Energy Dissipation Model of Particle Dampers

Particle damping is a type of impact damping that is designed to mitigate the response of lightly damped structures under dynamic loading. It consists of granular materials constrained to move between two ends of a cavity in a structure. When attached to a vibrating structure, the collisions of individual particles with cavity boundaries result in a reduction in the vibration amplitude of the structure through momentum transfer. Particle damping with suitable materials can be performed in a wider temperature range than most other types of passive damping. Therefore, it can be applied in extreme temperature environments, where most conventional dampers would fail. Furthermore, it has distinct advantages, such as the use of a robust, simple-to-design and compact system. There is a considerable amount of descriptive data regarding particle damping. However, for a large number of parameters, such as particle size, cavity-filling fractions, material properties and cavity shape, it is extremely difficult to understand the damper performance. There have been some research studies on the development of analytical models to explain the complex phenomenon of particle damping using the discrete element method (DEM). DEM models can be used to simulate the response of dampers, but the prediction of the response is computationally very expensive. This paper presents the results of some numerical analyses of particle damping in the context of forced vibration in the vertical plane. First, the computational burden of DEM is examined. Then, a new energy dissipation model is represented. The validity of this method is examined by a comparison between experimental and calculated results.