Research on flow ripple reduction of piston pump with pre-compression volume

The piston pump is a core power component of aviation hydraulic servo control systems, and its performance directly affects the overall efficacy of the hydraulic system. A significant challenge affecting the stability and control of hydraulic servo systems is the flow pulsation generated by the axial piston pump. This flow pulsation primarily arises from pressure fluctuations during the piston flow distribution process. To address this issue, a pre-compression chamber structure has been designed to achieve pre-boost and pre-depressurization of the piston, thereby enhancing the performance of the piston pump. Computational fluid dynamics (CFD) methods are employed to analyze the flow characteristics of the piston pump. Simulation results indicate that the pre-compression volume effectively pre-pressurizes the piston chamber, reducing the pressure differential between the piston chamber and the high-pressure outlet. This modification results in a reduction of approximately 12.3% in outlet flow pulsation for the bidirectional piston pump. This study provides a foundational approach for achieving stable flow output in piston pumps.