【作者】 谢方伟；

【导师】 侯友夫；

【作者基本信息】 中国矿业大学 ， 机械电子工程， 2010， 博士

【摘要】 液体粘性传动(简称液粘传动)是利用油膜的剪切力传递动力的一种新型流体传动形式,具有高效节能、无级调速、启动冲击小和同步传动等特点,在带式输送机、风机、水泵等大功率重载设备的调速启动方面有着广泛的应用前景,因此在我国开展液粘传动技术的研究具有极其重大的现实意义。针对目前研究中存在的问题,本文在以下几个方面进行了深入的研究。对工作油的粘度随温度的变化特性进行了实验研究,得出其粘温方程,研究了界面间温度分布特性;在此基础上推导出变粘度条件下无沟槽和有沟槽摩擦副间油膜压力、油膜的动压承载力和传递扭矩的解析解,并与常粘度条件下油膜的传动特性进行对比分析,揭示了温度对油膜传动特性的影响规律。基于热传导理论建立了混合摩擦状态下摩擦副瞬态热应力耦合场理论模型,确定了摩擦副间热流分配系数和热流密度,综合考虑热流密度、初始条件和边界条件,利用有限元法对所建立的瞬态热应力耦合场进行求解,得到了对偶片温度场和应力场的分布特性,分析了时间、对偶片厚度、摩擦衬片材料等因素对其影响规律,并利用CNC三坐标测量仪分析了对偶片的变形形式。建立了平行界面和变形界面间油膜的三维物理模型,利用计算流体动力学软件FLUENT进行数值模拟计算,得到了油膜温度场、压力场、速度场和流线分布特性,以及温度场、压力场沿径向和周向的分布规律,并得出温度场和变形界面对传递扭矩的影响规律。研制了专门的液粘传动实验台,通过大量的实验,研究了流量、转速差和变形界面对油膜温度场、压力场和传递的扭矩的影响;实验结果与理论分析基本吻合,证明了理论分析的正确性。研究取得的成果对液粘传动技术的深入研究具有指导意义,为液粘传动装置的设计和液粘传动技术的应用推广提供技术支持。更多还原

【Abstract】 Hydro-viscous drive (HVD) transmits power by using shear force of oil film, which is a new type of fluid power transmission, and has characteristics of high-efficiency and energy-saving, synchronous drive, small start impact and stepless speed regulation. HVD has tremendous potentials in a wide range of applications such as speed regulation and start in large belt conveyors, fans, and pumps. Therefore, it has great practical significance to carry out HVD technology research in our country. According to the existing problems, the following aspects are thoroughly researched in the dissertation.Variation of working oil viscosity with temperature is measured in experiment. The viscosity-temperature equation of the working oil is obtained. Based on the distribution of temperature between interfaces, the analytic solutions for pressure, dynamic load capacity, and torque transferred by oil film between friction pair with and without grooves are deduced. Compared with constant viscosity, the transmission characteristics of oil film are analyzed. The influence of temperature on oil film transmission characteristics is revealed.On the basis of heat conduction theory, a theoretical model of transient thermal stress coupling for steel disk under mixed friction stage is established. Heat flow distribution coefficient and heat flux between friction pair are determined. Combining heat flux, initial conditions and boundary conditions, the theoretical model is solved using finite element method, the distribution law of temperature field and stress field of steel disk are found. The influence of time, thickness of steel disk, and material of friction pair on temperature field and stress field are analyzed. The deformation style of the steel disk is measured by using CNC three-coordinate measuring instrument.3-D physical models of oil film between parallel interface and deformed interface are built. The models are calculated by using computational fluid dynamics software FLUENT in numerical simulation. The temperature field, pressure field, velocity field and the characteristics of streamline of oil film are obtained. The distribution law of pressure field and temperature field along radial and circumferential direction, and the influence law of temperature field and deformed interface on torque transferred by oil film are obtained.A special HVD test-bed is developed. Based on a large number of experiments, the influence of flow rate, rotational speed difference and deformed interface on temperature field, pressure field, and transferred torque is researched. The experimental results approximately agree with the theoretical analysis results and the validity of theoretical analysis is proved. The research results play a guiding role in the thorough research on HVD technology, and provide technical support for the design of HVD device and application and popularization of HVD technology.更多还原