The authors report the results of vortex-induced vibrations of a square cylinder in a wind tunnel. This constitutes a high mass ratio environment. The square cylinder is mounted in the wind tunnel in such a fashion that it only performs rigid body oscillations perpendicular to the flow direction with damped free-end conditions. This physical situation allows a direct evaluation for analytical models relying on simplified 2D assumptions. The results are also compared with two-dimensional fluid-structure (CFD-CSD) numerical simulations. The comparison shows that despite having one-dimensional motion, the analytical model does not predict the VIV region with correctness. Results show that the numerical simulations and experimental results differ from the analytical model for the prediction of reduced velocity corresponding to peak amplitude. Also the analytical reduced velocity envelope is underpredicted compared to both numerical simulations and experimental data despite the structure being lightly damped. The findings are significant as the experimental results for freely oscillating high mass ratio body show differences from the low mass ratio especially in the transition between VIV and galloping regions. However the numerical simulations show comparatively close agreement.

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A 2D multi-block high-speed compressible turbulent flow solver CFD2D based on the Jones and Launders two-equation k-ε turbulence model is developed. Method of solution employed is Finite Volume Method. Its basic algorithm is based on the approximate Riemann solver with the three-step Runge-Kutta time integration. Its additional feature includes Wilcox model for compressibility correction of k-ε turbulence model, Girmaji algebraic Reynolds stress (non-linear stress) model and linear stress model for evaluation of turbulent stresses. For validation purpose, code is applied to a 2D diamond aerofoil and a wedge ramp attached to a flat plate. CFD-predicted results are compared to the experimental results for shock wave and shock wave boundary layer interaction on the trailing edge of the fin. Contour plots are also compared to the Schlieren photographs. Flow simulation shows ability of the code to capture the physics of the flow both qualitatively and quantitatively.

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