Talks and Poster Presentations (with Proceedings-Entry):
B. Scheichl, A. Kluwick:
"Level of Turbulence Intensity Associated with Bluff-Body Separation for Large Values of the Reynolds Number";
Talk: 5th AIAA Theoretical Fluid Mechanics Conference,
Doubletree Hotel Seattle Airport, Seattle, WA, USA;
2008-06-23
- 2008-06-26; in: "2008 AIAA Meeting Papers on Disc",
American Institute of Aeronautics and Astronautics (AIAA),
7, TFM-8: Turbulent Boundary Layers II
(2008),
ISBN: 978-1-60086-995-2;
Paper ID AIAA 2008-4348,
23 pages.
English abstract:
The paper deals with a rational and physically feasible description of gross separation from the surface of a plane and more-or-less bluff obstacle in an incompressible and otherwise perfectly uniform stream for arbitrarily large values of the globally formed Reynolds number. The analysis is initialized by a remarkable conclusion drawn from recent theoretical results that is corroborated by experimental findings but apparently contrasts common reasoning: the attached boundary layer extending from the front stagnation point to the position of separation at the body surface never attains a fully developed turbulent state, even in the limit of infinite Reynolds number. As a consequence, the boundary layer exhibits a certain level of turbulence intensity that is determined by the separation process governed by locally strong viscous/inviscid flow interaction. This mechanism is expected to be associated with rapid transition of the separating shear layer towards a fully developed turbulent state. Here a rigorous asymptotic analysis, essentially carried out without resorting to a specific turbulent closure and supported by a numerical investigation, of the topology of the boundary layer flow close to separation is presented.
Keywords:
bluff-body separation, boundary layers, Kirchhoff flow, matched asymptotic expansions, turbulence intensity
"Official" electronic version of the publication (accessed through its Digital Object Identifier - DOI)
http://dx.doi.org/10.2514/6.2008-4348
Electronic version of the publication:
http://publik.tuwien.ac.at/files/PubDat_164946.pdf
Created from the Publication Database of the Vienna University of Technology.