湿式离合器流场与作用力模型试验研究

Model Experimental Study on Flow Field and Force of Wet Clutch

轴向和周向作用力影响湿式离合器宽速域范围工作性能。针对湿式离合器对偶片间带排转矩与轴向力演变问题,根据湿式离合器简化结构,开发湿式离合器模型流场可视化与受力测试试验装置。通过试验测试分析流场演变过程,得到对偶片间带排转矩与轴向力参数影响规律。结果表明,流场包括全液相流和气液分层流两种基本流型,在纯液相和纯气相区之间可形成一个稳定的边界。随着转速的增大、流量的减小和间隙的增加,对偶片间流场中的油液体积分数减小,两相边界向内侧移动。流量和间隙对带排转矩的拐点有显著影响,减小流量和增大间隙都可降低拐点对应的转速。随着转速增大、流量减小和间隙增加,对偶片间轴向力呈现下降趋势。在带排转矩拐点附近,轴向力的作用方向发生改变,且最终轴向力几乎减小到零。

Axial and circumferential forces affect the performance of the wet clutch in the wide speed range.Aiming at the evolution of drag torque and axial force inside wet clutch,according to the simplified structure of the wet clutch system,a model experimental device for the visualization of the flow field and the force test of the wet clutch is developed.The evolution process of the flow field is analyzed through the experimental test.The parameter effects on the torque and axial force is obtained.The results indicate that the flow field consists of two main flow patterns:the full liquid flow and the gas-liquid stratified flow.A stable boundary can be formed between the full liquid phase and the full gas phase.With the increase of the rotating speed,the decrease of the flow rate and the increase of the disk clearance,the oil volume fraction in the flow field decreases.The two-phase boundary moves inward.The flow rate and the disk clearance have a significant effect on the turning point of the drag torque.The reducing of the flow rate and the increasing of the clearance can reduce the rotation speed of the turning point.With the increase of the rotating speed,the decrease of the flow rate and the increase of the disk clearance,the axial force shows a downward trend.Around the turning point of the drag torque,the direction of the axial force changes.The axial force almost reduces to zero with the further increase of the rotating speed.