Heat Flux in Friction Clutch with Time Dependent Torque and Angular Velocity

When a body slides over another body, the major part of the work done against the frictional force which resists the motion will appear as a heat at the interface between the contact surfaces of the bodies. Consequently, the temperatures of that interface will increase to high values and may cause a high thermal stresses enough to produce large thermal deformations and thermal cracks in the contact surfaces. The present paper presents an analytical solution to calculate the total heat generated between the rubbing surfaces for the dry friction clutch, the analytical solution was determined using the equations of motion of two-inertia system assuming a uniform pressure distribution over the surfaces of contact where in this case the heat flux will increase linearly with disc radius. The torque and angular sliding speed are dependent of time. The variation of torque and angular sliding speed with time were discussed through the first period of engagement (0≤t≤ts). The results showed that the values of the heat generated (heat flux) increases with disc radius where the maximum value appeared at the outer radius of the clutch disc. The maximum heat flux occurred at the mid time of slipping period (t=0.2s). In this research paper, it was assumed that the values of the relative angular speed decrease linearly with time of engagement.