Experimental and Numerical Investigation of Radial Flow Compressor Volute Shape effects in Characteristics and Circumferential Pressure Non-uniformity

In this article, the effects of volute cross section shape and centroid profile of a radial flow compressor volute were investigated. The performance characteristics of a turbocharger compressor were obtained experimentally by measuring rotor speed and flow parameters at the inlet and outlet of the compressor. The three-dimensional flow field model of the compressor was obtained numerically solving Navier-Stokes equations with SST turbulence model. The compressor characteristic curves were plotted. For model verification, the results were compared with experimental data, showing good agreement.Modification of a volute was performed by introducing a shape factor for volute cross section geometry. By varying this parameter, new external volutes were generated and modeled while the original volute was intermediate volute. The effect of volute cross section shape on compressor pressure ratio and isentropic efficiency at design rotational speed were investigated.Also pressure non-uniformity around compressor impeller was investigated using pressure taps around the impeller outlet to verify numerical results. This effect was considered and reported for new cases using numerical results.The results show how the shape and centroid profile of volute circumferential cross sections can influence the compressor characteristics and circumferential static pressure non-uniformity.