A study on the energy dissipation mechanism of dynamic mechanical systems with particle dampers by using the novel energy method

Adding particles to mechanical elements can reduce their vibrations. Both the particles and the mechanical elements interrelate in a highly complex manner, thereby influencing the energy dissipation of the mechanical elements. The particle damping is extremely nonlinear, and the energy dissipation mechanism in such a granule–structure interaction system has scarcely been examined. This study aims to investigate the dynamic behavior and energy dissipation mechanism for a mass–spring–damper–slider system with a particle damper. A simple but robust energy method was first proposed to explore the energy dissipation mechanism, and a two-way coupled model of the discrete element method (DEM) and multi-body dynamics (MBD) was employed to analyze the complex interaction system. Three numerical benchmark tests and free vibration experiments for the system with a particle damper were conducted to validate the proposed energy method and the adopted coupled DEM–MBD model. Results show that the coupled DEM–MBD simulations reasonably agree with the corresponding experiments. The validated coupled model was subsequently employed to calculate the distribution of system energy, and to explore the effect of contact properties on the energy dissipation of the system during the free vibration process. In the mass–spring–damper–slider system with a particle damper, the damping effect resulting from particles is essentially caused by the contact forces generated when the particles make contact with the hollow box. The induced contact forces act as resistance forces to the hollow box, always do negative work, and suppress the motion of the hollow box. The energy loss of the particles primarily occurs through contact friction and contact damping when the particles are hit by the hollow box. Contact properties, such as friction and restitution coefficients, exhibit a negligible effect on the dynamic behavior of the hollow box, but substantially affect the distribution of energy dissipation in the particular system.