Flow above the free end of a surface-mounted finite-height cylinder

Abstract

The flow above the free end of a surface-mounted finite-height circular cylinder was studied experimentally in a low-speed wind tunnel using particle image velocimetry. Velocity measurements were taken in horizontal and vertical planes above the free end at a Reynolds number of Re = 4.2 × 104. Four cylinder aspect ratios, of AR = 9, 7, 5, and 3, were examined. The turbulent boundary layer on the ground plane had a thickness of δ/D = 1.6. The results revealed details of the mean recirculation zone, reattachment position, critical points, and vortex patterns in the flow field above the free end. The sensitivity of the free-end flow field to changes in AR was much less pronounced than what is observed for the near-wake region.