射流偏转板伺服阀阀口冲蚀及阀特性变化的仿真研究

发布时间：2018-04-29 16:44

本文选题：射流偏转板伺服阀 + 冲蚀磨损　；参考：《兰州理工大学》2017年硕士论文

【摘要】：射流偏转板伺服阀具有可靠性高、结构工艺性好等特点,已广泛的应用于航空、航天等领域,有全面取代其他伺服阀的趋势。由于射流偏转板伺服阀内部油液流动复杂、流动速度高,使得射流偏转板电液伺服阀在高压射流时容易受到颗粒物的冲蚀磨损,导致其性能下降甚至产生故障。因此对射流偏转板伺服阀冲蚀磨损及其影响的研究对伺服阀寿命预测、故障分析具有重要的意义。本文运用理论分析与数值计算相结合的研究方法,针对某射流偏转板电液伺服阀工作时油液中的颗粒对其前置级及主阀的冲蚀磨损进行研究并就冲蚀磨损对伺服阀造成的影响进行分析。第一章,阐述了射流偏转板电液伺服阀冲蚀磨损及其影响研究的背景及意义,概述了两级电液伺服阀的发展历程及国内外射流偏转板伺服阀的研究现状以及冲蚀磨损的研究进展尤其是冲蚀磨损在液压领域的运用及发展。第二章,介绍了射流偏转板电液伺服阀的基本构成、工作原理。概述固液两相流中欧拉-拉格朗日方法并将其运用在射流偏转板伺服阀冲蚀磨损中,描述颗粒物在运动过程中所受到的力以及颗粒物的运动轨迹;将计算流体动力学与冲蚀磨损理论相结合对高速射流油液中颗粒对射流偏转板伺服阀前置级及主滑阀的冲蚀磨损进行数值模拟,预测冲蚀位置,计算冲蚀磨损率的大小并就不同尺寸的粒子对冲蚀磨损率的影响进行分析。第三章,针对射流偏转板伺服阀不同的前置级结构参数即射流喷嘴宽度、V形导流窗口夹角、射流盘厚度及偏转板厚度对前置级两接收孔压差以及冲蚀磨损率的影响进行分析;依据计算数值建立冲蚀磨损后伺服阀前置级的结构,对冲蚀磨损后的前置级流场进行数值计算,研究冲蚀磨损对偏转板伺服阀前置级接收孔压差及零位压力增益的影响。第四章,对冲蚀磨损前后的前置级两接受孔压差曲线进行拟合,获得两接收孔的压差与偏转板位移之间的关系;对射流偏转板伺服阀的各主要组成部分进行数学建模,采用AMEsim建立射流偏转板伺服阀的整体模型,将拟合曲线与AMEsim模型结合,研究冲蚀磨损前后射流偏转板伺服阀阀芯位移,空载流量的变化。最后,对本论文主要的研究工作及成果进行总结,对本研究中的不断完善和进一步研究的内容做了展望。
[Abstract]:The jet deflection plate servo valve has the characteristics of high reliability and good structural and technological properties. It has been widely used in aviation, aerospace and other fields, and has the tendency to replace other servo valves. Because of the complex flow and high velocity of oil in the servo valve of jet deflector, the electro-hydraulic servo valve of jet deflection plate is vulnerable to erosion and wear by particles, which leads to the deterioration of performance and even the failure of the valve. Therefore, the study on erosion and wear of jet deflector servo valve and its influence is of great significance to the life prediction and fault analysis of servo valve. In this paper, the method of combining theoretical analysis with numerical calculation is used. The erosion wear of the front stage and the main valve of a jet deflection plate electro-hydraulic servo valve was studied and the effect of erosion wear on the servo valve was analyzed. In the first chapter, the background and significance of the research on erosion and wear of electro-hydraulic servo valve with jet deflector are described. The development history of two-stage electro-hydraulic servo valve, the research status of jet deflector servo valve at home and abroad and the research progress of erosion wear, especially the application and development of erosion wear in hydraulic field are summarized. In the second chapter, the basic structure and working principle of electro-hydraulic servo valve of jet deflector are introduced. The Euler-Lagrangian method in solid-liquid two-phase flow is introduced and applied to the erosion and wear of jet deflector servo valve to describe the force and trajectory of particles in the course of motion. Combined with computational fluid dynamics and erosion wear theory, the erosion wear of front stage and main slide valve of jet deflector servo valve in high speed jet oil was numerically simulated, and the erosion position was predicted. The size of erosion wear rate was calculated and the influence of particles of different sizes on erosion wear rate was analyzed. In the third chapter, the influence of jet nozzle width and V shape flow guide window angle, jet disc thickness and deflection plate thickness on pressure difference and erosion wear rate of the two receiving holes in front stage are analyzed according to the different front stage structure parameters of jet deflection plate servo valve. According to the calculation value, the structure of the front stage of the servo valve after erosion wear is established, and the flow field of the front stage after erosion wear is numerically calculated, and the effect of erosion wear on the pressure difference of the receiving hole and the zero pressure gain of the front stage of the deflection plate servo valve is studied. In chapter 4, the pressure difference curve between the front stage and the two receiving holes before and after erosion wear is fitted to obtain the relationship between the pressure difference of the two receiving holes and the displacement of the deflection plate, and the main components of the jet deflector servo valve are modeled mathematically. The integral model of jet deflection plate servo valve was established by AMEsim. The fitting curve was combined with AMEsim model to study the change of valve core displacement and no-load flow rate before and after erosion wear. Finally, the main research work and results of this paper are summarized, and the continuous improvement and further research contents are prospected.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TH137.52

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