大ブロッケージ係数の場合のキャビテーション試験水槽測定部内の遷移レイノルズ数の特異な挙動
2003 年 31 巻 2 号 p. 91-96
詳細
2003 年 31 巻 2 号 p. 91-96
In order to clarify the wall effects upon Recso often observed in valve experiments, we take up a simple flow around a circular cylinder of diameter d set within a two-dimensional channel of hight h, when the blockage factor B=d/h=0.75. And systematical measurements are made for the upstream-and the downstream-velocity distribution around the cylinder, by means of an PIV-technique, resulting in time-averaged nondimensional velocity change Δu/u1, in proportion to the drag coefficient with respect to Reynolds number Re. In the present case of extremely high B-Rec is unexpectedly reduced about one figure than the small B-counterparts.
