Aerodynamic Performance Prediction Of Centrifugal Compressors Based On The Two-zone Model

Centrifugal compressors are widely used in various fields of the national economy due to their advantages of high pressure ratio,wide operating conditions,and compact structure.The research and development of centrifugal compressors need to undergo repeated processes of initial design,trial production,testing and improvement.Therefore,the aerodynamic performance of the initial design scheme directly affects the product development process.With the development of computer and computational fluid dynamics technology,the prediction of aerodynamic performance has become an indispensable tool for the design of centrifugal compressors,and it has important guiding significance for improving and optimizing design schemes.This paper takes the centrifugal compressor as the research object,based on the diffusion model and the two-zone model theory,adopts the FORTRAN language to optimize and improve the existing one-dimensional aerodynamic performance prediction program,and selects the internationally recognized Eckardt impeller and Krain impeller experimental data for verification.The results show that the isentropic efficiency and pressure ratio change trends obtained by the diffusion model and the two-region model are in great agreement with the experimental data,but the prediction accuracy of the two-zone model is higher,which proves the reliability of the program.Research provides analytical tools for the subsequent development of the impeller.In addition,it is considered that the external loss of the impeller is closer to the experimental data than the performance prediction result when the loss is not considered.Then,one-dimensional performance prediction was performed for centrifugal compressors with flow coefficients of 0.02,0.1,and 0.2 with the improved program,respectively,and compared with the corresponding three-dimensional CFD results.For three kinds of flow coefficient centrifugal compressors,the one-dimensional program has a good prediction effect in terms of pressure ratio,isentropic efficiency,and stable operating conditions,indicating that this program has a wide range of application.Finally,in the design process of the 0.2 flow coefficient centrifugal impeller,based on the improved one-dimensional performance prediction program,the rapid performance prediction of the design scheme is performed,which saves a lot of time for the impeller design optimization work.According to the study of this paper,a one-dimensional performance prediction program of centrifugal compressor based on two-zone model was obtained,which provided an efficient analysis tool for the rapid development of centrifugal compressor impeller and diffuser.