航空液压泵脉动压力的解析表达与级数展开

Analytic expression and series expansion of pulsation pressures of aviation hydraulic pumps

为了深入研究航空液压泵输出油液的脉动压力特性,以航空液压柱塞泵为研究对象,分析了柱塞泵运动和体积流量脉动的成因,推导了柱塞泵排油口的体积流量脉动函数表达式,建立了油液压力与体积流量脉动函数之间的联系,并采用傅里叶级数模拟了与实验数据吻合的多级脉动压力曲线。结果表明:模拟脉动压力曲线与实验数据基频、2倍频的相对误差均在5%以内,基频及2倍频处的压力幅值的相对误差均在1%以内,使用包含基频与2倍频的级数近似可以描绘航空液压柱塞泵出口处周期脉动压力的主要特征。研究结果为进行飞机液压系统管路结构的流固耦合振动仿真提供了载荷输入依据。

To deeply research the pressure pulsation characteristics of aviation hydraulic piston pumps, the movement of the pumps and the causes of volume flowrate pulsation were analyzed respectively. Furthermore the relationship between the oil pressure and the volume flowrate pulsation function was established,and the volume flowrate pulsation function expression from the pump discharge nozzle was deduced. Finally,the multistage pulsation pressure curves consistent with the experimental data were simulated through the Fourier series. The results showed that the relative errors of the simulated pulsating pressure curve and the experimental data were within 5%,and the relative errors of the pressure amplitudes at the fundamental frequency and the double frequency were within 1%. The series approximation including the fundamental frequency and the double frequency can be used to describe the main characteristics of the periodic pulsating pressure at the outlet of the aircraft hydraulic piston pump.The research results provide a load input basis for the fluid-structure interaction vibration simulation of the pipeline structure of the aircraft hydraulic system.