型同步更新。考察了不同工况下热态叶片的变形规律，研究表明:叶型重构方法可有效提高压气机气动性能的预估精度。设计转速下，热态叶片的堵塞流量及近失速点压比较冷态叶片分别增加1.2%和0.24%，叶片变形对气动特性的影响随转速增加而增强。离心力对叶片变形起主要作用，然而气动力的压力反扭作用不可忽略，设计转速下近失速点反扭角较堵塞点增加了14.7%。计算跨声速转子热态叶片构型时，需考虑离心力和气动力的综合作用。

Abstract:

The aerodynamic and centrifugal loads acting on compressor rotor blade in operation deform the blade configuration relative to its stationary shape. Accurate prediction of the running blade configuration has a significant role in examining and analyzing compressor performance. In order to study the effects of blade aeroelastic deformations on aerodynamic and structure parameters of the compressor，a nonlinear reconstruction method is employed to determine the hot blade shapes of Stage 37 rotor blade under different operating conditions. When calculating blade deformations，the nonlinear effects of stiffness and loads arising from the blade deflections are taken into account. The blade stiffness and load conditions are updated synchronously with the variation of blade shape. The deformation law of hot blade are analyzed under different working conditions. The results show that the accuracy of aerodynamic performance predictions can be improved by using blade reconstruction method. At design speed，the choke mass flow rate of the hot blade increases by 1.2% compared to the cold blade. The influence of blade deformations on compressor performance increases with rotating speed. At near stall point，the total pressure ratio of the hot blade increases by 0.24% compared to the cold blade. The centrifugal load has a major impact on blade deformation. However，blade untwist caused by aerodynamic load can not be ignored. At design speed，the untwist angle near stall point increases by 14.7% compared to that at choke condition. Both aerodynamic and centrifugal loads should be taken into account when calculating transonic rotor running blade configuration.