1601 隅切り角柱周りの流動特性(G05-1 流体工学(1)物体・生体まわりの流れ,21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

Abstract

It is known that in a square cylinder with uniform flow, the drag force changes with angle of attack. To clarify the flow characteristics around a square cylinder with corner cutoffs we analyzed the drag coefficient, and the Strouhal number were measured. Moreover, the flow around the square cylinder with corner cutoffs was analyzed by applying the RNG k-ε turbulent model, and the surface flow pattern was investigated using visualization by the oil-film method and mist flow. From these results, the sudden decrease of drag coefficient occurs at an angle of attack about α=0〜10℃ in the case of the square cylinder with corner cutoffs compared with the square cylinder. The minimum value of drag coefficient for the square cylinder with corner cutoffs decreases about 30%, since the wake area of the square cylinder with corner cutoffs becomes smaller compared with that of the square cylinder.