Global effect of local skin friction drag reduction in spatially developing turbulent boundary layer
Stroh A, Hasegawa Y, Schlatter P, Frohnapfel B (2016)
Publication Type: Journal article
Publication year: 2016
Journal
Book Volume: 805
Pages Range: 303-321
DOI: 10.1017/jfm.2016.545
Abstract
A numerical investigation of two locally applied drag-reducing control schemes is carried out in the configuration of a spatially developing turbulent boundary layer (TBL). One control is designed to damp near-wall turbulence and the other induces constant mass flux in the wall-normal direction. Both control schemes yield similar local drag reduction rates within the control region. However, the flow development downstream of the control significantly differs: persistent drag reduction is found for the uniform blowing case, whereas drag increase is found for the turbulence damping case. In order to account for this difference, the formulation of a global drag reduction rate is suggested. It represents the reduction of the streamwise force exerted by the fluid on a plate of finite length. Furthermore, it is shown that the far-downstream development of the TBL after the control region can be described by a single quantity, namely a streamwise shift of the uncontrolled boundary layer, i.e. a changed virtual origin. Based on this result, a simple model is developed that allows the local drag reduction rate to be related to the global one without the need to conduct expensive simulations or measurements far downstream of the control region.
Authors with CRIS profile
Involved external institutions
Karlsruhe Institute of Technology (KIT)
Germany (DE)
University of Tokyo
Japan (JP)
Royal Institute of Technology / Kungliga Tekniska Högskolan (KTH)
Sweden (SE)
Germany (DE)
University of Tokyo
Japan (JP)
Royal Institute of Technology / Kungliga Tekniska Högskolan (KTH)
Sweden (SE)
How to cite
APA:
Stroh, A., Hasegawa, Y., Schlatter, P., & Frohnapfel, B. (2016). Global effect of local skin friction drag reduction in spatially developing turbulent boundary layer. Journal of Fluid Mechanics, 805, 303-321. https://doi.org/10.1017/jfm.2016.545
MLA:
Stroh, Alexander, et al. "Global effect of local skin friction drag reduction in spatially developing turbulent boundary layer." Journal of Fluid Mechanics 805 (2016): 303-321.
BibTeX: Download