Application of C_N Group Cyclic Symmetry Method to Three-Dimensional Dynamic Analysis of Centrifugal Compressor and Pump Impeller
Li Songtao(1),Xu Qingyu(1),Zhang Xiaolong(1,2)
(1 Xi'an Jiaotong University, Xi'an, 710049) (2 Xi'an University of Architecture and Technology, Xi'an, 710055)

Abstract: For a centrifugal compressor impeller, three-dimensional finite eleme nt model is established to evaluate the dynamic characters with C_N group cyclic symmetry method, then to obtain stress distribution. Furthermore, the effects of various techniques connecting shaft with impeller of the stress distribution are analyzed. Cyclic symmetry method enables to obviously reduce workload of modeling and calculating to outperform the competing methods in analysis of turbine wheel impeller. It is concluded that in a rotating impeller, its outer part is under a higher stress state and the stress of cover is higher than plate; stress concentration may arise at the blade root. To avoid stress concentration, the blade root ought to be filleted properly. If the impeller is connected with as urplus shaft, the stress near the hole is much higher, so the appropriate surplus is necessary to consider.
Keyword：impeller, cyclic symmetry method, three-dimentional FEM, dynamic analysis.