Resonance experiments of vortex-induced vibrations based on frequency lock

When the fluid flows around the bluffy body, the vortex will be formed and shed alternatively behind the bluff body in the near wake. As the frequency of vortex shedding is close or equal to the natural frequency of structure, the resonance vibration will occur, even endangers the safety of structure. Due to the difficulty in detection of natural frequency of structure, experiments of vortex-induced vibrations (VIV) are carried out difficultly. In present paper, the structure is designed as a cylindrical pendulum. By using the method of frequency lock (FL), which indicates the vortex shedding frequency locked to the natural frequency of cylindrical pendulum, the VIV experiments are then designed.