Flow pulsation characteristics of variable displacement piston pump considering coupling effects cavitation bubble and swash plate inclination angle vibration

Abstract

Variable-displacement piston pumps, in comparison with quantitative pumps, offer high volumetric efficiency, energy savings, and variable displacement advantages. The outlet flow pulsation of these pumps is influenced by several factors, including swash plate inclination angle vibration, cavitation bubbles, flow distribution structure, and valve control structure. This complexity poses challenges in accurately predicting the flow pulsation at the outlet of variable-displacement piston pumps. In response to this challenge, a novel outlet flow pulsation model for variable-displacement piston pumps is proposed, taking into account the coupling effects of cavitation bubbles and swash plate inclination angle vibration, building upon an existing model. Initially, the effects of cavitation bubbles and swash plate inclination vibrations on flow pulsation were analyzed. Subsequently, a comprehensive flow pulsation model for variable-displacement piston pumps was developed, considering the coupling effects of cavitation bubbles and swash plate inclination angle vibrations. This model was compared with three other existing flow pulsation models. The accuracy of the results was validated using a constructed test bench, with an accuracy improvement of approximately 12% compared to traditional theoretical models. Finally, an optimization model for outlet flow pulsation was proposed. The structural parameters of the valve plate, aimed at minimizing flow pulsation, were determined using the multi-agent particle swarm optimization algorithm. These findings underscore the importance of considering the coupled effects of cavitation bubble and swash plate inclination angle vibration in the design optimization process for reducing low-flow pulsation. This study provides a theoretical foundation for the design of variable-displacement piston pumps with minimized vibration and noise levels.