The influence of stable stratification on the transition to turbulence in a temporal mixing layer
Autor(a) principal: | |
---|---|
Data de Publicação: | 2006 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Institucional da FURG (RI FURG) |
Texto Completo: | http://repositorio.furg.br/handle/1/1069 |
Resumo: | The transition to turbulence in a stably stratified flow is a problem of considerable interest in fluid dynamics with applications in both geophysical sciences and engineering. This transition is controlled by competition between the vertical shear of the base flow and the buoyancy forces due to the density stratification. The present work investigates numerically the effect of stable stratification on the development of a Kelvin-Helmholtz (KH) instability and the formation of streamwise vortices, which are developed after the saturation of the primary billows of KH. The Direct Numerical Simulation (DNS) technique was used to solve the complete Navier-Stokes equations, in the Boussinesq approximation. Numerical tests were done with different Richardson numbers and forced initial conditions for velocity fluctuations. The results showed that high stratification inhibits the pairing process, reduces the buoyancy flux, weakens the vertical motions, decreases the thickness of the mixing layer and affects the formation of streamwise vortices. The three-dimensional results demonstrated that the streamwise vortices are clearly formed in non-stratified cases. In the stratified cases, on the other hand, the streamwise vortices are weakened, due to the streamwise density gradient, which decrease the levels of vorticity in the billows of KH, while increase in the braid zone. |
id |
FURG_c0ace99fb559ae29593a88367189bbf4 |
---|---|
oai_identifier_str |
oai:repositorio.furg.br:1/1069 |
network_acronym_str |
FURG |
network_name_str |
Repositório Institucional da FURG (RI FURG) |
repository_id_str |
|
spelling |
Martinez, Denise Maria VarellaSchettini, Edith Beatriz CamañoSilvestrini, Jorge Hugo2011-10-01T04:19:29Z2011-10-01T04:19:29Z2006MARTINEZ, D. M. V..; SCHETTINI, E.B. C.; SILVESTRINI, J. H.. The influence of stable stratification on the transition to turbulence in a temporal mixing layer. J. Braz. Soc. Mech. Sci. & Eng. 2006, vol. 28, n. 2, p. 242-252. Disponível em: <http://www.scielo.br/pdf/jbsmse/v28n2/29757.pdf> Acesso em: 30 set. 2011.1678-5878http://repositorio.furg.br/handle/1/106910.1590/S1678-58782006000200014The transition to turbulence in a stably stratified flow is a problem of considerable interest in fluid dynamics with applications in both geophysical sciences and engineering. This transition is controlled by competition between the vertical shear of the base flow and the buoyancy forces due to the density stratification. The present work investigates numerically the effect of stable stratification on the development of a Kelvin-Helmholtz (KH) instability and the formation of streamwise vortices, which are developed after the saturation of the primary billows of KH. The Direct Numerical Simulation (DNS) technique was used to solve the complete Navier-Stokes equations, in the Boussinesq approximation. Numerical tests were done with different Richardson numbers and forced initial conditions for velocity fluctuations. The results showed that high stratification inhibits the pairing process, reduces the buoyancy flux, weakens the vertical motions, decreases the thickness of the mixing layer and affects the formation of streamwise vortices. The three-dimensional results demonstrated that the streamwise vortices are clearly formed in non-stratified cases. In the stratified cases, on the other hand, the streamwise vortices are weakened, due to the streamwise density gradient, which decrease the levels of vorticity in the billows of KH, while increase in the braid zone.engStable stratificationDirect numerical simulationMixing layerBuoyancy force,Transition to turbulenceThe influence of stable stratification on the transition to turbulence in a temporal mixing layerinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccessreponame:Repositório Institucional da FURG (RI FURG)instname:Universidade Federal do Rio Grande (FURG)instacron:FURGORIGINALThe influence of stable stratification on the transition to turbulence in a temporal mixing layer.pdfThe influence of stable stratification on the transition to turbulence in a temporal mixing layer.pdfapplication/pdf489101https://repositorio.furg.br/bitstream/1/1069/1/The%20influence%20of%20stable%20stratification%20on%20the%20transition%20to%20turbulence%20in%20a%20temporal%20mixing%20layer.pdf8a53bf83a118ff09431f1433438ef685MD51open accessLICENSElicense.txtlicense.txttext/plain; charset=utf-81724https://repositorio.furg.br/bitstream/1/1069/2/license.txt5b92b9704b4f13242d70e45ddef35a68MD52open access1/10692022-10-21 15:16:38.73open accessoai:repositorio.furg.br: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Repositório InstitucionalPUBhttps://repositorio.furg.br/oai/request || http://200.19.254.174/oai/requestopendoar:2022-10-21T18:16:38Repositório Institucional da FURG (RI FURG) - Universidade Federal do Rio Grande (FURG)false |
dc.title.pt_BR.fl_str_mv |
The influence of stable stratification on the transition to turbulence in a temporal mixing layer |
title |
The influence of stable stratification on the transition to turbulence in a temporal mixing layer |
spellingShingle |
The influence of stable stratification on the transition to turbulence in a temporal mixing layer Martinez, Denise Maria Varella Stable stratification Direct numerical simulation Mixing layer Buoyancy force, Transition to turbulence |
title_short |
The influence of stable stratification on the transition to turbulence in a temporal mixing layer |
title_full |
The influence of stable stratification on the transition to turbulence in a temporal mixing layer |
title_fullStr |
The influence of stable stratification on the transition to turbulence in a temporal mixing layer |
title_full_unstemmed |
The influence of stable stratification on the transition to turbulence in a temporal mixing layer |
title_sort |
The influence of stable stratification on the transition to turbulence in a temporal mixing layer |
author |
Martinez, Denise Maria Varella |
author_facet |
Martinez, Denise Maria Varella Schettini, Edith Beatriz Camaño Silvestrini, Jorge Hugo |
author_role |
author |
author2 |
Schettini, Edith Beatriz Camaño Silvestrini, Jorge Hugo |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Martinez, Denise Maria Varella Schettini, Edith Beatriz Camaño Silvestrini, Jorge Hugo |
dc.subject.por.fl_str_mv |
Stable stratification Direct numerical simulation Mixing layer Buoyancy force, Transition to turbulence |
topic |
Stable stratification Direct numerical simulation Mixing layer Buoyancy force, Transition to turbulence |
description |
The transition to turbulence in a stably stratified flow is a problem of considerable interest in fluid dynamics with applications in both geophysical sciences and engineering. This transition is controlled by competition between the vertical shear of the base flow and the buoyancy forces due to the density stratification. The present work investigates numerically the effect of stable stratification on the development of a Kelvin-Helmholtz (KH) instability and the formation of streamwise vortices, which are developed after the saturation of the primary billows of KH. The Direct Numerical Simulation (DNS) technique was used to solve the complete Navier-Stokes equations, in the Boussinesq approximation. Numerical tests were done with different Richardson numbers and forced initial conditions for velocity fluctuations. The results showed that high stratification inhibits the pairing process, reduces the buoyancy flux, weakens the vertical motions, decreases the thickness of the mixing layer and affects the formation of streamwise vortices. The three-dimensional results demonstrated that the streamwise vortices are clearly formed in non-stratified cases. In the stratified cases, on the other hand, the streamwise vortices are weakened, due to the streamwise density gradient, which decrease the levels of vorticity in the billows of KH, while increase in the braid zone. |
publishDate |
2006 |
dc.date.issued.fl_str_mv |
2006 |
dc.date.accessioned.fl_str_mv |
2011-10-01T04:19:29Z |
dc.date.available.fl_str_mv |
2011-10-01T04:19:29Z |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.citation.fl_str_mv |
MARTINEZ, D. M. V..; SCHETTINI, E.B. C.; SILVESTRINI, J. H.. The influence of stable stratification on the transition to turbulence in a temporal mixing layer. J. Braz. Soc. Mech. Sci. & Eng. 2006, vol. 28, n. 2, p. 242-252. Disponível em: <http://www.scielo.br/pdf/jbsmse/v28n2/29757.pdf> Acesso em: 30 set. 2011. |
dc.identifier.uri.fl_str_mv |
http://repositorio.furg.br/handle/1/1069 |
dc.identifier.issn.none.fl_str_mv |
1678-5878 |
dc.identifier.doi.pt_BR.fl_str_mv |
10.1590/S1678-58782006000200014 |
identifier_str_mv |
MARTINEZ, D. M. V..; SCHETTINI, E.B. C.; SILVESTRINI, J. H.. The influence of stable stratification on the transition to turbulence in a temporal mixing layer. J. Braz. Soc. Mech. Sci. & Eng. 2006, vol. 28, n. 2, p. 242-252. Disponível em: <http://www.scielo.br/pdf/jbsmse/v28n2/29757.pdf> Acesso em: 30 set. 2011. 1678-5878 10.1590/S1678-58782006000200014 |
url |
http://repositorio.furg.br/handle/1/1069 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.source.none.fl_str_mv |
reponame:Repositório Institucional da FURG (RI FURG) instname:Universidade Federal do Rio Grande (FURG) instacron:FURG |
instname_str |
Universidade Federal do Rio Grande (FURG) |
instacron_str |
FURG |
institution |
FURG |
reponame_str |
Repositório Institucional da FURG (RI FURG) |
collection |
Repositório Institucional da FURG (RI FURG) |
bitstream.url.fl_str_mv |
https://repositorio.furg.br/bitstream/1/1069/1/The%20influence%20of%20stable%20stratification%20on%20the%20transition%20to%20turbulence%20in%20a%20temporal%20mixing%20layer.pdf https://repositorio.furg.br/bitstream/1/1069/2/license.txt |
bitstream.checksum.fl_str_mv |
8a53bf83a118ff09431f1433438ef685 5b92b9704b4f13242d70e45ddef35a68 |
bitstream.checksumAlgorithm.fl_str_mv |
MD5 MD5 |
repository.name.fl_str_mv |
Repositório Institucional da FURG (RI FURG) - Universidade Federal do Rio Grande (FURG) |
repository.mail.fl_str_mv |
|
_version_ |
1798313656567463936 |