湿式多片换档离合器带排转矩的预测模型

Drag torque prediction model of wet multi-disk shifting clutch

为了研究湿式多片换档离合器带排转矩的形成机理,建立湿式离合器的带排转矩预测模型.根据黏性流体力学中层流理论的Navier-Stokes方程,考虑到分离间隙中冷却润滑油膜的离心惯性作用,推导油膜的径向速度模型.通过对径向速度的仿真分析,揭示离心惯性力会使油膜产生收缩的现象.为了描述这一现象引入等效外径的概念,利用油膜的表面张力作用求出等效外径.将等效外径应用于牛顿内摩擦定律推导新的预测模型,通过试验数据和传统模型验证了新模型的正确性和有效性.

A new prediction model was presented to predict the drag torque of a disengaged wet clutch in order to analyze the formation mechanism of drag torque of wet multi-disk shifting clutch. A radial velocity model of the oil film was deduced according to the Navier-Stokes equation based on laminar flow of viscosity hydrodynamics and considering the centrifugal effect of cooling and lubricating oil film in clearance. Then the radial velocity was analyzed. Results showed that the centrifugal force caused the shrinking of oil film. The equivalent outer radius was introduced to describe the phenomenon, and was resolved by utilizing the effect of surface tension of oil film. A new model was derived by combining the equivalent outer radius with the Newton inner friction law. The correctness and effectiveness of the new model were verified by test data and traditional model.