Investigation of flow interference between two inline square cylinders with different spacing ratios in subcritical Reynolds number regime

Abstract

When two cylinders are in proximity with each other the vortex shedding of one cylinder are influenced by the other. The flow field becomes even more complex when one cylinder subjected to an oscillation. In present study flow around two inline square cylinders of aspect ratio 50 at different spacing ratio is investigated experimentally. Experiments are performed for two identical square cylinders of 6 mm diameter at Reynolds number 500 in a low speed wind tunnel using Particle image velocimetry (PIV) and hotwire anemometer (HWA). The upstream cylinder is given predetermined oscillation and the gap between the two cylinders varied over wide range. Present study focused on effect of forcing frequency and spacing between centers of two cylinders (s/D = 1.5–5.0). The upstream cylinder is oscillated in transverse direction at f/f0 = 0 to 2 and the effect of this oscillation is observed behind the downstream stationary cylinder at different spacing of the cylinders by hotwire.