Verification of CFD calculation of cavitation with experiment

Abstract

At the moment, there is no unambiguous method for hydrodynamic modeling of the cavitation process of a vane pump and determining the Schnerra-Sauer coefficients using the multiphase flow model «Volume of fluid method (VOF)» for vane pumps with lateral annular supply. The purpose of the article is to test the limits of the applicability of the Schnerr–Sauer model in calculating the partial characteristics of a centrifugal pump at various feeds. The object of the study was a vane cantilever pump with a lateral annular supply and an impeller with five blades. During the work, the value of the cavitation reserve was determined when feeding 120 cubic meters per hour and when feeding 85 cubic meters per hour by an experimental method. The experimental determination of the cavitation reserve was carried out in accordance with the requirements of GOST 6134-87. Cavitation in the pump was achieved by reducing the suction pressure using a vacuum pump. NPSH was also determined by hydrodynamic modeling. In the course of hydrodynamic modeling, the multiphase model «Volume of fluid method (VOF)2 and the cavitation model «Scherr-Sauer cavitation» were used, the selection of Scherr-Sauer coefficients was carried out for supply (120 m3/h), verification according to the underload mode of the pump (85 m3/h). The result of the work is the obtained values of the cavitation reserve and graphs of the partial cavitation characteristics of the pump under study at a supply of 120 cubic meters per hour and at a supply of 85 cubic meters per hour, obtained during the experiment and during CFD modeling, the values of the Schnerr-Sauer coefficients and conclusions on the use of this model.