Numerical simulation of vibration damping by granular materials

In recent years, there have been examples of efforts related to vibration reduction of plate vibration using granular materials, impact dampers, etc. On the other hand, as a means of analyzing the influence of the application of granular material on the vibration characteristics of the plate-shaped structure, it is currently said that little knowledge has been obtained. In this report, a simulation method of the damping effect of bending oscillation of the plate by granular material combining following two kinds of methods was proposed. One is the discrete element method (DEM) for analyzing the motion of the granular material. The other is the finite-difference time-domain (FDTD) method for vibration analysis of the thin plate. In this proposed method, influence of the granular material on the plate vibration was considered. Validity of the proposed method was confirmed by comparison between the results of the calculation and the model experiment. Then, this study confirmed the dependency of the damping effect of the plate vibration on the external excitation force caused by the granular material.