Fluid analysis of the cavitation of the microsegment gear pump operating at high-pressure condition

Abstract

To investigate the cavitation of the microsegment gear pump and its effect on the performance of the gear pump, the gear equations of the microsegment gear for the pump were given, the cavitation mechanism was described, and the dynamic cavitation model was derived. The fluid analysis of the microsegment gear pump was carried out using the computational fluid dynamics software (Fluent), and the evolution of cavitation and its effect on the outlet flow characteristics were investigated. The results show that: the vortex occurred at the back edge of the microsegment gear pump suction chamber teeth and the top of the teeth, thus producing cavitation; the cavitation presented periodic formation-development-disappearance of the process; cavitation led to increased outlet flow fluctuations and pressure pulsations, and also led to a decrease in the average value of outlet flow and average value of outlet pressure. The periodic cavitation led to the periodic fluctuation in outlet flow and pressure. At the same time, cavitation also caused a decrease in the total head of the microsegment gear pump. Cavitation in the microsegment gear pump increased with increasing the speed and decreasing the suction pressure.