Normal Contact Damping Predict Model of Joint Surface Based On Unit Area and Fractal Theory with Simulation

摘要

Joint surfaces widely exist in mechanical assembly structures, the local stiffness and damping have important effect on the whole dynamic analysis of the structure. In this study, proposed a normal contact damping forecast model and analyze its damping characteristics, based on the microcosmic mechanism between joint surfaces and citing the domain extension factor and unit area radio, combine with the modified fractal theory and energy dissipation. The simulation results show that the damping characteristic curve appear inflection point when the fractal dimension value D is 1.428. When, the normal contact damping increases with the increase of fractal dimension but decreases with the increase of contact area. When, the normal contact damping increase with the increase of contact area. Since the reaction of real contact area is relate to the change of the load, the relationship between the normal contact damping and the contact area can accurately predict the performance of assembly structure to a certain extent, the existence of the inflection point also provide a reference for the optimization design of assembly structure.