Bouncing behavior and dissipative characterization of a chain-filled granular damper

Abstract

We have experimentally investigated the bouncing behavior and damping performance of a container partially filled with granular chains, namely a chain-filled damper. The motion of the chain-filled damper, recorded by a particle tracing technology, demonstrates that the granular chains can efficiently absorb the collisional energy of the damper. We extract both the restitution coefficient of the first collision and the total flight time to characterize the dissipation ability of the damper. Two containers and three types of granular chains, different in size, stiffness and restitution coefficient, are used to examine the experimental results. We find that the restitution coefficient of the first collision of a single-chain-filled damper can linearly tend to vanish with increasing the chain length and obtain a minimum filling mass required to cease the container at the first collision (no rebound). When the strong impact occurs, the collisional absorption efficiency of a chain-filled damper is superior to a monodisperse-particle-filled damper. Furthermore, the longer the chains are, the better the dissipative effect is.

Self-propulsion of a grain-filled dimer in a vertically vibrated channel

“…Moreover, the dimer is able to respond to the plate’s vibration with various distinctive modes of self-propelled motion. This design is inspired by the earlier studies of a grain-filled bouncing ball on a vibrating or a static plate 19 – 21 , in which the coefficient of restitution and its resulting bouncing dynamics demonstrate rich dependence on the mass and size of grains inside the bouncing ball. In our work, we introduce an asymmetry to the dimer by differentiating the size of grains in the two balls, while keeping the total filling mass of grains as well as other mechanical properties in each ball identical.…”