Damper force characteristics of a separated dual-chamber single-rod-type damper using an elastomer-particle assemblage

•Separated dual-chamber damper using an elastomer particle assemblage was proposed.•The damper force shows a hardness-type damping characteristic.•The damper force has a hysteresis characteristic.•Damper force changes greatly depending on the packing fraction or the material.•Damper force changes with vibration frequency and piston stroke. In the present paper, the damper force characteristics of dampers using a particle assemblage instead of oil have been reported. A separated dual-chamber single-rod-type damper using an elastomer particle assemblage was produced. The effects of the packing ratio of the particles, the vibration frequency, and the materials of the particles on the damper force characteristics of the damper with elastomer particles only on one side chamber were investigated experimentally. The maximum damper force was found to increase as the packing ratio, the vibration frequency, or the Young's modulus of the material of particles increased and the hysteresis of the damper force increased, i.e., the damping energy increased. In order to visualize the behavior of particles inside the damper, numerical simulation using the discrete element method was carried out. The simulation results agreed qualitatively and quantitatively with the damping characteristics of the experimental results, and large hysteresis was found to appear in the damper force due to deformation of the elastomer particles.