Dynamic modeling of rolling bearing considering local defect edge topographies

When the rolling elements pass through the local defect area on the surface of the bearing raceway, there is a complicated contact process, which is closely related to the edge morphology and size of the defect. However, most of the existing studies use rectangular grooves through the raceway to simulate bearing defects, and it is relatively simple to describe the contact process between the rolling elements and local defects, without considering the influence of the edge morphology of the local defects. Therefore, taking the bearing outer ring fault as the research object, firstly, the displacement excitation and impact force action point change when the rolling elements contact with different defect forms are analyzed in detail. Then, based on the time-varying excitation function, a fault excitation function considering the influence of the local defect edge is proposed. Based on the above excitation function, a local fault dynamic model of the outer ring of the deep groove ball bearing is established, and the accuracy of the model established in this paper is verified by the measured signal. Finally, the influence of fault edge morphology on bearing vibration characteristics is analyzed and studied by using the dynamic model, so as to guide the condition evaluation of rolling bearing in practical application.