A Study On Semi-active Flow-induced Vibration Control By Synchronized Switch Damping Method

With the development of the national aviation industry and civil engineering,the vibration and noise caused by the flow(FIV:Flow-Induced Vibration)has gained an increasingly attention from government and industries.The piezoelectric material has been widely used in the vibration and noise control for its excellent electromechanical coupling and frequency response characteristics.Usually,these vibration and noise are caused by the solid and sound excitation.Meanwhile,the synchronized switch damping method(SSD)based on the piezoelectric device has gained more attention from the aerospace industries.That's because this new method doesn't need complicated control system and huge energy requirement when compared with active control,and has better robustness and less sensitive to the environment when compared with passive control.In this paper,we first proposed the synchronized switch damping method to control the Flow-Induced Vibration,and studied the control effect.The experimental result showed that this method do have a good control effect on the FIV problem.In this paper,we mainly studied two normal FIV problem: vortex-induced vibration(VIV)and fluid elastic vibration.Firstly,we focused on modeling and analysis of the mechanism of these two phenomenon,and determined the materials and dimensions of the experimental model.Then,we used the synchronized switch damping method based on the voltage source(SSDV)to control the vortex-induced vibration of the structure.And the resonance frequency caused by the VIV was suppressed quiet well.Then,we improved SSDV method by adding amplitude judgment mechanism and adaptive voltage source method.And this improved method can also control the unstable vibration of the model under the changing velocity with a good stability.Finally,we used SSDV method to control the fluid elastic vibration of the structure.And the result showed that this method can have a good control effect on the stable vibration before divergence.And the improved SSDV method can also improve the critical wind velocity of the model.This research extends the application field of the SSD method,and provides a new method for the research and control of FIV problem.