Damping of vibrations in a power transmission system containing a friction clutch

This paper presents a theoretical study of the process of damping of non-linear vibrations in a three-mass model of a power transmission system with a multi-disc flexible friction clutch switched on and off electromagnetically. Steady-state motion of the system is subject to harmonic excitation. The problem is considered on the assumption of a uniform unit pressure distribution between the contacting surfaces of the cooperating friction discs. Structural friction, small relative sliding of the clutch discs and linear viscotic damping have also been taken into account. In the case of sliding, the friction coefficient is not constant but depends on the relative angular velocity of slowly sliding discs. The aim of the analysis is to assess the influence of geometric parameters of the system, its external load, unit pressure, viscotic damping on resonance curves and phase shift angle of steady-state vibrations. The equations of motion of the examined system are solved by means of the slowly varying parameters (Van der Pol) method and digital simulation.