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Experimental and numerical investigation of the kinematic theory of unsteady separation

Published online by Cambridge University Press:  25 September 2008

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

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
Copyright
Copyright © Cambridge University Press 2008

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