Numerical and experimental analysis in the energy dissipation of additively-manufactured particle dampers based on complex power method

An additively manufactured particle damper (AMPD) is a novel particle damper fabricated by deliberately leaving unfused powder inside the structure during the laser powder bed fusion (LPBF) process. It retains the advantages of a conventional particle damper, while yielding unique merits. However, the damping mechanism and performance of AMPD are still unclear owing to insufficient experimental and simulation analyses. This work focused on experimentally and numerically exploring the damping capacity of AMPDs at three different frequencies (200, 350, and 500 Hz) and an acceleration range of 150–300 m/s2. Two AMPDs with different numbers of unit-cells (64 and 27) were manufactured using LPBF with 316 L stainless steel. The complex power method is used to measure the energy dissipation of the AMPD in a straightforward manner. A numerical method based on the discrete element model of a previous study was proposed to predict energy dissipation in the simulation model. The developed numerical method was validated by comparing it with experimental data which showed good agreement. The influence of excitation frequency, excitation amplitude, and cavity size on the damping mechanism and performance of the AMPD was investigated using experimental and simulation methods. The results showed that the AMPDs had the highest damping performance at an excitation frequency of 500 Hz, and the motion mode of the internal particles was affected by the excitation intensity and cavity size, which play an essential role in the damping performance of AMPDs.