轴向柱塞泵内部空化流的可视化分析

Visualized Analysis of Cavitation Inside Axial Piston Pump

通过设计泵的模型对轴向柱塞泵的配流盘的切口(V型槽)附近喷射流动进行可视化分析。使用高速摄像机从轴向和垂直于轴的方向能够清晰地观测到空化现象。另一方面,应用三维DES(Detached Eddy Simulation,分离涡模拟)湍流空化模型进行CFD仿真分析来估计空化现象的发生和区域。通过比较在3 MPa和5 MPa压力(300 r/min和600 r/min泵转速)条件下空化的仿真和实验结果,表明CFD仿真与可视化实验有很好的一致性,对于估计空化的范围是非常有用的。进一步得到了24 MPa(2400 r/min泵转速)情况下的空化云图并讨论了气蚀的产生。最后通过使用3个V型槽的配流盘成功地抑制了空化效应。

In the present research,our pump model is designed to visualize the jet flow near a notch（ V-shaped groove） of a valve plate in an axial piston pump. The cavitation cloud can be observed clearly by a high-speed video camera from the axial direction and the perpendicular direction to the axis. On the other hand,a three dimensional DES（ Detached Eddy Simulation） turbulent model with cavitation model is used in the CFD simulation to estimate the occurrence and the region of the cavitation cloud. The CFD results are in good agreement with the visualization results after the simulated regions of the cavitation cloud are compared with that of the experimental results at3 and 5 MPa（ 300 and 600 r / min）. It is found that our CFD method is very useful for estimating the region of the cavitation cloud. Furthermore the cavitation cloud at 24 MPa（ 2400 r / min） is obtained by the CFD method and the erosion in that case is discussed. Finally we succeed to reduce the cavitation region by using the valve plate with three notches.