Numerical analysis of freestream turbulence effects on the vortex-induced vibrations of a rectangular cylinder

Large-Eddy Simulation of the flow around an elastically mounted rectangular cylinder with an aspect ratio 4 was undertaken. 1DOF analysis of the heaving and torsional motions was performed under a free vibration. Various characteristics of the flow-field at lock-in are discussed. Subsequently, a divergence-free synthetic inflow generation approach was employed to analyse the effects of the freestream turbulence on the bridge response. The inflow turbulence intensity and integral length scales were systematically studied. The effect of turbulence intensity (up to 12%) was shown to deplete the structural response for both torsional and heaving motions. A variation of the tested integral length scales, which were order of the cylinder dimensions, had less effects (than a variation of the turbulence intensity) on the structure response.