NUMERICAL STUDIES OF LOW-SOLIDITY TANDEM CASCADE DIFFUSERS IN CENTRIFUGAL COMPRESSORS

摘要

Since 1980's the LSC(Low Solidity Cascade) diffusers have been widely used in process industry centrifugal compressor production, but there have been limited published materials about the design approaches and firm design criteria for low solidity diffusers. An inviscid-viscous iterative code and a three-dimensional N-S solver have been developed respectively, for a better understanding of the flow phenomena in low solidity diffusers and to improve the corresponding design approaches and analysis methods. A detailed numerical study of the flow near chock and near stall for Senoo LSC tandem diffuser is presented by means of both methods, and the published measurements'1' have been used to assess the numerical methods.