Hostname: page-component-6bf8c574d5-w79xw Total loading time: 0 Render date: 2025-02-25T12:03:34.885Z Has data issue: false hasContentIssue false
  • English
  • Français

Experimental and numerical investigation of the kinematic theory of unsteady separation

Published online by Cambridge University Press:  25 September 2008

M. WELDON ,
T. PEACOCK ,
G. B. JACOBS ,
M. HELU  and
G. HALLER
M. WELDON
Affiliation:
Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm 1-310, Cambridge, MA 02139, USAtomp@mit.edu
T. PEACOCK
Affiliation:
Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm 1-310, Cambridge, MA 02139, USAtomp@mit.edu
G. B. JACOBS
Affiliation:
Department of Aerospace Engineering & Engineering Mechanics, San Diego State University, 5500 Campanile Drive, San Diego, CA 92182, USA
M. HELU
Affiliation:
Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm 1-310, Cambridge, MA 02139, USAtomp@mit.edu
G. HALLER
Affiliation:
Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Ave., Rm 1-310, Cambridge, MA 02139, USAtomp@mit.edu
Get access Rights & Permissions [Opens in a new window]

Abstract

We present the results of a combined experimental and numerical study of flow separation in the unsteady two-dimensional rotor-oscillator flow. Experimentally detected material spikes are directly compared to separation profiles predicted from numerical shear-stress and pressure data, using a recent kinematic theory of unsteady separation. For steady, periodic, quasi-periodic and random forcing, fixed separation is observed, and experimental observations and theoretical predictions are in close agreement. The transition from fixed to moving separation is also reported.

Type
Papers
Information
Journal of Fluid Mechanics , Volume 611 , 25 September 2008 , pp. 1 - 11
Copyright
Copyright © Cambridge University Press 2008

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

REFERENCES

Van Dommelen, L. L. & Shen, S. F. 1982 The genesis of separation. In Numerical and Physical Aspects of Aerodynamics Flow (ed. Cebici, T.), pp. 283–311. Long Beach, California.Google Scholar
Fumagalli, M. 2002 A numerical investigation of particle motion and deposition on a cross oscillating cylinder. MS thesis, University of Illinois at Chicago.Google Scholar
Hackborn, W. W., Ulucakli, M. E. & Yuster, T. 1997 A theoretical and experimental study of hyperbolic and degenerate mixing regions in a chaotic Stokes flow. J. Fluid Mech. 346, 23–48.CrossRefGoogle Scholar
Haller, G. 2004 Exact theory of unsteady separation for two-dimensional flows. J. Fluid Mech. 512, 257–311.CrossRefGoogle Scholar
Horton, H. P. 1968 Laminar separation bubble in two- and three-dimensional incompressible flow. PhD thesis, University of London.Google Scholar
Kilic, M. S., Haller, G. & Neishtadt, A. 2005 Unsteady fluid slow separation by the method of averaging. Phys. Fluids 17, 067104CrossRefGoogle Scholar
Lighthill, M. J. 1963 Boundary layer theory. In Laminar Boundary Layers (ed. Rosenhead, L.). Dover.Google Scholar
Liu, C. S. & Wan, Y.-H. 1985 A simple exact solution of the Prandtl boundary layer equations containing a point of separation. Arch. Rat. Mech. Anal. 89, 177–185.CrossRefGoogle Scholar
Moffatt, H. K. 1964 Viscous and resistive eddies near a sharp corner. J. Fluid Mech. 18, 1–18.Google Scholar
Prandtl, L. 1904 Über Flüssigkeitsbewegung bei sehr kleiner Reibung. Verh. III, Int. Math. Kongr., Heidelberg, pp. 484–491.Google Scholar
Sears, W. R. & Telionis, D. P. 1975 Boundary-layer separation in unsteady flow. SIAM J. Appl. Maths 28, 215–235.CrossRefGoogle Scholar
Shariff, K., Pulliam, T. H. & Ottino, J. M. 1991 A dynamical systems analysis of kinematics in the time-periodic wake of a circular cylinder. Lect. Appl. Math. 28, 613–646.Google Scholar
Surana, A., & Haller, G. 2008 Ghost manifolds in slow-fast systems, with an application to unsteady fluid flow separation. Physica D 237, 1507–1529.Google Scholar
Surana, A., Jacobs, G., Grunberg, O. & Haller, G. 2008 Exact theory of fixed unsteady separation in three-dimensional flows. Phys. Fluids (to appear).Google Scholar
Sychev, V. V., Ruban, A., Sychev, V. V. & Korolev, G. L. 1998 Asymptotic Theory of Separated Flows. Cambridge University Press.CrossRefGoogle Scholar
Yuster, T. & Hackborn, W. W. 1997 On invariant manifolds attached to oscillating boundaries of Stokes flows. Chaos 7, 769–776.CrossRefGoogle ScholarPubMed