The analysis on the cavitation performance of a steam turbine lubricating oil pump with consideration of the fluid temperature effect

During the operation of the pump, cavitation can cause performance drop and erosion damage to its flow parts, even can produce noise and vibration. Further, it is well known that temperature variation is of great significance for cavitation in a pump. The present paper treated the numerical analysis of cavitation in a lubricating oil pump under different temperature. In this paper, we used UGS NX to make three-dimensional model of the pump impeller and ICEM to cut the non-structural mesh of the whole flow passage. For cavitating turbulent flow simulation, a newly developed cavitation model based on Rayleigh-Plesset equation was applied. The cavitating turbulent flows in the pump impeller at different oil temperatures from 35°C to 100°C were simulated. The numerical results at different flow discharge were compared with the available experimental data. It was noted that the numerical results by the proposed cavitation model agreed fairly well with the experimental data. The results depicted that the critical cavitation number decreased with the increasing flow discharge. As the oil temperature arose, cavity volume inside the pump impeller shrank, and the depression due to cavitation at higher oil temperatures were verified by the numerical simulation. Thus, the proposed cavitation model was acceptable for the simulation of cavitating turbulent flows in the pump at different oil temperatures.