Vibration Characteristic Evaluation of Nonlinear Vibration Systems With Gaps Considering Energy Dissipation by Collision

This paper deals with nonlinear vibration of a continuum system with gaps under random waves considered collision phenomena. In order to investigate this nonlinear vibration characteristic, experiments are made with an experimental apparatus consisting of a nonlinear vibration system. A 2.3mm thick plate is used for the collision phenomena experiments. Moreover, an analytical model of the cubic equation is proposed based on the restoring force characteristics in the experiments. This analytical model is used for the simulation analysis, and the results are compared with the experimental results. However, the Root- Mean- Square (R.M.S.) values of the response acceleration of the analytical results are larger than R.M.S. values of the response acceleration of the experimental result. The difference of these results indicates that energy is dissipated in the collision phenomena. Then, the coefficient of restitution by the collision phenomenon between mass and plate is measured from the experiments. In the analysis, the dissipation energy is replaced with an equivalent damping ratio. The simulations are calculated by using this modified analysis. Consequently, the simulation results agree well with the experimental results.