Numerical simulation of pump cavitations characteristic based on mixture model

In this paper, the cavitation characteristic of a hot water pump was numerically calculated based on mixture model. The critical net positive suction head (NPSHc) was obtained. The vapor volume fractions were obtained in different NPSH by changing the inlet pressure. Changing the temperature of the fluid, NPSHc of the pump were obtained. The results showed that when NPSH decreased, the vapor fraction became large. When pump cavitation is severe, it would fail to run. When the temperature of the fluid increased, NPSHc decreased but did not change so much, because only viscosity was considered in the calculation. Using the method proposed in this article, NPSHc of a pump could be calculated comparable and accurately and the cavitation performance of pump can be predicted. In the real engineering application, we need to determine the installation height of pump according to the NPSHc in operation condition, so as to ensure the reliable operation of the pump.