End effects of circular cylinder on its wake at Reynolds number of O(104)

Abstract

With the Transverse Control Cylinder Technique (TCCT), the effects of the end-conditions of a circular cylinder to its wake at high Reynolds numbers ( ) were studied. Experimental results showed that before the inclusion of the control cylinders, the vortex shedding pattern was curved due to the influences of the cylinder end conditions and test section wall boundary layers. The control cylinders sped up the flow velocity near the ends of the test cylinder, and changed the spanwise pressure distribution over the test cylinder. By locating the control cylinders at various distances from the test cylinder, different vortex shedding patterns, including parallel, oblique and curved shedding were successfully induced. Various aerodynamic parameters including the pressure coefficients, drag and lift coefficient, Strouhal number were also measured and presented.