Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-19T19:05:37.095Z Has data issue: false hasContentIssue false
  • English
  • Français

Three-dimensional instability in flow over a backward-facing step

Published online by Cambridge University Press:  13 December 2002

DWIGHT BARKLEY ,
M. GABRIELA M. GOMES  and
RONALD D. HENDERSON
DWIGHT BARKLEY
Affiliation:
Mathematics Institute, University of Warwick, Coventry CV4 7AL, UK
M. GABRIELA M. GOMES
Affiliation:
Mathematics Institute, University of Warwick, Coventry CV4 7AL, UK
RONALD D. HENDERSON
Affiliation:
Aeronautics and Applied Mathematics, California Institute of Technology, Pasadena, CA 91125, USA
Get access Rights & Permissions [Opens in a new window]

Abstract

Results are reported from a three-dimensional computational stability analysis of flow over a backward-facing step with an expansion ratio (outlet to inlet height) of 2 at Reynolds numbers between 450 and 1050. The analysis shows that the first absolute linear instability of the steady two-dimensional flow is a steady three-dimensional bifurcation at a critical Reynolds number of 748. The critical eigenmode is localized to the primary separation bubble and has a flat roll structure with a spanwise wavelength of 6.9 step heights. The system is further shown to be absolutely stable to two-dimensional perturbations up to a Reynolds number of 1500. Stability spectra and visualizations of the global modes of the system are presented for representative Reynolds numbers.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 473 , 10 December 2002 , pp. 167 - 190
Copyright
© 2002 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.)