Journal of Applied Mechanical Engineering

Friction-induced vibrations in a brake-like mechanical system

4^th International Conference and Exhibition on Mechanical & Aerospace Engineering

October 03-04, 2016 Orlando, USA

Oueslati Abdelbacet

Lille University of Science and Technology, France

Posters & Accepted Abstracts: J Appl Mech Eng

Abstract:

This work is concerned with new surface waves induced by friction instability and crossing the interface between an elastic thickwalled tube and a rotating rigid shaft modeling a brake-like system. Unilateral contact and dry Coulomb friction with a constant coefficient of friction act along the interface between the solids. A+ semi-analytical approach giving rise to a set of non-smooth reduced equations is adopted. This reduced system of the displacement and stress fields on the contact boundary is solved almost analytically and enables the construction of various families of traveling interface waves involving slip, stick and separation phases. Undoubtedly, stick-slip phenomena are the most famous and studied self-excited vibrations. Usually the propagation of contact waves is accompanied by noise emissions. Many examples are common in daily life such as violin sound, creaking door, noise of chalk against a table, brake squeal, and silo music (sound emission during the flow of granular materials through silos). In many industrial applications, stick-slip self-excited oscillations are harmful and may alter the performance of mechanical systems. The present work aims to provide: A detailed semi-analytic parametric study illuminating the influence of mechanical and geometric parameters on the stick-slip waves, new family of non-trivial solutions of overshooting stick-slip waves and new semi-analytical solutions of crossing slip waves. Moreover, the main characteristics of the obtained waves such as the wave number on the circumference, wave celerity, stick and slip proportions and contact stresses are delivered. Moreover, surface waves involving local separation zones are studied.

Biography :

Email: abdelbacet.oueslati@univ-lille1.fr