Influence on the gas-dynamic characteristics axial gap between the impeller and the housing of centrifugal compressor.

The paper presents the results of a numerical study of the viscous gas flow in a model stage centrifugal compressor with a low-flow coefficient using the Ansys CFX software package. The object of study is a model stage centrifugal compressor with low-flow coefficient, designed and tested at the Department of Compressor, Vacuum and Refrigeration Engineering of St. Petersburg Polytechnic University (hereinafter referred to as the Department of CVRE). To conduct a numerical experiment, a study on grid independence is carried out. The characteristics obtained from the results of a numerical study are compared with experimental characteristics. In the mathematical model of the stage, the magnitude of the axial clearance between the covering disk of the impeller and the compressor housing varies from 1 mm to 5.5 mm and the effect of changes in this value on the characteristic of the loss complex 1 + βfr + βpr is estimated. [ABSTRACT FROM AUTHOR]