波子结构法在失谐带分流叶片离心叶轮动态特性分析中的应用

为解决高保真失谐叶轮模型计算量大的问题,在Craig-Bampton部件模态综合法的基础上,结合波子结构法对界面自由度进一步减缩,发展了适用于带分流叶片离心叶轮的模型减缩方法,并给出其复数形式下的数学表达.采用该方法建立了工程实际叶轮高保真有限元模型的减缩模型,自由度数减缩率达99.8％.分别采用减缩模型和完整模型,通...

Application of Wave-Based Substructuring Approach in Dynamic Characteristics Analysis of Mistuned Impellers with Splitter Blades

A reduced order modeling method is developed for impellers with splitter blades, which combines the wave-based substructuring approach and the Craig-Bampton component mode synthesis method, and the formulas are described in complex form. The high fidelity finite element model (FEM) and the corresponding reduced order model (ROM) of the impeller are established. The reduction rate of the total degrees of freedom is about 99.8%. Both ROM and FEM are used to conduct the modal analysis. Relative errors of modal frequency and modal assurance criterion (MAC) value are calculated and the results demonstrate the accuracy of the ROM and verify the robustness of the reduction basis composed of waves. The normalized maximum displacement amplitudes are calculated for different mistuning levels and different engine orders with ROM and FEM respectively. The relative errors of the response amplitudes are calculated and the accuracy of the ROM is further verified. Both modal and forced response results suggest the proposed ROM has high calculation precision.