The interaction of a laminar boundary layer with a cylinder, known as junction flow, is well investigated previously both computationally and experimentally. Due to the adverse pressure gradient opposed by the obstacle and the attendant wall flux of vorticity, the boundary layer separates upstream of the obstacle, resulting in the emergence and development of Reynoldsnumber dependent system of necklace vortices. This research experimentally investigates a similar scenario involving the interaction between a shear-wake and a circular cylinder. The experiments utilize hydrogen bubble flow visualizations in a water channel capable of generating laminar shear wake from two streams of independently controlled flows. A cylinder is positioned within the shear wake such that its axis is perpendicular to both the main flow direction and the incoming vorticity. For a fixed cylinder diameter and shear wake width, the two key non-dimensional parameters are the Reynolds number (Re) and shear ratio (SR) of the shear-wake. Investigation of these two parameters reveals a vortex mapping regime that is fundamentally different from those observed in junction flows. This presentation primarily focuses on the various regimes observed under such flow conditions. Furthermore, owing to the absence of a bounding wall, this flow entails clarification regarding the mechanisms underlying the formation of the necklace vortex systems away from the wall. These mechanisms are fundamentally different from the flow separation and vortex formation observed in boundary layer junction flow in that there is no opposing sign flux of vorticity introduced from a physical wall owing to a pressure gradient.
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