thesis fin

Recent studies have shown that an electric measurement made it possible to characterize the multi-contacts interfaces. The research initiated in granular media are transposed in a technological environment dedicated to monitoring and diagnosis of defects in bearings. This innovative method exploits the richness and sensitivity of a localized electrical measurement and correlated to the bearing load status. To demonstrate the potential of this method, experimental electrical measurements are performed on a bench and signal analysis reveals similarities with traditional monitoring methods. From a numerical point of view, the bearing is modeled with the discrete element method (DEM), usually dedicated to the study of granular media, from which the mechanical behavior of the bearing dynamic is well reproduced. Electromechanical formulation is then introduced to derive a numerical electrical quantity of a bearing in operation, compared with the experiment. Typical electrical signatures in response to complex stresses (defects, clearance, imbalance, etc.) are studied. Studies of the mechanical behavior of rings opens interesting perspectives to understand and model their damage. While many studies have been conducted on the vibration monitoring of bearings, the use of a localized electrical method without sensor is still untapped and has promising results.