湿式离合器接合过程油膜厚度和转矩仿真

Simulations of oil film thickness and torque during wet clutch engagement process

湿式离合器的接合过程直接影响离合器的使用寿命及其工作性能。基于流体力学理论以及粗糙表面的弹性接触理论,建立了湿式离合器接合过程中油膜厚度和传递转矩的数学模型,利用Runge-Kutta数值积分法对数学模型进行耦合求解,得到控制油压、润滑油黏度以及摩擦材料渗透性对油膜厚度和离合器传递转矩的影响规律。结果表明:提高控制油压能够有效提升离合器接合过程中的传递转矩,并且能够缩短离合器的接合时间;随着润滑油黏度的增大或摩擦材料渗透性的减小,离合器接合过程中传递扭矩的响应速度变慢,这将会延长离合器的接合时间;润滑油黏度和摩擦材料渗透性对离合器接合过程的挤压和压紧阶段传递的转矩影响较大,但对粗糙接触阶段传递的转矩影响较小。

The service life and the performance of wet clutch are affected by the clutch engagement process.Based on the hydrodynamics theory and the elastic contact theory of rough surfaces,the mathematical models of the oil slick thickness and the transmission torque were established for the engagement process of wet clutchs.The mathematical models were solved by the Runge-Kutta method,then the influences of pilot oil pressure,lubricant viscosity and permeability of friction material on the oil film thickness and the transmission torque of wet clutch were obtained. The simulation results show that increase of pilot oil pressure can effectively improve transmission torque of wet clutch and cut down engagement process time of wet clutch,and as the lubricating oil viscosity increases or the permeability of friction material decreases,the response speed of transmission torque during the wet clutch engagement process slows down,and the clutch engagement time is prolonged. The lubricating oil viscosity and the permeability of friction material have a great effect on the transmission torque of wet clutch during the compression and compaction stage,but have little influence on transmission torque during the rough contact stage.