The mass Ratio's and the primary structure damping Ratio's effects on the dynamic characters of the MTMDs device

The traditional tuned mass damper(TMD), which is designed for suppressing undesired resonance peak or large vibration at certain frequency, is very sensitive to the little disturbance in the change of natural frequency of the primary structure or TMD or the change in the excitation frequency. Thus, the multiple tuned mass dampers (MTMDs) configuration is developed to conquer this problem. If the MTMDs is designed to control vibration at certain frequency, the natural frequencies of all the MTMDs should scatter around the controlled one. According to different designs of the MTMDs, the optimum frequency spacing and average damping ratio of MTMDs have been investigated thoroughly. Whereas it remains a question how the mass ratio of the MTMDs to the primary structure and the inherent damping in the primary structure affect the dynamics performance of the MTMDs. This paper uses a searching technique to find out the optimum parameters of MTMDs to minimize the maximum response amplitude of a main structure to which the MTMDs connect. After that, the frequency response curves, which are related to different sets of mass ratio and primary structure damping ratio with MTMDs and single TMD, are presented to verify the efficiency of the MTMDs. The robustness of MTMDs, subjected to the detuning effects of the MTMDs' tuned ratio, damping ratio and frequency bandwidth, is also studied. Keywords: MTMDs dynamic characters.