水压轴向柱塞泵内部空化流动数值模拟

Numerical Simulation of Cavitating Flow in Water Hydraulic Axial Piston Pump

采用Schnerr-Sauer模型对水压轴向柱塞泵内部的空化流动进行了数值模拟,在不同的泵入口压力条件下,对泵出口的流量和压力脉动进行了分析。研究结果表明:当泵入口压力较低时,位于吸水区的柱塞腔内将出现明显的空化,空化区域主要位于柱塞腔的内侧,其中柱塞腔刚进入配流盘吸水槽时的空化最为严重;吸水区柱塞腔严重的空化将会导致泵出口的流量和压力出现较大的脉动;提高泵的入口压力将使空化程度减弱,但过大的泵入口压力会导致柱塞腔在吸水区产生压力冲击;空化程度减弱到一定程度之后,泵进口压力的改变对泵出口的流量和压力脉动不再有显著影响。

In order to study the cavitation characteristics of a water hydraulic axial piston pump, cavitating flow in the pump was simulated based on Schnerr- Sauer model. The fluctuations of flow and pressure at the outlet of the pump were analyzed at different inlet pressure conditions. From the simulation results, it is concluded that obvious cavitations occur in the cylinder chambers which are in suction process. Cavitation regions are mainly located in the sides near to the rotation center, and more serious cavitations occur in the piston chamber which contact with the suction side of the portplate. Dynamic pulsation of flow rate and pressure at the outlet of pump are more severe when serious cavitations occur. Cavitations can be reduced if the pressure at the inlet of pump is increased, but excessive pressure at the inlet can induce pressure pulse in piston chamber which in suction region. When cavitations are decreased to some degree, dynamic pulsation of flow rate and pressure of pump can not be impacted obviously by the pressure at the inlet.