【作者】 彭玉兴；

【导师】 朱真才；

【作者基本信息】 中国矿业大学 ， 机械设计及理论， 2009， 博士

【摘要】 摩擦提升机是矿井生产的关键装备之一,而提升机上的摩擦衬垫与钢丝绳这一特殊摩擦副是其安全可靠运行的关键。本文在高等学校博士学科点专项科研基金的资助下,针对摩擦提升机衬垫与钢丝绳间的滑动摩擦问题,开展摩擦提升机衬垫滑动热-应力耦合行为研究,旨在寻求摩擦衬垫摩擦接触性能随工况变化的内在机理与规律,为研制高性能摩擦衬垫和保障摩擦提升机安全可靠运行提供理论支撑,进而有效避免高速过卷过放事故的发生。本文主要研究内容包括:建立摩擦衬垫非完全接触温度场;建立摩擦衬垫和钢丝绳低速滑动摩擦接触力学模型;在以上两个模型的基础上建立摩擦衬垫高速滑动热-应力耦合模型;采用有限元数值分析软件进行热-应力仿真试验,分析摩擦衬垫高速滑动时的温度场、应力场及其耦合行为;在模拟试验台上开展摩擦衬垫与钢丝绳滑动摩擦试验,验证理论模型的正确性。首先,通过热分析试验掌握了摩擦衬垫动态热物性能;理论分析了摩擦衬垫与钢丝绳间的动态热分配机制;结合钢丝绳绳股螺旋结构分析了摩擦衬垫与钢丝绳之间的螺旋接触特性;基于热传导理论,综合考虑摩擦衬垫动态热物性能和螺旋接触特性,建立了摩擦衬垫非完全接触温度场模型,并采用有限差分法进行数值求解;在模拟试验台开展滑动摩擦试验,验证了理论模型的正确性。其次,通过多频时间谱动态力学性能试验掌握了摩擦衬垫黏弹性力学性能随加载时间和加载频率的变化规律;结合黏弹性力学理论和摩擦接触力学理论,构建了低速滑动时摩擦衬垫与钢丝绳绳股间的摩擦接触力学模型,并对其进行理论求解;开展低速滑动摩擦模拟试验,验证了理论模型的正确性。最后,通过动态热机械性能试验研究摩擦衬垫动态热机械性能,掌握了其复合模量随温度和加载频率的变化规律,并通过回归分析建立了摩擦衬垫热黏弹性本构关系;通过热膨胀仪得到了摩擦衬垫线膨胀系数随温度变化规律;结合摩擦衬垫非完全接触温度场模型、摩擦接触力学模型和热黏弹性本构关系,建立了摩擦衬垫热-应力耦合模型,采用多场耦合有限元软件对其进行数值仿真;开展高速滑动摩擦试验,同步多点测量摩擦衬垫的温度和应变,并将试验测量结果与仿真结果进行比较分析,验证了热-应力耦合模型的正确性。更多还原

【Abstract】 A friction hoist is the one of the most important equipments in mine, and the special friction pair between friction lining and wire rope in friction hoist is the key to guaranteeing its safe and reliable operation. This dissertation was financially supported by Research Fund for the Doctoral Program of Higher Education of China. Aiming at the problem of sliding friction between friction lining and wire rope, the thermo-stress coupling behavior of friction lining is investigated to seek the intrinsic mechanism and variation of the friction contact properties with different operating condition, which will be beneficial to avoid the accident of overwinding and overfalling, develop new friction lining and consequently guarantee the safe and reliable operation of friction hoist.The main content of this study includes: the friction lining’s temperature field under the condition of non-complete contact, the friction contact between friction lining and wire rope with low-speed sliding and the thermo-stress coupling behavior. And the thermo-stress during the sliding process was simulated by the software of finite element analysis. Consequently, the temperature field, stress field as well as thermo-stress coupling behavior were studied. Furthermore, the sliding friction experiment between friction lining and wire rope was carried out on the friction tester to verify the theoretical model.Firstly, the dynamic thermophysical properties were obtained by the thermal analysis and the dynamic distribution coefficient of heat-flow was analyzed theoretically. And the helical contact property was analyzed by considering the strand’s helical structure. Moreover, the model of friction lining’s temperature field was set up under the condition of non-complete contact with wire rope, and the finite difference method was applied to solve this problem. Subsequently, the friction experiment was performed on the friction tester and the theoretical model was verified by comparison between the simulation results and the expermental results.Secondly, the variation of mechanical properties with loading time and frequency was gained by the mechanical experiment of multi-frequency time spectrum. Through combination of the theory of viscoelasticity and contact mechanics with friction, the contact mechanics with friction between friction lining and wire rope was established and solved theoretically. Furthermore, the sliding friction experiment was carried out on the friction tester, and the experimental results show that the theoretical model is correct. Finally, the dynamic mechanical properties of frictin ling were investigated by DMA and the variation of complex modulus with temperature and frequency was obtained. Besides, the thermoviscoelastic constitutive relation of friction lining was established by regression analysis. Taking into account the temperauture field with non-complete contact, stress field with sliding friction contact and thermoviscoelastic constitutive relation, the thermo-stress coupling model was established. Moreover, the numerical simulation was performed by multiphysics coupling software of finite element analysis. In the end, the temperature and strain at testing points were measured simultaneously, and the simulation results were compared with experimental results to verify the theoretical model of thermo-stress.更多还原