三角形溝つき円柱周りの流れ
2004 年 70 巻 694 号 p. 1467-1472
詳細
2004 年 70 巻 694 号 p. 1467-1472
In the flow around a circular cylinder, the sudden decrease in the drag force occurs at a high Reynolds number, but the same phenomenon occurs at a lower Reynolds number in the case where there exist grooves or roughness on the circular cylinder surface. In this paper, in order to make clear the flow characteristics around a circular cylinder with triangular grooves, drag coefficient, pressure distribution and Strouhal number were measured. Moreover the flow was analyzed by applying the RNG k-ε turbulent model and the surface flow pattern was investigated using oil-film technique. Consequently, it is made clear that the reattachment point changes position in each groove and the drag coefficient of a circular cylinder with triangular grooves decreases compared with a circular cylinder with arc grooves.
