Numerical study on the suppression of the vortex-induced vibration of an elastically mounted cylinder by a traveling wave wall

• Suppression of the VIV of a circular cylinder by a traveling wave wall (TWW) is studied by using CFD simulations.
• Control effects of TWW at different startup moments are investigated.
• Stable small-scale vortices are formed in the troughs of the TWW.
• TWW can significantly suppress the cross-flow and inline flow vibrations of the cylinder.
• TWW can remarkably decrease the fluctuation of the lift force and the mean value of the drag force.

In the present paper, the commercial CFD code “Fluent” was employed to perform 2-D simulations of an entire process that included the flow around a fixed circular cylinder, the oscillating cylinder (vortex-induced vibration, VIV) and the oscillating cylinder subjected to shape control by a traveling wave wall (TWW) method. The study mainly focused on using the TWW control method to suppress the VIV of an elastically supported circular cylinder with two degrees of freedom at a low Reynolds number of 200. The cross flow (CF) and the inline flow (IL) displacements, the centroid motion trajectories and the lift and drag forces of the cylinder that changed with the frequency ratios were analyzed in detail. The results indicate that a series of small-scale vortices will be formed in the troughs of the traveling wave located on the rear part of the circular cylinder; these vortices can effectively control the flow separation from the cylinder surface, eliminate the oscillating wake and suppress the VIV of the cylinder. A TWW starting at the initial time or at some time halfway through the time interval can significantly suppress the CF and IL vibrations of the cylinder and can remarkably decrease the fluctuations of the lift coefficients and the average values of the drag coefficients; however, it will simultaneously dramatically increase the fluctuations of the drag coefficients.