摘要
以湿式制动器摩擦副为研究对象,在微观表面接触理论的基础上,考虑微凸体之间黏性力的影响,建立了微观摩擦表面的微凸体黏弹性侧接触模型;通过对微观模型的归一化和积分处理,推导了能反映微观模型参数特征的宏观轴向压力、转速及摩擦力矩关系的计算公式;获得了低转速时摩擦转矩-转速负斜率特性微观机理,分析了微凸体无量纲曲率和轴向压力两参数对负斜率动态特性的影响。结果表明,当轴向压力和无量纲曲率半径减小时,摩擦转矩变化率(dTf/dn)的最小值将会增大,摩擦转矩变化量减小,有利于降低摩擦副磨损。同时通过台架试验,复现了负斜率特性与相关参数间的作用关系。与试验测试对比,理论分析模型精度达到了86.82%,仿真结果准确。对进一步深入研究摩擦副摩擦性能和提高使用寿命,具有重要的理论研究意义。
Taking the friction pair of wet brake as the research object, based on the micro surface contact theory and considering the influence of viscous forces between the asperity, the asperity side-contact viscoelastic model of the asperity friction surface is established. By normalizing and integrating the microscopic model,the formulae for the relationship between the macroscopic axial pressure, rotational speed and frictional torque,which reflect the characteristics of the microscopic model parameters, are derived, and the microscopic mechanism of the negative slope of the frictional torque-speed characteristic at low rotational speeds is obtained. The results show that when the axial pressure and the asperity dimensionless radius of curvature are reduced, the minimum value of the frictional torque variation rate(dTf/dn) will increase and the amount of the frictional torque variation will decrease, which is beneficial to reduce the wear of friction pairs. At the same time, through the bench experiment, the relationship between the negative slope characteristics and related parameters is reproduced. Compared with the experimental test, the accuracy of the theoretical analysis model is 86.82%, and the simulation results are accurate. This is of important theoretical significance for further studying the friction performance and improving the service life of friction pairs.
作者
李杰
陈诚
王志勇
Li Jie;Chen Cheng;Wang Zhiyong(School of Mechanical-electronic and Automobile Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;Key Laboratory of Vehicle Transmission,China North Vehicle Research Institute,Beijing 100072,China)
出处
《机械传动》
北大核心
2023年第1期1-10,共10页
Journal of Mechanical Transmission
基金
国家自然科学基金(51675494)
北京建筑大学金字塔人才培养工程项目(JDJQ20200308)。
关键词
湿式制动器
摩擦转矩衰减
表面接触理论
摩擦副
黏弹性力
Wet brake
Friction torque attenuation
Surface contact theory
Friction pair
Viscoelastic force
