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Lee waves in a stratified flow Part 3. Semi-elliptical obstacle

Published online by Cambridge University Press:  28 March 2006

Herbert E. Huppert  and
John W. Miles
Herbert E. Huppert
Affiliation:
Also Department of Aerospace and Mechanical Engineering Sciences.
John W. Miles
Affiliation:
Institute of Geophysics and Planetary Physics University of California, La Jolla Also Department of Aerospace and Mechanical Engineering Sciences.
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Abstract

The stratified shear flow over a two-dimensional obstacle of semi-elliptical crosssection is considered. The shear flow is assumed to be inviscid with constant upstream values of the density gradient and dynamic pressure (Long's model). Two complete sets of lee-wave functions, each of which satisfies the condition of no upstream reflexion, are determined in elliptic co-ordinates for ε ≤ 1 and ε ≥ 1, where ε is the ratio of height to half-width of the obstacle. These functions are used to determine the lee-wave field produced by, and the consequent drag on, a semi-elliptical obstacle as functions of ε and the reduced frequency (reciprocal Froude number) within the range of stable flow. The reduced frequency at which static instability first occurs is calculated as a function of ε.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 35 , Issue 3 , 20 February 1969 , pp. 481 - 496
Copyright
© 1969 Cambridge University Press

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References

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