【作者】 李虎；

【导师】 孟利民； 崔建中；

【作者基本信息】 安徽理工大学 ， 机械工程， 2021， 硕士

【摘要】 作为一种新型的流体传动技术,液粘传动技术利用粘性流体的剪切作用传递动力,主要运用在如风力发电、盾构机和可控减速器等中、高端机械装备的柔性动力调节领域。液粘柔性传动可以有效减缓启动过程中的冲击,提高传动精度,延长零部件的使用寿命。因此,综合采用理论建模、数值计算和实验验证等方法对液粘调速离合器的柔性传动过程展开研究,主要内容如下:首先,深入分析了液粘柔性传动过程的微观摩擦机理,基于流体润滑理论与粗糙表面分形理论,通过承载力与转矩平衡原理对液粘柔性传动过程进行动力学建模。采用数值计算手段分析了柔性传动过程中油膜厚度、被动片角速度、输出转矩与粘性转矩等主要动力学参数的变化规律,最终获得了包括接合压力、润滑油粘度、分形维数等主要动力学参数对柔性传动动力学特性的影响规律。以传递效率最大化以及流体摩擦与混合摩擦时间占比最大化为优化目标,建立了关于液粘调速离合器柔性传动过程的优化模型。采用NSGAII进行求解计算,获得了液粘调速离合器传动效率以及流体摩擦与混合摩擦时间占比达到最佳时的摩擦副系统设计参数组合。经过优化设计,液粘调速离合器传动过程的效率与稳定性得到相应的提升。以优化设计结果为基础,对摩擦副热量的产生、传递及分配机制进行了分析。然后通过有限元分析得到了摩擦副多物理场的分布规律。由对比可知,优化后的摩擦副系统能够有效避免因温度过高或应力过大而导致的摩擦片永久性损坏,提高了摩擦片的使用寿命。搭建液粘调速离合器实验系统进行台架实验,研究输出转矩与接合压力、摩擦副内外径之比的关系以及优化设计前后离合器的输出转矩变化以及摩擦副表面温度、形变量的分布与变化情况。结果表明,实验结果与理论结果整体变化趋势相同,验证了所建理论模型与优化设计的合理性、可靠性。图63表17参76更多还原

【Abstract】 As a new type of fluid transmission technology,hydro-viscous transmission transits power through the shear action of viscous fluid.It is mainly used in the flexible power regulation field of medium and high-end mechanical equipment such as wind power generation,shield machine and controllable reducer.The fluid viscous flexible transmission can effectively reduce the impact in the starting process,improve the transmission accuracy and prolong the service life of the parts.Therefore,this paper comprehensively adopts theoretical modeling,numerical calculation and experimental verification methods to study the flexible transmission process of HVD.The main contents are as follows:Firstly,the micro-friction mechanism of the hydro-viscous flexible transmission process is deeply analyzed.Based on the theory of fluid lubrication theory and rough surface fractal theory,the dynamic modeling of the flexible transmission process is carried out through the principle of bearing capacity and torque balance.By numerical solution,the variation of oil film thickness,driven plate angular velocity,output torque and viscous torque with time is obtained.Finally,the influence of different parameters,including engagement pressure,lubricating oil viscosity and fractal dimension,on the dynamic characteristics of flexible transmission is analyzed by this model as well.In order to maximize the transmission efficiency and maximize the time proportion of fluid and mixed lubrication,an optimization model for the transmission process of HVD is established.The optimization result is obtained by using NSGAII.After optimization,the efficiency and stability of the transmission process are improved.Based on the optimal design result,the mechanism of heat generation,transmission and distribution of friction pair is analyzed.The finite element model of friction pair is constructed according to the finite element theory.Through the finite element analysis,the distribution of temperature,stress and displacement can be obtained.It can be seen that the optimized friction pair can effectively avoid the permanent damage caused by excessive temperature or stress and improve the service life of the friction pair.The experiment system of the HVD is set up to carry out experiments.The relationship between the output torque and engagement pressure,the ratio of inner and outer radius is studied,as well as the change of the output torque,the surface temperature and displacement of the friction pair before and after the optimized design.The results show that the overall variation trend of experiment results is the same as that of theoretical results,which verifies the rationality of the theoretical model and the reliability of the optimal design.Figure 63 table 17 reference 76更多还原