COMPARISON OF RELEVANT PARAMETERS OF THE EXTERNAL FLOW OF A SQUARE CYLINDER BY TWO DIFFERENT TURBULENCE MODELS

RSM AND SST-Kω

Abstract

Rectangular cylinders are recurrent in engineering, a particular case is a square. Structures with square shapes are of great interest and their real applications can be seen in columns, towers, counterwind structures of tall buildings, etc. The present work analyses, in bidimensional domain, the external incompressible flow over a cylinder by turbulence models SST-kω and RSM through ANSYS Fluent. In the studied cases the objective is to analyze comparatively relevant parameters of the flow: drag coefficient and Strouhal number. The average pressure coefficient over the cylinder is also evaluated. In all cases analyzed the flow parameters converged to the experimental data. The average pressure coefficient over the cylinder did not present good correlation with the experiments for both turbulence models. The main differences are in the cylinder faces parallel to the flow. The analysis shows that RSM model was able to reproduce accurately the flow parameters with better agreement in drag coefficient. However, this model has a greater computational cost since it adds more equations to be solved and has performed worse than SST-kω model.