AN EXPERIMENTAL STUDY ON ADDED MASS COEFFICIENT OF VORTEX- INDUCED VIBRATION OF A CIRCULAR CYLINDER

In this paper, an experiment study with aspect ratio 100 of a circular cylinder was conducted in a wave-current channel. The FBG sensors were attached on the circular cylinder which are used to capture vibration signal, two high-precision bellows type sensors were used to monitor fluctuant support force, and the dynamic response of circular cylinder was finally calculated by modal analysis method. The effect of flow velocity, mass ratio and top tension of circular cylinder on the amplitude ratio, frequency ratio and added mass coefficient was evaluated. The results showed that top tension had a greater influence on the amplitude; the added mass coefficient demonstrated a nonlinear relationship with external flow velocity. The added mass coefficient decreases when the reduced velocity increases. At a particular reduced velocity, the added mass coefficient decreases when the top tension increases or mass ratio increases.