Investigation of the cavitation performance in an engine cooling water pump at different temperature

Cavitation damage in engine cooling water pump is the main factor that shortens the lifespan of the cooling system and gives rise to undesirable phenomena such as vibration and noise. In order to reveal the influence of key factors such as temperature and speed on the cavitation performance of engine cooling water pump, the cavitation performance of the engine cooling water pump under different rotating speeds and temperatures is obtained through the experimental study, and the cavitation flow pattern in the engine cooling water pump under different temperatures is captured using high-speed photography. The result shows that, as the temperature of the working medium changes from 25 °C to 70 °C, the head of the pump increases by 5.9% under the part-loading condition, the efficiency has an increase by 7.1% near the design condition and the shaft power keeps decrease by about 5.6%. Cavitation performance under different rotating speeds is found not to agree with the similar law. With the increase of temperature, the inlet pressure of cavitation initial increases and the cavitation performance deteriorates, the cavitation distribution region inside the impeller gradually expands and presents asymmetric distribution, indicating that thermodynamic effect has a positive effect on the occurrence of cavitation in the engine cooling water pump.