Effect of harmonic inflow perturbation on the wake vortex dynamics of a cylinder undergoing two-degree-of-freedom vortex-induced vibration near a plane boundary

The influence of inflow perturbations on the wake dynamics and structural response is investigated for a cylinder undergoing vortex-induced vibrations (VIV) in oscillatory flows in the proximity of a solid boundary. Numerical simulations are conducted at a Reynolds number of 200, based on the cylinder diameter and free-stream velocity, for perturbation frequencies fp up to four times the natural shedding frequency fo. Three response regimes are identified: a lock-on regime at fp=2fo, with maximum cylinder displacement and forces, a force-amplification regime for 1.8