Performance Optimization of Three-Mass Nonlinear Rigid Impact Damper by Hybrid Metaheuristic Method in Free Vibration

The aim of the present study is to reduce the free vibrations of a mechanical system by optimally designing the mass ratio of a nonlinear damper called the impact damper. The impact damper contains a number of masses connected to the main system that has the ability to move in a closed enclosure and reduce the amplitude of the main system through the transmission of motion. According to research done so far, impact dampers have better performance in reducing vibrations than linear dampers. The most important factor in the optimal performance of this damper is the design of the mass ratio. Due to the complexity and high volume of calculations to analyze the behavior of an impact damper, in this study, the hybrid metaheuristic method has been applied to determine the mass ratio. By comparing the results of the presented optimization method and the conventional design, the high power and efficiency of the proposed method for damper design are evident. The optimal design of problem parameters could reduce the amplitude of system vibrations in less than 2 seconds to 5% of the initial amplitude. The application of optimal impact damper has also decreased the system energy by more than 90%