Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-29T12:29:25.556Z Has data issue: false hasContentIssue false

Longitudinal vortices imbedded in turbulent boundary layers. Part 1. Single vortex

Published online by Cambridge University Press:  20 April 2006

I. M. M. A. Shabaka
Affiliation:
Department of Aeronautics, Imperial College, London Present address: Dept of Aero. Engng, Cairo University
R. D. Mehta
Affiliation:
Department of Aeronautics, Imperial College, London Present address: Dept. of Aero. and Astro., Stanford University, CA.
P. Bradshaw
Affiliation:
Department of Aeronautics, Imperial College, London

Abstract

Detailed mean-flow and turbulence measurements have been made in a low-speed turbulent boundary layer in zero pressure gradient with an isolated, artificially generated vortex imbedded in it. The vortex was generated by a half-delta wing on the floor of the wind-tunnel settling chamber, so that the vortex entering the working section had the same circulation as that originally generated, while axial-component velocity variations were very much reduced, relative to the local mean velocity, from values just behind the generator. The measurements show that the circulation around the vortex imbedded in the boundary layer is almost conserved, being reduced only by the spanwise-component surface shear stress. Therefore the region of flow affected by the vortex continues to grow downstream, its cross-sectional dimensions being roughly proportional to the local boundary-layer thickness. The behaviour of the various components of eddy viscosity, deduced from measured Reynolds stresses, and of the various triple products, suggests that the simple empirical correlations for these quantities used in present-day turbulence models are not likely to yield flow predictions which are accurate in detail.

Type
Research Article
Copyright
© 1985 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bradshaw, P. 1972 Two more low-turbulence wind tunnels driven by centrifugal blowers. Imperial College Aero Rep. 72–10.
Bradshaw, P. 1975 Review – Complex turbulent flow. Trans. ASME I: J. Fluids Engng 97, 146.Google Scholar
Bradshaw, P., Shabaka, I. M. M. A. & Mehta, R. D. 1982 Turbulent vortex flows, final report on ONR contract N 00014-78-G-0032. Imperial College Aero Tech. Note 82–103 (available on microfiche): AD-A124 063/9.
Haines, D. A. & Smith, M. C. 1983 Wind tunnel generation of horizontal roll vortices over a differentially heated surface. Nature 306, 351.Google Scholar
Harvey, J. K. & Perry, F. J. 1971 Flow field produced by trailing vortices in the vicinity of the ground. AIAA J. 9, 1659.Google Scholar
Hoffmann, H. P. 1976 Untersuchung der 3-dimensionalen turbulenten Grenzschicht an einem Schiffsdoppelmodell im Windkanal. Inst. für Schiffbau, Universität Hamburg, Ber. 343.
Hoffmann, P. H., Muck, K. C. & Bradshaw, P. 1984 The effect of concave surface curvature on turbulent boundary layers, submitted to J. Fluid Mech.Google Scholar
Humphrey, J. A. C., Whitelaw, J. H. & Yee, G. 1981 Turbulent flow in a square duct with strong curvature. J. Fluid Mech. 103, 443.Google Scholar
Kline, S. J., Cantwell, B. J. & Lilley, G. M. (eds.) 1981 Proc. 1980–81 AFOSR-HTTM-Stanford Conf. on Complex Turbulent Flows, vol. 1.
Kline, S. J., Cantwell, B. J. & Lilley, G. M. (eds.) 1982 Proc. 1980–81 AFOSR-HTTM-Stanford Conf. on Complex Turbulent Flows, vol. 2.
Larsson, L. (ed.) 1981 SSPA-ITTC Workshop on Ship Boundary Layers 1980. SSPA, Gothenburg, Pub. 90.
Mokhtari, S. & Bradshaw, P. 1983 Longitudinal vortices in wind tunnel wall boundary layers. Aero. J. 87, 233.Google Scholar
Peake, D. J. & Tobak, M. 1980 Three-dimensional interactions and vortical flow with emphasis on high speeds. AGARDograph 252.
Shabaka, I. M. M. A. & Bradshaw, P. 1981 Turbulent flow measurements in an idealized wing/body junction. AIAA J. 19, 131.Google Scholar
Smits, A. J., Young, S. T. B. & Bradshaw, P. 1979 The effect of short regions of high surface curvature on turbulent boundary layers. J. Fluid Mech. 94, 209.Google Scholar
Tanaka, I. & Suzuki, T. 1978 Interaction between the boundary layer and longitudinal vortices. In Proc. Intl Symp. on Ship Resistance, Gothenburg (ed. L. Larsson).
Wieghardt, K. 1983 Kinematics of a wake flow. Z. Flugwiss. Weltraumforsch. 7, 149.Google Scholar
Young, A. D. 1977 Some special boundary layer problems. Z. Flugwiss. Weltraumforsch. 1, 401.Google Scholar