カメタニ　ユキノリ   KAMETANI YUKINORI   亀谷　幸憲    所属   明治大学  理工学部    職種   専任講師
言語種別	英語
発行・発表の年月	2011/08
形態種別	学術雑誌
査読	査読あり
標題	Direct numerical simulation of spatially developing turbulent boundary layers with uniform blowing or suction
執筆形態	共著(筆頭者)
掲載誌名	Journal of Fluid Mechanics
掲載区分	国外
出版社・発行元	CAMBRIDGE UNIV PRESS
巻・号・頁	681,pp.154-172
著者・共著者	◎Yukinori Kametani, Koji Fukagata
概要	Direct numerical simulation (DNS) of spatially developing turbulent boundary layer with uniform blowing (UB) or uniform suction (US) is performed aiming at skin friction drag reduction. The Reynolds number based on the free stream velocity and the 99% boundary layer thickness at the inlet is set to be 3000. A constant wall-normal velocity is applied on the wall in the range,-'0.01U∞ ≤ Vctr ≤ 0.01U ∞. The DNS results show that UB reduces the skin friction drag, while US increases it. The turbulent fluctuations exhibit the opposite trend. Dynamical decomposition of the local skin friction coefficient using the identity equation (FIK identity, Fukagata et al., 2002) reveals that the mean convection term in UB case works as a strong drag reduction factor, while that in US case works as a strong drag augmentation factor. It is also found that the control efficiency of UB is much higher than that of the advanced active control methods proposed for channel flows.
DOI	10.1017/jfm.2011.219
ISSN	0022-1120