Calculation of Vortex Shedding From a Circular Cylinder in Uniform and Shear Flows

The present paper deals with numerical investigations of vortex shedding from a circular cylinder in uniform and shear flows. The computational approach is based on solving the complete Transient Reynolds-Averaged Navier-Stokes (TRANS) equations. The ζ-f model proposed recently by Hanjalic et al. (2004) is used for comparison with the recent computations of Basara et al. (2003) who used the Reynolds-stress model (RSM) developed by Speziale et al. (1991) and the hybrid EVM/RSM turbulence model developed by Basara and Jakirlic (2003). The recent study of the same flows (Basara, Jakirlic and Alajbegovic (2003)) showed that the wall treatment has an important role in correct predictions of forces acting on a cylinder. In this work, a new compound wall treatment (CWT) of Popovac and Hanjalic (2005) was used. A simple modification to the treatment of the dissipation rate of the original CWT is proposed. Furthermore, a new ν_t - k - ζ - f model is modeled on the basis of an exact form derived from the ζ-f model and the first results are given here. Calculations with the ζ-f model employed as a low-Re number model are performed and the results are compared with those obtained with the same model in conjunction with CWT.