粒状体ダンパの解析手法に関する研究

抄録

The particle damping system was investigated experimentally and theoretically. Particle dampers are passive damping devices and consist of a cavity partially filled with granular materials attached to a primary structure. The collision of granular materials with the wall of the cavity is results in an exchange of momentum and some energy dissipation of the primary system. Although their construction is simple and their effectiveness is essentially independent of temperature, particle damping is a very complicated phenomenon and remarkable nonlinear behavior. In this paper, a computational method for conducting simulations of particle damping was proposed. This method was based on the concept of an equivalent single-particle impact damper. The contact force model for representing the collision between a particle and the wall of the cavity was based on the work by Hertz, utilizing the theory of elasticity. In addition, the damping force was given, considering a fully plastic contact. The granular materials used in this study were glass beads and copper beads. Also, the mass ratio was set to 5% and 10% for glass beads and 10% and 15% for copper beads. The validity of the analysis method was verified by comparing the analysis results with the experimental results. It was found that an analytical solution is provided to estimate, with reasonable accuracy, the response of the primary system.