基于油膜动态特性的拖拉机湿式离合器摩擦副接合热行为研究OA

As the core power control component of the tractor transmission system,the transient viscous flow of the oil film between friction pairs and the thermo-fluid-solid coupling effect of the wet clutch during engagement directly determine transmission reliability and thermal stability.Aiming at the unclear mechanism of how the wet clutch oil film's dynamic characteristics affect friction pair temperature evolution,the fluid control and heat generation rules during engagement were analyzed,the dynamic mesh and thermal boundary constraints were studied,and a thermo-fluid-solid coupling model was established.Fluent simulated the friction pair engagement to obtain oil velocity,pressure,temperature and volume fraction distributions,revealing the transient heat generation and transfer mechanism.Wet clutch bench temperature tests were conducted with R2,RMSE and MAPE as indicators to verify the model's effectiveness in characterizing engagement thermal behavior.Results showed that oil velocity increased radially under centrifugal and shear forces;the middle-inner diameter zone had little oil,high pressure and poor lubrication,concentrating high temperature there with the peak at 75%radial depth of the steel disc and a radial temperature gradient.Tests verified the thermo-fluid-solid coupling model(R2=0.971,RMSE was2.11℃,MAPE was2.23%)had higher prediction accuracy than the thermo-solid coupling model(R2=0.931,RMSE was 3.47℃,MAPE was 3.00%).The research result revealed the oil film dynamics'regulation mechanism on heat generation and transfer,providing theoretical and technical support for tractor wet clutch structural optimization and transmission performance improvement.