COHERENT STRUCTURE AND CHARACTERISTIC VELOCITY DISTRIBUTION OF THE FLOW FIELD NEAR THE RECTANGULAR CYLINDER

Abstract

Coherent structure and the properties of the velocity fluctuation of the flow field near the rectangular cylinder are investigated using the flow visualization techniques and PTV. In flow visualization, halogen light sheets were used in side view, plan view and streamwise view. Separation vortex are formed in shear layer on the top and side surface of rectangular cylinder. And horseshoe vortex are existed at the bottom wall outside of cylinder. The specific velocity distribution and velocity fluctuation property are shown as characteristic phenomenon by the different position. It should be noted that the relationship of coherent structure and the properties of the velocity fluctuation are cleared.