Numerical simulation of multi-modal vortex-induced vibration of a 3D flexible circular cylinder

Vortex-induced vibration of a 3D flexible circular cylinder at a constant Reynolds number Re = 1000 is numerically investigated using a fully coupled Computational Fluid Dynamics (CFD) and Computational Structural Dynamics (CSD) method. The dynamic response of a flexible cylinder with fixed ends is modelled by the Euler-Bernoulli beam theory. Simulation results show that by increasing the reduced velocity, different vibration modes (up to the 5th mode) are excited. The flow visualization results suggest that 2S wake mode is observed at all span-wise planes. Depending on the vibration amplitude, the vortex shedding mode can be either AS mode or SS mode.