基于气液耦合原理的飞机液压系统流体脉动消振器

Attenuator for fluid pulsation in aircraft hydraulic systems based on gas⁃liquid coupling principle

飞机液压系统具有高可靠与高安全的需求,然而液压泵的输出流体脉动会导致管路振动,甚至元件损坏,是制约系统寿命和可靠性提升的瓶颈因素。机载液压系统对流体脉动抑制装置提出了宽频率范围、宽温度范围、高效减振、紧凑体积等要求,传统减振方式难以满足。从理论上给出了气液耦合消振数学原理,提出了一种宽频宽温的流体脉动消振器,用于飞机液压系统的脉动抑制应用。建立了该消振器的数学模型,研究了影响频率和温度范围的参数规律和设计准则,并讨论了安装位置的影响。研制了消振器样机,并针对航空液压泵开展了脉动抑制实验,验证了该消振器的宽频性能和宽温性能。实验结果表明,消振器在394.2~1540 Hz频率范围内有消振效果,且插入损失最大可达29.6 dB。常温下,压力脉动幅值时域上最大可降低75.7%,频域上最大可降低89.3%;高温下,压力脉动幅值时域上最大可降低68.0%,频域上最大可降低88.0%。提出的设计方法与消振器模型的有效性和准确性得到了实验验证,研制的消振器装置在宽频、宽温范围内具有良好的压力脉动衰减性能。

As high demands of reliability and safety for aircraft hydraulic systems,the flow ripples caused by the aircraft hydraulic piston pump may lead to pipe vibration and components’damage,which becomes the limitation of the high system reliability and long system lifetime.The attenuator utilized in the aircraft hydraulic system may demand wide frequency range,wide temperature range,effective attenuation effect and compact design,which are very challenging for the traditional attenuators.This paper presents the gas-liquid coupling principles theoretically,and proposes a novel fluid pulsation attenuator for wide range of frequencies and temperature.The mathematic model for the attenuator is established,and the design principles of the frequency range and temperature range are studied,and the positions of its installation are also studied.The prototype of attenuator is developed,and experiments are carried out on the aircraft hydraulic pump.The experimental results show that the attenuator has effective attenuation effect at frequency range from 394.2 Hz to 1540 Hz,and the largest insertion loss value could reach up to 29.6 dB.At ambient temperature,the reduction rate could reach up to 75.7%in the time domain and 89.3%in the frequency domain;at high temperature,the reduction rate could reach up to 68.0%in time domain and 88.0%in frequency domain.The principles and model proposed in this work are proven to be effective and accurate,and the attenuation effects are validated in wide range of frequencies and temperature.