Evaluation of Energy Absorption in Nonlinear Vibration System With Gaps

Abstract

This paper deals with nonlinear vibration characteristics of a continuum system with collision phenomena under random waves with gaps. In order to investigate such a nonlinear vibration characteristic, an experimental apparatus consisting of a nonlinear vibration system was made. Moreover, we propose an analytical model based on the restoring force characteristics of the experiments. In this report, the size of the gap between a mass and a plate is set to 0.5mm or 1.0mm. For this experimental model we also propose an analytical model. We use plates of 1.6mm thickness in the collisions both in the experiment and the analysis. The analytical model is based on an elasto-plasticity solid model. When considering the coefficients of restitution or energy absorption, the experimental results nearly agree with the analytical results [10]. We found that the rate of a collision changes with the size of the gap at each input acceleration level. As the gap size widens, energy absorption decreases for each input acceleration level. Consequently, in order to increase the energy absorption, it becomes necessary to increase the rate of the collision.