车辆综合传动电液换挡液压系统污染匹配研究

发布时间：2018-01-03 20:16

本文关键词：车辆综合传动电液换挡液压系统污染匹配研究　出处：《北京理工大学》2016年博士论文　论文类型：学位论文

【摘要】：油液颗粒污染物是影响和制约车辆综合传动电液换挡液压系统可靠性的关键因素之一。本文以电液换挡液压系统为研究对象,通过理论分析、数学建模、数值仿真和试验验证,研究了油液颗粒污染物特征及主要元件污染卡紧、污染磨损的失效机理,获得了敏感颗粒尺寸区间与匹配过滤精度;建立了动态过滤状态下的电液换挡液压系统污染控制数学模型,进行了污染控制方程的匹配仿真,研究了油液污染度动态平衡的变化规律及其影响因素,为电液换挡液压系统污染适应性设计与合理污染控制提供了依据。本文所做的主要工作如下:①应用多技术油液分析方法,研究了颗粒污染物的形貌特征、尺寸分布特征及成分特征;采用最大似然估计、模糊隶属度的稳健核主成分分析与正漂移Wiener过程等数学方法,将特征参数成功运用于电液换挡液压系统污染控制界限值的制定、磨损状态的分类与识别、劣化失效周期的随机过程预测,可实现电液换挡液压系统的视情维修,使得维护时间间隔延长。②应用滤饼过滤理论与塑性变形理论,建立了电液换挡阀阀芯污染卡紧力与运动副污染磨损寿命模型。污染卡紧力理论分析与试验结果的对比表明,阀芯处于平衡状态时,污染卡紧力是由滤饼对阀芯表面的摩擦力产生;随着推动力的上升,阀芯打破平衡状态,滤饼破裂导致污染卡紧力急剧减小。污染磨损寿命分析表明,阀芯阀体硬度差越小、运动副接触长度越短、阀芯直径越小,污染磨损寿命越长;油液污染度越高、大颗粒占比越高、工作油压和温度越高,污染磨损寿命越短。结合阀芯阀体配合副径向间隙变化规律,评估了电液换挡阀的颗粒污染物敏感尺寸范围及匹配过滤精度。③研究了齿轮泵端面间隙泄漏通道的颗粒破碎效应,以及压差流动与泄漏间隙变化规律,建立了齿轮泵性能劣化模型与寿命预测公式,获得了污染物浓度、流量劣化系数与容积效率的关系,分析了磨屑生成因子、平均过滤比、排量与结构参数、颗粒污染度等因素的影响规律。经过污染敏感度试验观测值与模型理论计算值比较,验证了理论计算比试验观测能够得到更稳健的结果即相同或更严格的污染敏感度。采用污染敏感度理论,获得了齿轮泵污染敏感极限尺寸及匹配过滤精度。④采用重复过滤因子?和重复污染因子?建立了过滤器的动态过滤模型,并根据综合传动液压润滑系统的污染控制框图,建立了单回路和多回路污染控制模型。以过滤器纳污容量和压差为约束条件,应用MATLAB/Simulink对电液换挡液压系统污染控制模型进行污染匹配仿真。仿真结果表明,污染度变化规律符合污染动态平衡理论;粗滤器与精滤器在整个时间历程中,压差与纳污量同时上升,据此预测了过滤器滤芯更换周期。电液换挡液压系统的污染匹配设计中,小的油液总体积和大流量对提高油液净化速率有利;过滤比在1???10范围内,污染平衡时间下降显著,一旦过滤比??20,影响极小。
[Abstract]:The particles of oil pollutants is one of the key factors affecting and restricting the vehicle integrated transmission electro-hydraulic shift hydraulic system reliability. In this paper, the hydraulic system of the electro-hydraulic shift as the research object, through theoretical analysis, mathematical modeling, numerical simulation and experimental verification, on the particles of oil pollution and pollution characteristics of main components of locking, failure mechanism the contamination wear, obtain sensitive particle size interval and matching filtering precision; a shifting mathematical model of hydraulic system pollution control electro-hydraulic dynamic filtration condition, simulation, pollution control equation, studied the changes and influence factors of oil contamination of dynamic balance, to provide the basis for the hydraulic fluid power shift adaptive design and reasonable system of pollution pollution control. The main works are as follows: 1. Analysis method of application technology of oil pollutant particle shape Features, distribution characteristics and composition size; maximum likelihood estimation using fuzzy robust kernel principal component analysis and process analysis is the drift of Wiener membership and other mathematical methods, the characteristic parameters applied to electro-hydraulic shift hydraulic system pollution control set limits, classification and recognition of wear state, stochastic process deterioration the forecast period, can realize the maintenance of hydraulic system of electro-hydraulic shift, the maintenance interval is prolonged. The application of filter cake filtration theory and plastic deformation theory, establish the life model of electro-hydraulic shift valve spool lock force and motion side wear. By comparing the results of pollution pollution card theory analysis and test result stress the valve in the equilibrium state, the contaminant lock force is generated by friction on the surface of the valve core of the filter cake; with the driving force of the spool rise, break the balance state, resulting in pollution of clamping force rupture cake Analysis shows that the pollution decreases sharply. The wear life, a valve core hardness difference is small, the shorter the length of contact pairs, the smaller the diameter of the spool, the contamination wear longer; oil pollution degree is higher, the higher the proportion of large particles, the working pressure and the higher the temperature is, the shorter life. Combined with the Contamination Wear of the valve spool with the variation of radial clearance, evaluated the electro-hydraulic shift valve size range, and sensitive particulate filtration. The effect of broken gear pump end clearance leakage passage of particles, and the differential pressure flow and leakage variation of gap, gear pump performance degradation model and life prediction formula is established, the pollutants the relationship between the flow concentration, degradation coefficient and volumetric efficiency, analysis of the wear debris generation factor, average filtering ratio, displacement and structural parameters, effects of contamination factors. After pollution sensitivity test Observation value is compared with the theoretical calculation model, theoretical calculation is proved by experimental observation can be more robust than the same or more stringent pollution sensitivity. The pollution sensitivity theory, the gear pump pollution sensitive limit size and matching filtering accuracy. Using double filtering factor and repeated pollution factors established?? the dynamic filter filter model, and according to the diagram of hydraulic lubrication system of integrated transmission of pollution control, the establishment of the single loop and multi loop pollution control model. To filter sewage volume and pressure as constraint conditions, the application of MATLAB/Simulink simulation, pollution of electro-hydraulic shift hydraulic system pollution control model. The simulation results show that the variation of the pollution degree meets the pollution dynamic equilibrium theory; coarse filter and fine filter in the course of time, pressure and quantity of pollutants rise at the same time, the prediction filter In the design of contamination matching of electro-hydraulic shift hydraulic system, small oil volume and large flow rate are favorable for improving oil purification rate. When the filtration ratio is in the range of 1?? 10, the pollution balance time decreases significantly, once the filtration ratio is 20, the influence is minimal.

【学位授予单位】：北京理工大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TH137

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