Contributions of the wall boundary layer to the formation of the counter-rotating vortex pair in transverse jets

Handle URI:
http://hdl.handle.net/10754/597853
Title:
Contributions of the wall boundary layer to the formation of the counter-rotating vortex pair in transverse jets
Authors:
SCHLEGEL, FABRICE; WEE, DAEHYUN; MARZOUK, YOUSSEF M.; GHONIEM, AHMED F.
Abstract:
Using high-resolution 3-D vortex simulations, this study seeks a mechanistic understanding of vorticity dynamics in transverse jets at a finite Reynolds number. A full no-slip boundary condition, rigorously formulated in terms of vorticity generation along the channel wall, captures unsteady interactions between the wall boundary layer and the jet - in particular, the separation of the wall boundary layer and its transport into the interior. For comparison, we also implement a reduced boundary condition that suppresses the separation of the wall boundary layer away from the jet nozzle. By contrasting results obtained with these two boundary conditions, we characterize near-field vortical structures formed as the wall boundary layer separates on the backside of the jet. Using various Eulerian and Lagrangian diagnostics, it is demonstrated that several near-wall vortical structures are formed as the wall boundary layer separates. The counter-rotating vortex pair, manifested by the presence of vortices aligned with the jet trajectory, is initiated closer to the jet exit. Moreover tornado-like wall-normal vortices originate from the separation of spanwise vorticity in the wall boundary layer at the side of the jet and from the entrainment of streamwise wall vortices in the recirculation zone on the lee side. These tornado-like vortices are absent in the case where separation is suppressed. Tornado-like vortices merge with counter-rotating vorticity originating in the jet shear layer, significantly increasing wall-normal circulation and causing deeper jet penetration into the crossflow stream. © 2011 Cambridge University Press.
Citation:
SCHLEGEL F, WEE D, MARZOUK YM, GHONIEM AF (2011) Contributions of the wall boundary layer to the formation of the counter-rotating vortex pair in transverse jets. Journal of Fluid Mechanics 676: 461–490. Available: http://dx.doi.org/10.1017/jfm.2011.59.
Publisher:
Cambridge University Press (CUP)
Journal:
Journal of Fluid Mechanics
Issue Date:
8-Apr-2011
DOI:
10.1017/jfm.2011.59
Type:
Article
ISSN:
0022-1120; 1469-7645
Sponsors:
The research was supported by the Mathematical, Information, and Computational Sciences (MICS) program of the Office of Science in the US Department of Energy under the grant number DE-FG02-98ER25355, as well as King Abdullah University of Science and Technology (KAUST). Computational support for large-scale scientific simulations was provided by both the National Energy Research Scientific Computing Center (NERSC) and KAUST. The third author also acknowledges support from the US Department of Energy (DOE), Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, during his stay at Sandia National Laboratories. Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US DOE under contract DE-AC04-94-AL85000.
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Full metadata record

DC FieldValue Language
dc.contributor.authorSCHLEGEL, FABRICEen
dc.contributor.authorWEE, DAEHYUNen
dc.contributor.authorMARZOUK, YOUSSEF M.en
dc.contributor.authorGHONIEM, AHMED F.en
dc.date.accessioned2016-02-25T12:57:49Zen
dc.date.available2016-02-25T12:57:49Zen
dc.date.issued2011-04-08en
dc.identifier.citationSCHLEGEL F, WEE D, MARZOUK YM, GHONIEM AF (2011) Contributions of the wall boundary layer to the formation of the counter-rotating vortex pair in transverse jets. Journal of Fluid Mechanics 676: 461–490. Available: http://dx.doi.org/10.1017/jfm.2011.59.en
dc.identifier.issn0022-1120en
dc.identifier.issn1469-7645en
dc.identifier.doi10.1017/jfm.2011.59en
dc.identifier.urihttp://hdl.handle.net/10754/597853en
dc.description.abstractUsing high-resolution 3-D vortex simulations, this study seeks a mechanistic understanding of vorticity dynamics in transverse jets at a finite Reynolds number. A full no-slip boundary condition, rigorously formulated in terms of vorticity generation along the channel wall, captures unsteady interactions between the wall boundary layer and the jet - in particular, the separation of the wall boundary layer and its transport into the interior. For comparison, we also implement a reduced boundary condition that suppresses the separation of the wall boundary layer away from the jet nozzle. By contrasting results obtained with these two boundary conditions, we characterize near-field vortical structures formed as the wall boundary layer separates on the backside of the jet. Using various Eulerian and Lagrangian diagnostics, it is demonstrated that several near-wall vortical structures are formed as the wall boundary layer separates. The counter-rotating vortex pair, manifested by the presence of vortices aligned with the jet trajectory, is initiated closer to the jet exit. Moreover tornado-like wall-normal vortices originate from the separation of spanwise vorticity in the wall boundary layer at the side of the jet and from the entrainment of streamwise wall vortices in the recirculation zone on the lee side. These tornado-like vortices are absent in the case where separation is suppressed. Tornado-like vortices merge with counter-rotating vorticity originating in the jet shear layer, significantly increasing wall-normal circulation and causing deeper jet penetration into the crossflow stream. © 2011 Cambridge University Press.en
dc.description.sponsorshipThe research was supported by the Mathematical, Information, and Computational Sciences (MICS) program of the Office of Science in the US Department of Energy under the grant number DE-FG02-98ER25355, as well as King Abdullah University of Science and Technology (KAUST). Computational support for large-scale scientific simulations was provided by both the National Energy Research Scientific Computing Center (NERSC) and KAUST. The third author also acknowledges support from the US Department of Energy (DOE), Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences, during his stay at Sandia National Laboratories. Sandia National Laboratories is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the US DOE under contract DE-AC04-94-AL85000.en
dc.publisherCambridge University Press (CUP)en
dc.subjectjetsen
dc.subjectvortex flowsen
dc.titleContributions of the wall boundary layer to the formation of the counter-rotating vortex pair in transverse jetsen
dc.typeArticleen
dc.identifier.journalJournal of Fluid Mechanicsen
dc.contributor.institutionMassachusetts Institute of Technology, Cambridge, United Statesen
dc.contributor.institutionEwha Womans University, Seoul, South Koreaen
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