Flow Ripple Reduction of Axial Piston Pump for Multiple Working Statuses with Fast Structural Optimization Method

Abstract The flow ripple caused by an axial piston pump may lead to pipe vibrations and lower hydraulic component reliability, which are of particular concern in hydraulic systems. The valve plate of the pump is considered the part most related to flow ripple, and its structural design is an important topic. In this study, an analytical model for the axial piston pump flow ripple was established and verified using a numerical analysis with computational fluid dynamics (CFD) calculations. Moreover, a parametric analysis of the valve plate was performed to investigate the critical parameters and their ranges. A fast optimization method, the rotation vector optimization method (RVOM), was proposed for the valve plate design and compared with the currently used optimization methods to prove its efficiency. As a constant-pressure pump works in different states of swashplate angle, outlet pressure, and pump speed, an optimization principle for the entire working status was proposed to achieve the overall reduction performance. A test rig for an aircraft hydraulic pump was established, and validation experiments were conducted. It was determined that the optimized pump could achieve reduction at multiple working statuses, and the largest pressure pulsation reduction ratios for the typical speed and speed sweep tests reached 64.7% and 71.7%, respectively. The model and method proposed in this study are proven to be effective and accurate.