524 強制振動をうける粒子ダンパの近似解析(衝撃・粒状体ダンパ,OS-3 ダンピング,総合テーマ「伝統を,未来へ!」)

抄録

Particle damper is a passive vibration absorber which attenuates response of a vibrating structure using small particles within cavities embedded in the structure. The damper is promising especially for harsh environments, but the damping mechanism is very complicated and highly nonlinear, compared to the conventional damping techniques. In this paper, the approximate analytical model is developed for the vertical forced vibration of the damper. The granular particle bed in cavity is modeled as a single body with effective coefficient of restitution which can wrap all energy dissipation mechanism for reasonable bed/layer thickness. Numerical simulations and theoretical analysis based on this model yields results which are in accord with the experimental observations for the adequate mass ratios, bed/layer thickness, number of particles, and excitation levels. With this as a basis, numerical studies were carried to predict the results obtained by discrete elements method.