【作者】 张世军；

【导师】 林腾蛟；

【作者基本信息】 重庆大学 ， 机械设计及理论， 2009， 硕士

【摘要】 过热是湿式多片摩擦离合器最常见的故障之一,在工程实践中受到广泛的关注。研究发现,离合器过热故障不仅在接排过程中会发生,在空转状态下也会发生,主要是由于摩擦片与对偶片分离不彻底产生滑摩会导致润滑油油温过高而影响正常工作。因此,研究离合器空转状态和接排过程的发热因素对解决离合器过热失效问题具有重要的工程意义。本文研究来源于重庆市科技攻关计划项目。针对船用齿轮箱中的湿式多片摩擦离合器,运用数值仿真方法研究空转状态油路结构的流场和接排过程摩擦片的瞬态温度场,进而为设计低发热、高寿命、高可靠的离合器打下基础。本文的主要研究工作如下:①综合考虑离合器的结构和使用工况,以油路中摩擦片间隙、喷油孔直径、润滑油入口流速、润滑油温度等为可变参数,建立了湿式多片摩擦离合器油路流场的参数化有限元分析模型。②利用ANSYS/FLOTRAN软件对离合器油路进行流场分析,研究湿式多片摩擦离合器的油路结构对摩擦片间润滑油压力分布的影响,基于仿真结果提出油路结构改进方案,并进行对比分析。③针对离合器的不同使用工况,进行油路的流场分析,得出不同工况下润滑油的油压云图和流速矢量图;进而研究入口流量和润滑油温度对摩擦片间润滑油压力分布的影响,并与试验结果进行比较。④构建了带径向油槽和螺旋油槽的摩擦片三维实体模型和瞬态传热有限元模型,分析了离合器接排过程,推导了摩擦片热流密度的计算公式,计算了摩擦片的对流换热系数。⑤应用ANSYS软件分析了离合器接排过程中摩擦片的瞬态温度场,得出接排过程中摩擦片的温度云图及最高温度随时间变化曲线,并研究了油槽宽度对摩擦片温度分布的影响。更多还原

【Abstract】 Overheating --- one of the most common causes of the failures of wet multi-plate friction clutches is concerned widely in the engineering practice. With study, it can be found that the clutch overheating failures happen not only in engaging process, but also in disengaged operation. Every time the friction plates and mating plates cannot separate absolutely, the lubricant’s overheating caused by the slipping friction between the friction plates and mating plates will happen, and the clutch’s normal work will be affected. Therefore, it has very important engineering values to research the heating factors of clutches in the process of engaging and disengaged operation to reduce overheating failures.The topic of this thesis is supported by scientific and technological project of Chongqing. Using numerical simulation method to study 3-D flow field of oil way and transient temperature field of friction plates of wet multi-plate friction clutches, the base of designing clutches with low-heat, long-life, high-reliability can be founded. The research work in this thesis can be summarized as follows:1) With comprehensive consideration of the structure and operating conditions of the clutch,the clutch friction plate clearance, squirt diameter, the lubricant velocity of clutch inlet and the lubricant temperature are set as variables , and then the parameterized finite model of oil way is established.2) The flow field of clutch is analyzed by the software of ANSYS/FLOTRAN, the influence of oil way structure of wet multi-plate friction clutch on the lubricant pressure distribution in the clearances between the friction plates is studied. Based on the result of simulation, the improved structure of oil way is given, and then the comparative analysis is carried out.3) According to the different operating conditions of clutch, the lubricant pressure contour and lubricant velocity vector graph are given after the flow field of clutch is analyzed. And then the distribution of lubricant pressure in the clearance of plates influenced by the inlet velocity and lubricant temperature can be studied, and compared with the test result.4) The friction plate solid and transient heat transfer finite model with spiral and radial oil groove is established, the engagement process of clutch are analyzed, the formula for calculating the heat flux is derived, and the convective heat transfer coefficient of friction plate is calculated.5) The transient temperature field of friction plate is analyzed by the software of ANSYS, the temperature contour and the curves of maximum temperature-time history of friction plate are given. And then the influence of the size of groove width on temperature distribution of friction plate is explored.更多还原