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Stability of compressible Ekman boundary-layer flow

Published online by Cambridge University Press:  20 April 2006

Hans Moberg
Affiliation:
Alfa-Laval AB, Tumba, Sweden
Lennart S. Hultgren
Affiliation:
Department of Mechanical Engineering, Illinois Institute of Technology, Chicago, IL 60616
Fritz H. Bark
Affiliation:
Department of Mechanics, Royal Institute of Technology, Stockholm, Sweden

Abstract

The linear stability properties of the Ekman layer in a rapidly rotating gas have been computed numerically. The two types of instability present in an Ekman layer of a homogeneous fluid, which are usually called classes A and B, respectively, are significantly modified by the compressibility. The critical Reynolds number for the class A instability is found to first increase and then decrease for increasing values of the Mach number. The instability waves of class B are monotonically destabilized as the value of the Mach number increases. In addition, a new class of unstable waves appears for a finite value of the Mach number.

Type
Research Article
Copyright
© 1984 Cambridge University Press

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