Experimental and Numerical Determination of Pressure and Velocity Distribution Inside a Rotor-Stator Cavity at Very High Circumferential Reynolds Numbers

Authors

B. Barabas - University of Duisburg-Essen, Germany
S. Clauss - University of Duisburg-Essen, Germany
S. Schuster - University of Duisburg-Essen, Germany
F.-K. Benra - University of Duisburg-Essen, Germany
H. J. Dohmen - University of Duisburg-Essen, Germany
D. Brillert - University of Duisburg-Essen, Germany

Abstract

For many future applications the discharge pressure of industrial radial compressors has to be strongly raised compared to the present situation. An upcoming application for high pressure compressors will be Carbon Capture and Storage technology. The design of high pressure radial compressors strongly depends on the flow structure between the outer sides of the rotor disks and the casing walls. The flow structure inside these so called rotor-stator cavities affects the axial thrust of the machine and the friction at the outer sides of the disks in a significant way. Rotor-stator cavities have been investigated by many researchers experimentally and numerically in the past decades. However, investigations have been conducted for maximum circumferential Reynolds numbers smaller than 2.5x10^7. For described future applications, circumferential Reynolds numbers higher than 10^8 are estimated. In order to close the knowledge gap about flow physics in rotor-stator cavities for highest Reynolds numbers a test rig has been designed and built up at the University of DuisburgEssen. In this contribution, the novel test rig is described in detail and first measurement results are presented. Pressure data inside the cavity gained from experiments are compared to published experimental results. Preliminary CFD results with superposed flow at highest Reynolds numbers are presented and discussed.