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Computational analysis of unsteady supersonic cavity flows driven by thick shear layers

Published online by Cambridge University Press:  04 July 2016

X. Zhang
Affiliation:
Department of Engineering, University of Cambridge
J. A. Edwards
Affiliation:
Department of Engineering, University of Cambridge

Abstract

Supersonic cavity flows driven by a thick shear layer at Mach 1·5 and 2·5 are studied by solving the two-dimensional unsteady compressible Navier-Stokes equations in terms of mass-averaged variables. The length to depth ratio of the rectangular cavity is three. The numerical scheme used is the finite-difference algorithm by Brailovskaya. A two-layer eddy-viscosity turbulence model is used. The results are compared with experimental data. The computations show the self-sustained oscillations at Mach 1·5 and 2·5. The continuous formation and downstream shedding of leading edge vortices is demonstrated. The oscillatory modes are correctly predicted. The first mode is attributed to a large unsteady trailing edge vortex moving in the transverse direction. Based on the analysis, it is considered that the oscillation in the length to depth ratio three cavity is a longitudinal one and is controlled by a fluid dynamic mechanism rather than a purely acoustic one.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1988 

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Footnotes

*

Now in the Dept. of Aeronautics and Astronautics, University of Southampton

Now at the College of Aeronautics, Cranfield Institute of Technology, Cranfield, Bedford

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