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1.
为满足煤矿井下作业严格的防爆要求,使盘式制动器摩擦制动过程中制动盘各点温升相等,分析推导盘式制动器摩擦片形状及其固定方式。  相似文献   

2.
汽车气压盘式制动器瞬时温度场研究   总被引:3,自引:1,他引:2  
华林  向上升 《润滑与密封》2007,32(5):8-11,29
基于盘式制动器制动过程中能量耗散的研究,建立了紧急制动过程中制动盘与摩擦片瞬态温度场分析的有限:元模型。采用直接热力耦合有限元方法来分析制动器摩擦热的产生及其温度的瞬态分布。结果表明,摩擦片与制动盘的:最高温度和达到最高温度的时间都不一样,摩擦片的温度从内径到外径基本是升高的,制动盘表面温度是中间部分最:高,内外径表面温度相对较低。与间接热力耦合方法相比,直接热力耦合方法考虑了制动器温度场与其应力应变场的瞬;态交替影响,使温度场的研究结果更接近实际工况。  相似文献   

3.
制动时间对起重机制动器温升的影响研究   总被引:1,自引:0,他引:1  
根据起重机盘式制动器的工作特点以及制动盘与摩擦片的实际几何尺寸,运用ABAQUS软件建立了三维摩擦生热有限元模型。有限元模拟过程中通过设定不同的制动时间,获得了不同的摩擦片温度场分布情况,并根据仿真结果,提出了控制制动器温升的对策。  相似文献   

4.
袁琼  李仕生 《机械强度》2020,42(5):1191-1197
建立起盘式制动器三维热-机耦合有限元模型,分析在拖曳制动和启停制动两种模式下制动器的热-耦合特性和摩擦振动特性,并探讨了在启停制动模式下,不同的减速行为对热-机耦合和振动特性的影响。结果表明:制动器在热-机耦合作用下,制动盘两侧摩擦片的热变形形式完全不同,导致两侧摩擦片的温度分布差异显著,活塞侧的摩擦片表面温度大于钳指侧摩擦片温度,这种温度差异也表现在制动盘两侧的盘面温度上;随着摩擦界面温度升高,制动系统的振动强度逐渐降低,但由于温度差异导致制动盘两侧的热变形程度不同,因此制动器活塞侧的振动强度大于钳指侧的振动强度;制动盘的减速行为对系统的热-机耦合特性和摩擦振动特性影响显著,在快速制动模式下制动器与外界热交换效应显著,界面温度较低,但是振动强度较大;慢速制动和分步制动模式下,界面温度迅速升高,但是由于摩擦过程较为缓慢,系统振动强度较低;尤其是分步制动的情况下,在某一阶段的振动强度有可能非常微弱。以上研究结果对认识制动系统的温度分布特性和改善制动器振动噪声问题具有一定指导意义。  相似文献   

5.
首先探讨盘式制动器在制动过程中的摩擦接触和非线性动力学问题.具体的分析方法包括:摩擦接触算法,非线性有限元方法.按照制动盘与摩擦片的实际几何尺寸,建立了具有速度可变效应的三维瞬态结构应力有限元模型,利用非线性有限元方法,较真实地模拟了制动器的制动过程.通过以上分析得出制动过程的一些结构上的性能变化.将同相同制动条件下的实心盘式制动器和通风盘式制动器对比,得出通风盘式制动器在制动过程中的接触应力,各向位移等.  相似文献   

6.
盘式制动器瞬态温度场的数值模拟   总被引:7,自引:0,他引:7  
对盘式制动器的温度杨进行数学分析;充分考虑制动器边界条件的实际情况,使用有限元软件模拟出制动过程中制动盘的三维温度扬,揭示制动盘上温度分布规律和温度梯度分布规律。为盘式制动器的设计提供理论指导。  相似文献   

7.
防爆力矩可调型盘式制动器是煤矿上大倾角下运带式输送机的关键设备,制动盘制动过程的温升直接关系到煤矿安全。本文用动态方法模拟制动盘温度变化过程。以便为制动器设计和安全使用提供理论依据。  相似文献   

8.
凭借热稳定性好、制动力平稳的特点,盘式制动器已广泛运用于各式车辆。由于盘式制动器制动时为摩擦制动,其热-结构耦合特性对制动器的结构、寿命有着重要影响。使用CATIA软件建立简化的三维结构模型,并通过ABAQUS模拟制动器的制动过程,模拟了制动盘在紧急制动过程中热-结构耦合特性的情况,确定了在制动过程中制动盘最容易发生热疲劳失效区域,并通过对制动盘表面径向及同一半径处的周向节点温度及应力的变化情况对比,深入分析了制动盘的温度及应力变化特性。利用Manson-coffin公式对制动盘在紧急制动工况下热疲劳寿命进行预测。  相似文献   

9.
随着我国经济水平的提高,汽车工业逐步发达,车辆的保有量不断增加,造成交通事故的频频发生,因此汽车的安全性越来越受到人们的重视。汽车制动器由温度产生的疲劳破坏是事故频发的诱因之一。通过有限元软件Abaqus对模拟结果分析得到制动器制动过程中温度及应力分布规律,最后通过改变有限元模型及边界条件并进行对比分析得到制动盘温度的升高是产生高热应力的最主要因素且制动盘尺寸对热应力分布有着重要影响,这也为制动器结构的设计和改进及摩擦片材料的选取及研制提供了参考和理论依据。  相似文献   

10.
张华 《机械管理开发》2020,35(9):143-145
矿用带式输送机的盘式制动器对整机系统进行制动时,制动盘与安装机架之间会产生振动效应,当制动盘与机架振动频率接近时会产生共振现象,将对整个制动器的制动性能有较大的影响。针对这个问题,以西南地区某矿盘式制动器为例,根据制动盘与闸瓦的前8阶模态分析结果对整个盘式制动器的结构进行优化,避免因制动盘与机架振动频率接近而产生的共振现象。优化结果显示,对整个盘式制动器的结构优化后有效避免了制动盘与机架产生的共振现象,提高了制动器制动性能,确保了带式输送机运行的安全性和稳定性。  相似文献   

11.
This paper presents a methodology for the modeling of the transient thermal behavior of the disk brake of the vehicles using finite element methods. The influence of the wear properties of friction materials on thermoelastic behaviors is investigated to facilitate the conceptual design of the model. The coupled characteristics of the friction heat flow between the disk and pad as well as the effects of the brake disk thermal stress because of the variable applied pressure was considered. At the same time, the model was optimized by the experiment. Repeated brake processes with varying load, sliding speeds and temperature are applied in the simulation of the disk brakes. Experimental dependencies of the coefficient of friction and wear rate on the temperature of brake pad were approximated and applied to the model. The temperature and pressure on the contact surface of the pad/disk brake system obtained for constant and speed/pressure sensitivity applications were confronted and compared. The thermo-distribution is operated to visualize the disk temperature.  相似文献   

12.
对有机石棉和半金属衬片材料与不同化学组分的灰铸铁制动盘(鼓)进行摩擦性能试验。分析了对偶材质对衬片磨损及摩擦系数的影响及衬片材质对制动盘(鼓)磨损的影响。提出了评定衬片材料的耐磨性必须标明对制动盘(鼓)的损伤及制动副材料的最佳选配问题。  相似文献   

13.
A numerical solution of the heat-friction problem for a brake pad–brake disk system during repeated intermittent braking has been obtained using the finite-element method. The obtained temperature field has been used to study the thermal stress state of the disk. A numerical analysis has been carried out for a metal-ceramic pad–cast iron disk friction pair during ten intermittent brakings. The effect of the coefficient of the coefficient of heat transfer on the temperature, the stress tensor components, and the Huber–Mises–Henky stresses on the working surface of the disk has been investigated.  相似文献   

14.
建立了盘式制动器中摩擦块-制动盘系统的有限元模型,选择合理的工况对其进行瞬态动力学分析,通过仿真模拟出粘滑运动,并对其产生机理及特性进行分析.通过仿真分析得到各参数对颤鸣特性的影响:活塞压力的增大、制动盘切向初速度的减小、动静摩擦系数差值的增大,都会对摩擦块-制动盘之间的摩擦力产生影响,从而使振动增强.  相似文献   

15.
为探讨碳/陶制动盘与不同闸片材料的匹配性,对碳/陶制动盘分别与碳/陶复合闸片、铜基粉末冶金闸片和铁基粉末冶金闸片组成的摩擦副进行制动试验,研究了在制动过程中盘面各点瞬时温度、最高温度、闸片温度与制动工况的关系。结果表明:碳/陶制动盘与碳/陶复合闸片摩擦副温度及温度梯度均高于其他2种摩擦副,其温度梯度在低速制动时随压力的增加而明显增加,当制动速度较高时,温度梯度并没有随压力的增加而增加;对于碳/陶制动盘与铜基和铁基粉末冶金闸片摩擦副,随制动速度和压力的提高,盘面温度梯度变化不明显。原因在于材料导热性和起始摩擦因数决定了盘面的散热能力和制动功率,碳/陶制动盘与碳/陶复合闸片摩擦副因较高的起始摩擦因数以及较低的导热性,其制动功率高和散热能力低,导致盘面温度持续升高。  相似文献   

16.
The objective of this study was to investigate the influence of an advanced performance system on the tribological behavior of brake pad material using a specially designed brake pad tester system following standard SAE J-661. The tribological behavior and friction and wear characteristics of the organic brake pad samples were evaluated. During braking tests, the samples, in contact with a cast iron disk, were studied at different disc speeds, temperatures, and braking cycles under a constant pressure. In order to understand the friction and wear behavior, the unworn surfaces, worn surfaces, and wear debris were characterized by means of scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). Furthermore, the surface characteristics and differences in the wear modes of the brake pad samples were examined. Wear debris was permitted to deform the brake pad surfaces, leading to friction layers and enabling the estimation of the friction behavior of the brake pads. The results showed that the best friction–wear behavior was obtained with lower braking cycles at low speeds and temperature. Thus, the newly developed brake pad tester system proved very effective in evaluating the performance of the brake pad samples.  相似文献   

17.
摩擦块形状对制动盘摩擦温度及热应力分布的影响   总被引:2,自引:0,他引:2  
列车制动产生的摩擦热在制动盘表面的分布与闸片结构密切相关,并影响到制动盘的耐热疲劳程度.基于实际应用的圆形、六边形、三角形3种形状摩擦块的制动闸片,利用有限元分析软件ABAQUS,模拟制动时制动盘的温度及热应力分布情况.结果显示:制动盘摩擦表面温度及热应力呈环形带状分布,沿周向变化不明显,在径向上分布的均匀程度差异较大;其变化程度与摩擦块形状和位置有关,摩擦块为圆形时,盘面的温差和热应力最小,摩擦块为三角形时,盘面的温差和热应力最大;摩擦块的位置分布影响到摩擦副接触弧长度,接触弧长度增加,对应的摩擦环带温度升高;各环带对应的接触弧长度偏差越小,制动盘温度越低,分布也越均匀.  相似文献   

18.
Generally, the thermoelastic instability (TEI) theory, which considers disk critical speed as one of the most significant factors, is used for investigating judder vibration. However, since the solution of judder problems by the TEI theory requires numerous assumptions, the experimental and the TEI results do not agree well. In addition, during experiments the critical speed varies with the pressure between the disk and the pads. In this study, for a TEI analysis, critical speeds of the disk brakes are obtained by using Hotspotter TM , and the experimental critical speeds and the number of hot spots are obtained with a chassis dynamometer and IR camera. Pressure distributions of the brake pad are calculated by a finite element analysis (FEA). Regression analysis and linear interpolation are performed to find the correlation between the experimental results for pressure of the master cylinder, the pad arc length, and the two disk specimens. The results show that the pressure interpolation results of the experimental equation have significant effects on the TEI analysis results.  相似文献   

19.
N.S.M. EL-Tayeb  K.W. Liew 《Wear》2009,266(1-2):275-287
In this work, dry and wet continuous sliding performances of newly developed four different non-commercial frictional brake pad materials (NF1, NF2, NF4, and NF5) were evaluated and compared with other two chosen commercial brake pad materials (CMA and CMB) using a small-scale tribo-tester of pad-on-disc type.Results showed that under dry continuous braking, friction coefficients for all non-commercial brake pad materials including the CMB were insensitive to the type of brake pad materials. In addition, all brake pad materials showed a slight increase in the friction coefficients (5–19%) with increasing pressure or speed. Meanwhile, the wear rates were substantially dependent on the type or ingredient of brake pad materials and the pressure. Conversely, under wet sliding condition, the friction coefficients were decreased by a factor of 2. Moreover, no evidence of HD water film could be evidenced as the measured friction coefficient values were in the order of dry friction. Thus, the wet results suggested that the friction behaviour was influenced by factors other than HD film, and the values of friction coefficient were in the range of dry friction, mixed and boundary lubrication friction. Qualitative assessment of the SEM morphologies of brake pad surfaces showed that tribofilms were easily formed in dry braking and hardly formed in wet braking. Besides, all brake pad rubbing surfaces showed contact plateaus “patches” and disintegrations of various sizes and locations depending on the braking condition. Furthermore, the removal of material was associated with either mechanical crushing action performed by entrapped wear debris or due to disintegration of plateaus which were accelerated by spraying the water.  相似文献   

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