Oblique laminar-turbulent interfaces in plane shear flows
2013 (English)In: Physical Review Letters, ISSN 0031-9007, Vol. 110, no 3, 034502- p.Article in journal (Refereed) Published
Localized structures such as turbulent stripes and turbulent spots are typical features of transitional wall-bounded flows in the subcritical regime. Based on an assumption for scale separation between large and small scales, we show analytically that the corresponding laminar-turbulent interfaces are always oblique with respect to the mean direction of the flow. In the case of plane Couette flow, the mismatch between the streamwise flow rates near the boundaries of the turbulence patch generates a large-scale flow with a nonzero spanwise component. Advection of the small-scale turbulent fluctuations (streaks) by the corresponding large-scale flow distorts the shape of the turbulence patch and is responsible for its oblique growth. This mechanism can be easily extended to other subcritical flows such as plane Poiseuille flow or Taylor-Couette flow.
Place, publisher, year, edition, pages
2013. Vol. 110, no 3, 034502- p.
In-plane shear, Large-scale flows, Localized structures, Plane Couette flow, Plane Poiseuille flow, Scale separation, Small scale, Subcritical flow, Taylor Couette flow, Turbulent fluctuation, Turbulent spots, Wall bounded flows
Other Physics Topics
IdentifiersURN: urn:nbn:se:kth:diva-118208DOI: 10.1103/PhysRevLett.110.034502ISI: 000313422400008ScopusID: 2-s2.0-84872340616OAI: oai:DiVA.org:kth-118208DiVA: diva2:605097
QC 201302132013-02-132013-02-132013-02-22Bibliographically approved