RANS Predictions of Turbulent Flow Past a Circular Cylinder over the Critical Regime
نویسنده
چکیده
Incompressible, turbulent flow past a circular cylinder is computationally investigated by means of Reynolds Averaged Numerical Simulations. Problems in using the wall-functions approach for modeling the near-wall turbulence are demonstrated. As the main turbulence model, the Shear Stress Transport model is employed, by resolving the nearwall layer. A wide range of Reynolds numbers is investigated (Re=110 to 510), encompassing the critical regime. Predicted drag coefficients are compared with measurements from the literature. The procedure is shown to be able to predict the boundary layer transition and the associated drag coefficient reduction, qualitatively. Quantitatively, predicted drag coefficients are observed to underestimate measurements for all Reynolds numbers. Present analysis will be extended to more sophisticated transient models, which will be discussed in the oral presentation. Key-Words: Turbulent Flow Past Circular Cylinder, RANS, SST model, CFD.
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