The Vortex-induced vibration on a circular cylinder is investigated by the numerical solution of the unsteady Navier-Stokes equations and results are compared with experimental measurements obtained by different authors. The Beam and Warming implicit factored scheme is used to solve the governing equations and Large Eddy Simulation is used together with the Smagorinsky subgrid-scale model (SGS) to simulate the turbulent flow in the wake of the cylinder. The cylinder is laterally supported by a spring and a damper and is free to oscillate in the transversal direction in an initially uniform flow for the first flow speed investigated. For the subsequent speeds, the final condition obtained for the previous speed is used as initial condition to reproduce the actual experimental set up. In that case, the measurements are done by progressive increments of the flow speed retaining the fluid memory effect. The complexity and high sensitivity of the flow phenomenon at this configuration requires a very accurate and robust numerical model. Most of the known algorithms failed to duplicate the available experimental measurements. The proposed numerical solution was able to provide a good picture of the real physics of the phenomenon showing the Karman vortex street effects on the lift and drag coefficients. The numerical results for the transversal oscillation amplitude are compared to experimental data showing a fairly precise agreement at the difficult to simulate regime of the lock-in phenomenon.
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