Aerodynamic effects of impeller-diffuser axial misalignment in low-flow-coefficient centrifugal compressor  

作　　者：WANG ZhiHeng XI Guang LIU QingFang 

机构地区：[1]School of Energy and Power Engineering, Xi'an Jiaotong University [2]School of Mathmatics and Statistics, Xi'an Jiaotong University

出　　处：《Science China(Technological Sciences)》2015年第1期29-36,共8页中国科学（技术科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.51236006);China Postdoctoral Science Foundation(Grant No.2012M521771)

摘　　要：A numerical investigation on the aerodynamic effects of impeller-diffuser axial misalignment in the low-flow-coefficient centrifugal compressor is conducted through three-dimensional CFD analysis.The results show that the flow,especially near the diffuser inlet,is influenced by the axial misalignment obviously.When the impeller offsets to one side,the pressure at diffuser inlet close to this side will descend,and the vortex in the cavity on the other side will partially enter the diffuser and then result in the back flow.The performances of the stage and its components also change with the impeller-diffuser axial misalignment.There exists an optimum offset making the efficiency maximum at a given operating point.Furthermore,the effect of impeller-diffuser axial misalignment on the axial thrust is pronounced.The axial thrust is nearly increased linearly with the increase of axial misalignment.The aerodynamic effects of impeller-diffuser axial misalignment in the low-flow-coefficient centrifugal compressor behaves more remarkably at the large flow rate.To alleviate the aerodynamic effects of impeller-diffuser misalignment,a rounding in the meridional plane at the diffuser inlet can be applied.

关 键 词：MISALIGNMENT COMPRESSOR low flow coefficient IMPELLER 

分 类 号：TH452[机械工程—机械制造及自动化] U238[交通运输工程—道路与铁道工程]