436 溝付円柱の表面構造変化による流動特性(G05-9 複雑流れ(2),G05 流体工学)  [in Japanese] 436 Flow Characteristics by the change of surface structure of the Circular Cylinder with the Grooves  [in Japanese]

This paper describes an experimental study on the flow patterns and the characteristic of flow around a circular cylinder with grooves. The surface pressure when changing Reynolds number (Re=0.4×10^5〜4.2×10^5) measured with the cylinder with grooves of three kinds of grooves number (32, 48, 64) Drag coefficient is calculated from the pressure distribution and the flow around the cylinder with grooves is investigated by hot wire and visualization. From the results, It is clarified that minimum drag coefficient shifts to high Reynolds number side as groove number increases. It turns out that wake area, separation point change and the drag coefficient is affected with the number of grooves