DEVELOPMENT OF VELOCITY PROFILES THROUGH A 4-STAGE LOW-SPEED COMPRESSOR

M. Lange, R. Mailach, R. Müller, K. Vogeler

The evaluation and prediction of end-wall blockage in axial compressors has been investigated by several researchers over the past decades. There are now several approaches known to predict the blockage for the preliminary design of a compressor. Most approaches rely on inhouse data or the few published data sets. This paper presents a set of measurement data from the Dresden 4 stage Low Speed Research Compressor (LSRC), which provides a more complete picture of the end-wall boundary layer development, as it includes data from all axial gaps between consecutive blade rows, as well as a set of data from within a rotor blade row. Velocity profiles are presented together with parameters of the end-wall boundary layer derived from those. In addition to the nominal blockage development a test case with a thick inlet boundary layer pronounces the dependency of blockage on radial clearance sizes.

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