Suppression Of Vortex Street Downstream Of An Oscillating Cylinder By A Splitter Plate

Abstract: The suppression of vortex shedding from oscillating circle cylinders wasstudied experimentally. A splitter plate was used and set along the centerline of thewake to suppress vortex shedding from a stream-wisely oscillating cylinder ofdiameter D at Reynolds numbers Re=V D/=1.01×104,1.35×104and1.69×104, feD/V was from0to0.1, and A/D=0.2, where A was the amplitude of the oscillatingcircle cylinder. The control parameters were L/D and G/D, where L was the length ofplate and G was the distance between central position of cylinder oscillation andleading edge of plate. The stream-wise dimension L was parallel to the comingstream. PIV, smoke-wire flow visualization, hot-wire measurement of fluctuatingvelocities at different points in the cylinder wake, and electronic scanning valvemeasurement of instantaneous pressure distribution on surface of the oscillatingcircle cylinder were carried out in a wind tunnel.Comparing with a splitter plate, flow of the wake of the oscillating cylinder wasobserved without it through PIV experiment. The experiment showed that vortexshedding from oscillating circle cylinders was suppressed by a splitter plate. Theresults, which were from two experiments of hot-wire measurement and electronicscanning valve measurement, showed that vortex shedding from both sides of thecylinder could be suppressed and mean drag and fluctuating lift of the cylinder couldbe reduced, if the splitter plate was applied in a certain region called effective zone.The effective zone was increasing with the increase in the length of splitter plate. Theeffective zone was decreasing with the increase in the Reynolds numbers. It alsodistinctly presented flow visualization by smoke-wire flow visualization.The experiments further showed that vortex shedding from the oscillating circlecylinder could be controlled by splitter plate.