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KAMETANI YUKINORI
Department Undergraduate School , School of Science and Technology Position Senior Assistant Professor |
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| Language | English |
| Publication Date | 2012 |
| Type | Academic Journal |
| Peer Review | Peer reviewed |
| Invitation | Invited paper |
| Title | Direct numerical simulation of spatially developing turbulent boundary layer for skin friction drag reduction by wall surface-heating or cooling |
| Contribution Type | Co-authored (first author) |
| Journal | Journal of Turbulence |
| Journal Type | Another Country |
| Publisher | Taylor & Francis LTD |
| Author and coauthor | ◎Yukinori Kametani, Koji Fukagata |
| Details | Direct numerical simulation (DNS) of zero-pressure-gradient spatially developing tur- bulent boundary layer with uniform heating (UH) or cooling (UC) is performed aiming at skin friction drag reduction. A constant temperature is imposed on the wall. The DNS results show that UC reduces skin friction drag with a maximum drag reduction rate of 65%, while UH enhances it. Dynamical decomposition of skin friction drag using the identity equation (FIK identity, discussed by Fukagata et al. in 2002) quantitatively shows that drag reduction by UC is due to reduced Reynolds shear stress (RSS), while drag increase by UH is augmentation of RSS. The control efficiency of UC, however, is found to be largely negative; namely, net power saving is not achieved. |