The effect of curvature on boundary layers subjected to strong adverse pressure gradients

L. Cullen, B. Nishri, D. Greenblatt, Israel J Wygnanski

Research output: Chapter in Book/Report/Conference proceedingConference contribution

3 Citations (Scopus)

Abstract

Two separate but complimentary experiments were conducted in turbulent boundary layers subjected to severe adverse pressure gradients: one developed over a flat surface, while the other had streamwise concave surface curvature. Measurements of surface pressures, as well as streamwise mean and fluctuating velocities,' established that gross characteristics of the boundary layer such as shape factor and skin friction coefficient were comparable. Detailed profile measurements normal to the wall, demonstrated that the most tangible evidence of the effect of curvature is that turbulence quantities do not scale with local boundary layer integral length scales, while on flat surfaces they do. On the flat surface, the measurement of streamwise cross-correlations showed that the spanwise wavelength of non-stationary three-dimensional structures did not increase. In contrast, curvature brought about an increase in the cross-stream wavelength. This behavior is consistent with the existence of a weak centrifugal or GOrtler-type instability mechanism of the type predicted by stability theory. The main conclusion was that concave surface curvature, whose effect is generally considered to be secondary to that of a strong adverse pressure gradient, plays a very significant role in the behavior of flow approaching separation.

Original languageEnglish (US)
Title of host publication40th AIAA Aerospace Sciences Meeting and Exhibit
StatePublished - 2002
Event40th AIAA Aerospace Sciences Meeting and Exhibit 2002 - Reno, NV, United States
Duration: Jan 14 2002Jan 17 2002

Other

Other40th AIAA Aerospace Sciences Meeting and Exhibit 2002
CountryUnited States
CityReno, NV
Period1/14/021/17/02

Fingerprint

Pressure gradient
pressure gradients
pressure gradient
curvature
boundary layers
Boundary layers
boundary layer
flat surfaces
flow separation
friction factor
skin friction
turbulent boundary layer
wavelength
wavelengths
coefficient of friction
cross correlation
surface pressure
Wavelength
Flow separation
Skin friction

ASJC Scopus subject areas

  • Space and Planetary Science
  • Aerospace Engineering

Cite this

Cullen, L., Nishri, B., Greenblatt, D., & Wygnanski, I. J. (2002). The effect of curvature on boundary layers subjected to strong adverse pressure gradients. In 40th AIAA Aerospace Sciences Meeting and Exhibit

The effect of curvature on boundary layers subjected to strong adverse pressure gradients. / Cullen, L.; Nishri, B.; Greenblatt, D.; Wygnanski, Israel J.

40th AIAA Aerospace Sciences Meeting and Exhibit. 2002.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Cullen, L, Nishri, B, Greenblatt, D & Wygnanski, IJ 2002, The effect of curvature on boundary layers subjected to strong adverse pressure gradients. in 40th AIAA Aerospace Sciences Meeting and Exhibit. 40th AIAA Aerospace Sciences Meeting and Exhibit 2002, Reno, NV, United States, 1/14/02.
Cullen L, Nishri B, Greenblatt D, Wygnanski IJ. The effect of curvature on boundary layers subjected to strong adverse pressure gradients. In 40th AIAA Aerospace Sciences Meeting and Exhibit. 2002
Cullen, L. ; Nishri, B. ; Greenblatt, D. ; Wygnanski, Israel J. / The effect of curvature on boundary layers subjected to strong adverse pressure gradients. 40th AIAA Aerospace Sciences Meeting and Exhibit. 2002.
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