An Analysis of Spatial Nonuniformity of the Flow at the Entrance Section of the Axial-Radial Impeller of a Centrifugal Compressor Stage Working on Regulation Modes

The article presents an analysis of the experimental data on testing a centrifugal compressor stage on regulation modes by changing the rotational speed of the rotor and the turning angle of the blades in the inlet guide vane unit. The distribution of the angles of attack at the entrance section of the impeller in relation to the blade height is obtained. It is established that a significant difference in the angles of attack from the plug to the periphery influences the polytropic efficiency of the compressor stage. Recommendations are given on the improvement of the mechanism of regulation by the inlet guide vane unit and on the choice of the optimum diameter for the entrance part of the driving impeller blades.

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