Applying the boundary-layer independence principle to turbulent flows

Israel J Wygnanski, Philipp Tewes, Lutz Taubert

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Velocities measured in turbulent boundary layers over yawed flat plates confirmed that the mean velocity profiles normal to the leading edge are proportional to the velocity profiles parallel to it, with a proportionality constant depending on the yaw angle. This turned out to be the necessary and sufficient condition to make the wall stress components normal and parallel to the leading edge also proportional in the same manner, thus reaffirming the boundary-layer independence principle for turbulent and laminar flows alike. Reinterpretation of old experiments thus changed the mantra stating, "the independence principle does not apply to turbulent flow", thus providing a new insight into three-dimensional boundary-layer flows on yawed, high-aspect-ratio wings. It explains the prevalence of attached spanwise flow near the trailing edges of such wings, and it provides a rationale for turbulence modeling on them. Furthermore, it indicates the direction along which active separation control should take place.

Original languageEnglish (US)
Pages (from-to)175-182
Number of pages8
JournalJournal of Aircraft
Volume51
Issue number1
DOIs
StatePublished - Jan 2014

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Turbulent flow
Boundary layers
Boundary layer flow
Laminar flow
Aspect ratio
Turbulence
Experiments

ASJC Scopus subject areas

  • Aerospace Engineering

Cite this

Applying the boundary-layer independence principle to turbulent flows. / Wygnanski, Israel J; Tewes, Philipp; Taubert, Lutz.

In: Journal of Aircraft, Vol. 51, No. 1, 01.2014, p. 175-182.

Research output: Contribution to journalArticle

Wygnanski, Israel J ; Tewes, Philipp ; Taubert, Lutz. / Applying the boundary-layer independence principle to turbulent flows. In: Journal of Aircraft. 2014 ; Vol. 51, No. 1. pp. 175-182.
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