Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-18T19:09:56.788Z Has data issue: false hasContentIssue false

Organized structures in a reattaching separated flow field

Published online by Cambridge University Press:  20 April 2006

T. R. Troutt
Affiliation:
Department of Mechanical Engineering, Washington State University, Pullman, WA 99164–2920
B. Scheelke
Affiliation:
Department of Mechanical Engineering, Washington State University, Pullman, WA 99164–2920
T. R. Norman
Affiliation:
Department of Mechanical Engineering, Washington State University, Pullman, WA 99164–2920

Abstract

Spanwise structures in a two-dimensional reattaching separated flow were studied using multisensor hot-wire anemometry techniques. The results of these measurements strongly support the existence and importance of large-scale vortices in both the separated and reattached regions of this flow. Upstream of reattachment, vortex pairings are indicated and the spanwise structures attain correlation scales closely comparable to previously measured mixing-layer vortices. These large-scale vortices retain their organization far downstream of the reattachment region. However, pairing interactions appear to be strongly inhibited in this region. It is suggested that large-scale vortex dynamics are primarily responsible for some of the important time-averaged features of this flow. Notably, the reduction of turbulence energy in the reattachment region and the slow transition of the mean flow downstream of reattachment are attributed to effects associated with these vortices.

Type
Research Article
Copyright
© 1984 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

Browand, F. K. & Ho, C. M. 1983 The mixing layer: an example of quasi two-dimensional turbulence. J. Méc. Théor. Appl., Special Suppl. pp. 99120.Google Scholar
Browand, F. K. & Latigo, B. O. 1979 Growth of the two-dimensional mixing layer from a turbulent and nonturbulent boundary layer. Phys. Fluids 92, 10111019.Google Scholar
Browand, F. K. & Troutt, T. R. 1980a A note on spanwise structure in the two-dimensional mixing layer. J. Fluid Mech. 97, 771781.Google Scholar
Browand, F. K. & Troutt, T. R. 1980b The geometry of the large scale structure of the turbulent mixing layer. In Proc. 15th Intl Congr. Theor. Appl. Mech., Univ. Toronto.
Browand, F. K. & Troutt, T. R. 1983 The turbulent mixing layer: geometry of large vortices. Submitted to J. Fluid Mech.Google Scholar
Browand, F. K. & Weidman, P. D. 1976 Large scales in the developing mixing layer. J. Fluid Mech. 76, 127144.Google Scholar
Brown, G. L. & Roshko, A. 1974 On density effects and large structure in turbulent mixing layers. J. Fluid Mech. 64, 775816.Google Scholar
Chandrsuda, C. & Bradshaw, P. 1981 Turbulence structure of a reattaching mixing layer. J. Fluid Mech. 110, 171194.Google Scholar
Eaton, J. K. & Johnston, J. P. 1981 A review of research on subsonic turbulent flow reattachment. AIAA J. 19, 10931100.Google Scholar
Gad-el-Hak, M., Blackwelder, R. F. & Ho, C. M. 1983 Coherent structures in steady and unsteady motions of a delta wing. Bull. Am. Phys. Soc., Ser. II 28, 1397.Google Scholar
Klebanoff, P. S. 1955 Characteristics of turbulence in a boundary layer with zero pressure gradient. NACA Rep. 1247.Google Scholar
Kuehn, D. M. 1980 Effects of adverse pressure gradient on the incompressible reattaching flow over a rearward-facing step. AIAA J. Tech. Note 18, 3.Google Scholar
Oster, D. & Wygnanski, I. 1982 The forced mixing layer between parallel streams. J. Fluid Mech. 123, 91130.Google Scholar
Perry, A. E. & Chang, M. S. 1982 On the mechanism of wall turbulence. J. Fluid Mech. 119, 173217.Google Scholar
Winant, C. D. & Browand, F. K. 1974 Vortex pairing: the mechanism of turbulent mixing layer growth at moderate Reynolds number. J. Fluid Mech. 63, 327361.Google Scholar