kth.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Separating large-scale superposition and modulation in turbulent channels
Karlsruhe Inst Technol, Inst Fluid Mech, Kaiserstr 10, D-76131 Karlsruhe, Germany..
Karlsruhe Inst Technol, Inst Fluid Mech, Kaiserstr 10, D-76131 Karlsruhe, Germany..
KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Fluid Mechanics and Engineering Acoustics. (SimEx)ORCID iD: 0000-0001-6570-5499
KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Fluid Mechanics and Engineering Acoustics. Karlsruhe Inst Technol, Karlsruhe, Germany.. (SimEx)ORCID iD: 0000-0002-1663-3553
Show others and affiliations
2023 (English)In: Journal of Fluid Mechanics, ISSN 0022-1120, E-ISSN 1469-7645, Vol. 958, article id A37Article in journal (Refereed) Published
Abstract [en]

The presence of very-large-scale motions in wall-bounded turbulent flows is commonly associated with their footprint in the form of the superposition of the large scales at the wall and the additional amplitude modulation of small-scale near-wall turbulence. These two phenomena are currently understood to be interlinked, with the superposed large-scale velocity gradient causing the modulation of small-scale activity in the proximity of the wall. To challenge this idea, we devise a numerical strategy that selectively suppresses either superposition or amplitude modulation, in an effort to isolate and study the remaining phenomenon. Results from our direct numerical simulations indicate that a positive correlation between the amplitude of the small scales in the near-wall region and the large-scale signal in the outer flow persists even when near-wall large-scale motions are suppressed - i.e. in absence of superposition. Clearly, this kind of correlation cannot be caused by the near-wall large-scale velocity or its gradients, as both are absent. Conversely, when modulation is blocked, the near-wall footprints of the large scales seem to disappear. This study has been carried out on channel flows at friction Reynolds number Re-tau = 1000 in both standard simulation domains and minimal streamwise units (MSUs), where the streamwise fluctuation energy is enhanced. The consistency of the results obtained by the two approaches suggests that MSUs can capture correctly this kind of scale interaction at a much reduced cost.

Place, publisher, year, edition, pages
Cambridge University Press (CUP) , 2023. Vol. 958, article id A37
Keywords [en]
turbulence theory, turbulent boundary layers
National Category
Fluid Mechanics
Identifiers
URN: urn:nbn:se:kth:diva-325261DOI: 10.1017/jfm.2023.103ISI: 000949227800001Scopus ID: 2-s2.0-85150245546OAI: oai:DiVA.org:kth-325261DiVA, id: diva2:1748705
Note

QC 20230404

Available from: 2023-04-04 Created: 2023-04-04 Last updated: 2025-02-09Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textScopus

Authority records

Vinuesa, RicardoÖrlü, RamisSchlatter, Philipp

Search in DiVA

By author/editor
Vinuesa, RicardoÖrlü, RamisSchlatter, Philipp
By organisation
Linné Flow Center, FLOWFluid Mechanics and Engineering Acoustics
In the same journal
Journal of Fluid Mechanics
Fluid Mechanics

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 208 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf