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Flow focusing instability in a solidifying mushy layer

Published online by Cambridge University Press:  26 April 2006

A. O. P. Chiareli  and
M. Grae Worster
A. O. P. Chiareli
Affiliation:
Institute of Theoretical Geophysics, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK
M. Grae Worster
Affiliation:
Institute of Theoretical Geophysics, Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge CB3 9EW, UK
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Abstract

The stability of the flow of interstitial liquid in a mushy layer driven by expansion or contraction upon solidification is analysed. The full perturbation equations are reduced in a particular aymptotic limit that allows the principal mechanisms controlling instability to be identified. Comparisons are made with the acid-etching instabilities in porous rocks. The full equations are then solved to determine the parametric dependences of the instability. It is found that, though the potential for instability exists, it is unlikely to occur in practice.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 297 , 25 August 1995 , pp. 293 - 305
Copyright
© 1995 Cambridge University Press

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