Turbulent wake of a finite circular cylinder of small aspect ratio

Abstract

The turbulent wake of a finite circular cylinder mounted normal to a wall and partially immersed in a turbulent boundary layer was studied experimentally using two-component thermal anemometry in a low-speed wind tunnel. Four circular cylinders of aspect ratios AR=9, 7, 5, and 3 were tested at a Reynolds number of ReD = 6 × 1 04. The cylinders were either completely or partially immersed in the wall boundary layer, where the boundary layer thickness relative to the cylinder diameter was δ / D = 3.0. A similar turbulent wake structure (mean velocity, turbulence intensity, and Reynolds shear stress distributions) was found for cylinders of AR=9, 7, and 5, while a distinctly different turbulent wake structure was found for the cylinder of AR=3. This was consistent with the results of a previous study that focused on the time-averaged streamwise vortex structures in the wake. © 2006 Elsevier Ltd. All rights reserved.