Study on Restraining Cavitation of Axial Piston Pump Based on Structure of Cylinder Block and Valve Plate Triangular Throttling Groove

Raising the rotational speed is an effective way to improve the power density of axial piston pump, but high rotational speed tends to cause plunger cavity and valve plate throttling groove cavitation. The cavitation of axial piston pump must reduce its volumetric efficiency and cause vibration and noise. In order to reduce the cavitation of axial piston pump and improve the performance of axial piston pump, the optimization of anticavitation structure parameters of cylinder block and valve plate throttling groove is studied in this paper. Firstly, according to the condition of no cavitation in the piston cavity fluid, the mathematical model of the ratio of plunger cavity diameter to axial piston pump cylinder block kidney hole hydraulic diameter is established. It is found that when the ratio is small, the cavitation degree of the piston cavity is weakened. Secondly, this paper analyzes and studies the influence of the valve plate triangular throttling groove structure parameters on the cavitation flow of the triangular throttling groove. It is found that reducing the structural parameters γ or θ can reduce the cavitation intensity of the triangular throttling groove fluid. Finally, combined with the analysis result of the ratio of piston cavity between the piston cavity diameter and the cylinder block kidney hole hydraulic diameter and the research results of the anticavitation of the valve plate triangular throttling groove, the optimized structure of anticavitation of the axial piston pump is proposed, and the simulation results show that the improved axial piston pump has better anticavitation performance.