Friction-induced vibration of wet clutches

The characteristics of friction-induced vibration of wet clutches were investigated based on a four-DOF dynamic model. The steady-state nonlinear LuGre friction model was employed. Stability analysis was performed by applying the eigenvalue method, the numerical simulation for the dynamic model was conducted with MATLAB/Simulink. The results demonstrated that the negatively sloped variation of friction coefficient with changes of relative sliding velocity and the fluctuation of interface pressure are the causes of clutch judder; under unsteady state, the larger the difference between static friction coefficient and kinetic one, the smaller the difference between the pressure fluctuation frequencies and unsteady modal frequencies, and the stronger the clutch judder; the resistance moment excitation has a similar effect to that of interface pressure fluctuation on clutch judder.