Abstract：In order to study the damping mechanism of non-packed particle damper (NPPD) in depth, the analysis of energy variation and the damping mechanism of physical parameters are carried out successively based on the proposed double inertia mass equivalent model (DIMEM). Firstly, the DIMEM is described briefly with emphasis on the establishment of DIMEM, the differential equations of motion of DIMEM-SDOF structure and the experimental verification of model. Then, the periodic energy consumption index and the periodic momentum exchange index are defined. The damping mechanisms of different physical parameters are discussed based on the proposed index. Finally, the analyses of damping performance of NPPD under free vibration, resonant harmonic excitation and earthquake are carried out based on the DIMEM. The energy change rule and proportion in vibration control are discussed. The results show that the energy of the system is mainly dissipated by the interaction between particles. The damping performance of NPPD is affected comprehensively by energy consumption and momentum exchange. It is difficult to explain the variation law of damping effect only by analyzing the energy consumption. The vibration reduction effect and mechanism analysis of NPPD based on DIMEM is of great significance for further understanding of particle damper and parameter optimization.
