Control and reduction of friction-induced vibration in some industrial applications

The frictional behaviour of several combinations of industrial friction materials that are related to two specific applications was investigated experimentally and analytically. The objective is to gain knowledge on how to better control and eliminate, if necessary, friction induced vibrations in industrial applications. The materials studied exhibited either stick-slip or quasi-harmonic vibration. The friction-velocity characteristic has been proved to be a useful tool to predict the vibrational behaviour of a friction pair. In the quasi-harmonic case, a nonlinear analytical friction model based on an approximation technique, can predict the occurrence and the amplitude of friction-induced vibration when the system is submitted to a static normal load. The effect of dynamic normal loading on the frictional behaviour and on the occurrence of chaos has also been investigated. No chaotic motion was detected. Stick-slip vibrations can be extinguished by a normal loading with a small amplitude and a frequency close to the natural frequency of the system. In the case of quasi-harmonic vibration, it can be quenched and is replaced by a vibration with the excitation frequency and usually with a smaller amplitude than that of the quasi-harmonic vibration. Experimental, analytical and numerical results were all in good agreement for the quasi-harmonic type of vibration.Applied Science, Faculty ofMechanical Engineering, Department ofGraduat