气压盘式制动器热—结构耦合仿真分析

发布时间：2018-04-03 19:22

本文选题：气压盘式制动器　切入点：热-结构耦合分析　出处：《武汉理工大学》2013年硕士论文

【摘要】：本文首先回顾了气压盘式制动器(ADB)结构设计与热弹性失稳现象研究的发展历程,对盘式制动器温度场与应力场的研究现状进行了综述。在此基础上,本文采用有限元法对制动器工作过程中制动盘与摩擦片间的热-结构耦合现象进行了仿真分析,并对制动器其他主要部件进行了强度与刚度校核。具体说来,主要包括以下几个方面： (1)热-结构耦合分析涉及到的基础理论简要分析。通过对接触分析理论、制动摩擦生热理论、传热学理论的分析,确定了制动摩擦热量在制动盘与摩擦片之间的分配关系,建立了制动器的三维瞬态导热微分方程并确定了相应的边界条件。最后,根据分析需要,选用商业分析软件ABAQUS作为热-结构耦合分析的求解器。 (2)紧急制动工况下制动器的完全热-结构耦合分析。首先选用商业分析软件HyperMesh作为前处理软件,建立了ADB热-结构耦合分析的网格模型；然后确定了热-结构耦合分析的热边界条件与位移边界条件,建立了ADB完全热-结构耦合分析模型,利用该分析模型对紧急制动工况下制动盘的温度场与应力场分布特征进行了分析。分析结果显示,制动盘的温度场与等效应力场均存在明显径向、轴向与周向梯度,高温区与高应力区均出现在制动盘面的摩擦半径附近。整个制动过程中,制动盘温度先升高后降低。制动盘的三向应力中,周向应力最大,周向应力是引起制动盘疲劳裂纹的主要原因。由于温度场与应力场的不均匀分布,制动盘会出现不均匀的热弹性变形,向内侧翘曲。 (3)制动盘的顺序热-结构耦合分析。为了研究制动盘在重复制动工况与持续制动工况下的温升情况,首先对制动过程中制动盘的机械应力进行了分析,分析结果显示,制动过程中,制动盘的机械应力很小,应力主要表现为热应力。在此基础上,采用能量折算法,建立了制动盘的顺序热-结构耦合分析模型,利用该模型对紧急制动工况、重复制动工况与持续制动工况的制动盘温度场与热应力场进行了分析。分析结果显示,在紧急制动工况下,采用顺序耦合分析方法得到的盘面温度与应力稍低于完全耦合法的分析结果；在重复制动工况与持续制动工况下,盘面温度均逐渐上升后趋于饱和；重复制动过程中制动盘温度与应力水平均较低；但在持续制动工况下,制动盘的温度与应力会上升到较高水平,持续制动工况下制动盘的热负荷较大。 (4)钳体与支架的机械应力分析。对制动钳体与钳体支架进行了静力分析,校核了钳体与支架在紧急制动工况下的强度与刚度,分析结果显示,钳体与支架均能满足使用要求。本文的研究可为气压盘式制动器的设计提供参考,同时也为开发具有自主知识产权的气压盘式制动器奠定了基础。
[Abstract]:In this paper, the development of structure design and thermoelastic instability of disc brake is reviewed, and the research status of temperature field and stress field of disc brake is summarized.On this basis, the thermo-structural coupling between brake disc and friction disc is simulated and analyzed by finite element method, and the strength and stiffness of other main parts of brake are checked.Specifically, it mainly includes the following aspects:1) A brief analysis of the basic theory involved in thermal-structural coupling analysis.Through the analysis of contact analysis theory, brake friction heat generation theory and heat transfer theory, the distribution of brake friction heat between brake disc and friction disc is determined.The three-dimensional transient heat conduction differential equation of the brake is established and the corresponding boundary conditions are determined.Finally, according to the need of the analysis, the commercial analysis software ABAQUS is chosen as the solver of the thermal-structural coupling analysis.2) complete thermal-structural coupling analysis of brake under emergency braking condition.Firstly, the commercial analysis software HyperMesh is selected as the pre-processing software to establish the grid model of ADB thermal-structural coupling analysis, and then the thermal boundary conditions and displacement boundary conditions of thermal-structural coupling analysis are determined.The ADB complete thermal-structural coupling analysis model is established, and the distribution characteristics of temperature field and stress field of brake disc under emergency braking condition are analyzed by using the model.The results show that the temperature field and the equivalent stress field of the brake disc are obviously radial, the axial and circumferential gradient, the high temperature region and the high stress region appear near the friction radius of the brake disc surface.During the whole braking process, the brake disc temperature rises first and then decreases.The circumferential stress is the largest in the triaxial stress of the brake disc, and the circumferential stress is the main cause of the fatigue crack of the brake disc.Due to the uneven distribution of temperature field and stress field, the brake disc will appear uneven thermoelastic deformation and warp to the inner side.The sequential thermal-structural coupling analysis of the brake disc.In order to study the temperature rise of the brake disc under the repeated braking condition and the continuous braking condition, the mechanical stress of the brake disc during the braking process is first analyzed. The results show that the mechanical stress of the brake disc is very small during the braking process.The stress is mainly expressed as thermal stress.On this basis, the sequential thermal-structural coupling analysis model of brake disc is established by energy conversion method, and the model is used for emergency braking condition.The temperature field and thermal stress field of brake disc under repeated braking condition and continuous braking condition are analyzed.The results show that the temperature and stress of disc surface obtained by sequential coupling method are slightly lower than those of complete coupling method under emergency braking condition, and under repeated braking condition and continuous braking condition, the temperature and stress of disc surface obtained by sequential coupling analysis are slightly lower than those of complete coupling method.The disc surface temperature increases gradually and then tends to saturation; the brake disc temperature and stress level are lower in the repeated braking process; but under the continuous braking condition, the brake disc temperature and stress will rise to a higher level.The heat load of brake disc is large under the condition of continuous braking.The static analysis of the clamping body and the clamping support is carried out, and the strength and stiffness of the clamping body and the support under the emergency braking condition are checked. The results show that both the clamping body and the support can meet the requirements of application.The research in this paper can provide reference for the design of pneumatic disc brake and lay a foundation for the development of pneumatic disc brake with independent intellectual property rights.
【学位授予单位】：武汉理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：U463.512

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