先导式压力控制阀自激振动及其噪声研究

发布时间：2019-05-12 00:45

【摘要】：液压系统中,液压元件振动是破坏液压系统正常工作的根源,而自激振动是先导式压力阀振动的三大主要振动之一。先导式压力阀的自激振动及其噪声主要来源于先导阀,因此开展压力阀自激振动研究具有十分重要的意义。本文通过分析先导式压力阀的结构特点,建立了先导式压力阀都具有的锥形阀芯先导阀模型。分析了影响先导阀稳定的因素,并利用Bode稳定性判据对先导阀进行稳定性判断,结果表明:本文中所研究范例先导阀开环稳定,闭环不稳定;基于流体对阀芯的影响,对阀芯受到流体流动诱发振动进行理论分析,并对不同阀腔结构参数下流场进行仿真分析,先导阀前腔阻尼孔偏心和先导阀出口接近阀口都不利于先导阀稳定;通过对先导式溢流阀进行仿真分析,得到了先导阀芯振动的频域特性,先导阀芯振动频率在100Hz至1500Hz之间,500Hz左右振幅出现最大峰值,在700Hz至800Hz之间振幅出现次大峰值,其次在100Hz至300Hz和500Hz至700Hz频率段振动幅值波动剧烈。对溢流阀阀体模型进行了模态分析和基于先导阀阀芯自激振动激励下的谐响应分析,阀体约束越多连接刚度越高越有利于压力阀的稳定,仅约束进出油口时阀体在600Hz左右出现谐振峰值,且该工况下第一阶固有频率为638Hz,约束阀体三个进出油口时阀体第一阶固有频率较高,且在0~1200Hz频率段激励下振动平稳。通过对Y-10B型先导式溢流阀自激振动和辐射噪声进行试验,得到了溢流阀在不同压力下的振动和噪声辐射特性,随着压力的增大振动加剧,阀体振动的峰值频率也增多,并且噪声辐射强度随之增大。
[Abstract]:In hydraulic system, the vibration of hydraulic components is the source of destroying the normal operation of hydraulic system, and the self-excited vibration is one of the three main vibration of pilot pressure valve. The self-excited vibration and noise of the pilot pressure valve mainly come from the pilot valve, so it is of great significance to carry out the research on the self-excited vibration of the pressure valve. Based on the analysis of the structural characteristics of the pilot pressure valve, the conical core pilot valve model of the pilot pressure valve is established in this paper. The factors affecting the stability of the pilot valve are analyzed, and the stability of the pilot valve is judged by Bode stability criterion. The results show that the pilot valve studied in this paper is stable in open loop and unstable in closed loop. Based on the influence of fluid on the valve core, the vibration induced by fluid flow is analyzed theoretically, and the flow field under different valve cavity structure parameters is simulated and analyzed. The eccentricity of the damping hole in the front cavity of the pilot valve and the proximity of the outlet of the pilot valve to the valve port are not conducive to the stability of the pilot valve. Through the simulation and analysis of pilot relief valve, the frequency domain characteristics of pilot valve core vibration are obtained. The frequency of pilot valve core vibration is between 100Hz and 1500Hz, and the maximum amplitude of about 500Hz appears, and the second largest amplitude appears between 700Hz and 800Hz. Secondly, the vibration amplitude fluctuates sharply in the frequency range from 100Hz to 300Hz and from 500Hz to 700Hz. The modal analysis of the relief valve body model and the harmonic response analysis based on the self-excited vibration excitation of the pilot valve core are carried out. The higher the connection stiffness of the valve body constraint, the more favorable the stability of the pressure valve. The first order natural frequency of the valve body is 638Hz when the inlet and outlet is confined, and the first order natural frequency of the valve body is 638Hz under this condition. The first natural frequency of the valve body is higher when the three inlet and outlet ports of the valve body are confined, and the vibration of the valve body is stable under the excitation of the 0~1200Hz frequency segment. By testing the self-excited vibration and radiation noise of Y-10B pilot relief valve, the vibration and noise radiation characteristics of relief valve under different pressure are obtained. With the increase of pressure, the peak frequency of valve body vibration is also increased. And the noise radiation intensity increases.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH137.521

【参考文献】