Investigating the Effect of the Axial Clearance Magnitude Between the Covering Disc of the Runner and the Centrifugal Compressor Body on the Gas Dynamics in a Low-Discharge Stage Prototype

Abstract

The paper presents the results of numerically investigating viscous gas flow in a simulated low-discharge stage of a super high-pressure type compressor, using the ANSYS CFX software package. We studied the low-discharge centrifugal compressor stage prototype designed and tested at the Compressor, Vacuum and Refrigerating Technology Department of Peter the Great St. Petersburg Polytechnic University. In order to conduct the numerical experiment, we performed a mesh independence study. We compared the properties obtained in the numerical investigation to the experimental data. In our mathematical simulation the magnitude of the axial clearance between the covering disc of the runner and the compressor body varies in the range of 1--5.5 mm; we estimate the effect that varying this number has on the loss complex characteristic 1 + βfriction + βleakage