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Solutions of the porous medium equation with degenerate interfaces

Published online by Cambridge University Press:  07 December 2012

J. IAIA
Affiliation:
University of North Texas, Denton, TX 76203, US emails: [email protected], [email protected]
S. BETELU
Affiliation:
University of North Texas, Denton, TX 76203, US emails: [email protected], [email protected]

Abstract

We prove the existence of a one-parameter family of solutions of the porous medium equation in which the interface is a half line whose end point advances at a constant speed. Then we prove the stability of the solutions under a suitable class of perturbations. We discuss the relevance of these solutions to gravity-driven flows of thin films, and show that some solutions develop a very thin triangular plateau in the direction of propagation and that the angle of the plateau and its thickness are decreasing functions of the speed.

Type
Papers
Copyright
Copyright © Cambridge University Press 2012

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