Comparative Analysis of 2D and 3D Simulations of Vortex-Induced Vibrations at Supercritical Reynolds Regime using OpenFOAM*

The analysis of Vortex-Induced Vibrations (VIV) at high Reynolds numbers presents significant challenges due to the complex fluid-structure interactions and the limited availability of comprehensive data in experimental data and numerical simulation investigations in the existing literature. As the offshore industry seeks to minimize the impact of VIV on structural components such as platform legs and riser fairings, which are typically cylindrical in shape. In this study, we employed a numerical investigation to analyze the flow field and its forces for a specified range of reduced velocities of 3, 7, 8 and 10 using Computational Fluid Dynamics (CFD) simulations through the Finite Volume Method (FVM) implemented in the OpenFOAM software. Vortex-induced vibrations are analyzed for two different spatial discretization strategies, 2D and 3D investigations were conducted for circular cylinder free to vibrate in the cross-flow direction. In both cases, the characteristic mass-damping parameter used was m^* ζ=0.00858, and the flow regime is given by Re=1×10^6. We employed for the 2D analyses the Unsteady Reynolds Averaged Navier-Stokes (URANS) equation, and (DES) for 3D cases, both turbulence models were employed along with Menter's k−ω SST model as a turbulence closure model, to perform the numerical investigations. The loads on the cylinder are analyzed in terms of nondimensional displacement and time histories of the lift and drag coefficients for each reduced velocity. The key findings in the simulation results include maximum vibration amplitude at reduced velocities 7 and 8, representing an extension of the upper branch for higher reduced velocities, which is expected according to the literature for the supercritical Reynolds regime.