A novel hydraulic pulsation reduction component based on discharge and suction self-oscillation: Principle, design and experiment

Abstract

The reduction of fluid ripple in pipes is extremely important for the reliability and safety of aircrafts and ships. Currently, most researches only pay attention to the discharge port and ignore the suction port and the inherent characteristic of the axial pump between both ports, which may cause significant underestimation of fluid ripple especially in the closed-loop hydraulic system. Therefore, the aim of this study is to propose a novel passive fluid ripple attenuator, which can simultaneously reduce discharge and suction pulsation of the axial-piston pump, and adapt to the condition of frequent change of load reversing in closed hydraulic system. First, the phase matching rule is discovered between discharge and suction ripple, and then based on that, the proposed discharge and suction self-oscillation principle is verified through simulation on the phase relationship of the pump internal pistons, instead of considering the two separately as before. The attenuator designed with the concept of the discharge and suction self-oscillation principle is presented, and models of how ripple generates and the attenuator works are represented analytically. The corresponding simulation model is established, and the result indicates that the ripple of both ports of the piston pump is weakened significantly. Moreover, one testing platform is developed, and the experimental study is conducted on the discharge and suction ripple. It proves that the proposed attenuator based on discharge and suction self-oscillation principle can reduce the fluid ripple effectively.

A Novel 1D Approach for Modelling Gas Bladder Suppressors on the Delivery Line of Positive Displacement Pumps

“…However, the effectiveness of these systems can be optimised only in a specific range of working conditions, outside of them, their efficacy diminishes. An exemplary case illustrating this limitation is presented in Shang's research [9] where a spring accumulator is employed to attenuate the primary harmonic flow ripple produced by an axial piston pump. This mechanism exploits the pressure ripple characteristics of suction and discharge to enhance performance.…”

Application of a hydraulic gas bladder suppressor for pressure ripple reduction in gear pumps

“…These kind of devices are able to reduce the pressure ripple in relevant manner, a drawback is that they are bulky respect the pump size, another aspect to be evaluated is the compatibility with the implementation of condition-based maintenance relies on an effective prognostics and health management (PHM) system, whose function is to identify if and when maintenance action is required [12,13]. In [14], Shang employed a springtype accumulator to diminish the first harmonic of flow ripple generated by an axial piston pump. The suggested device leverages discharge and suction self-oscillation by utilizing the pump discharge and suction pressure ripple.…”

Theoretical Analysis of Active Flow Ripple Control in Positive Displacement Pumps

“…Passive methods contemplate fitting external devices, such as resonators, outside the pump. One major drawback of passive devices connected on a pump delivery line is that they usually are designed and set to operate in particular conditions, being effective only at certain pressures or against particular frequencies [12][13][14]. This means, for example, that if the pump shaft speed changes, these systems lose their effectiveness, with the pressure ripple frequency being determined directly by the pump rotational speed.…”

“…This means, for example, that if the pump shaft speed changes, these systems lose their effectiveness, with the pressure ripple frequency being determined directly by the pump rotational speed. In [13], a passive solution is proposed with the aim of reducing the pressure ripple both on the suction and on the delivery side; a particular flow ripple attenuator is presented and connected to suction and delivery lines.…”