On a Nonlinear Degenerate Parabolic Equation in Infiltration or Evaporation through a Porous Medium.

Abstract

During the last two decades a great deal of progress has been made on the mathematical analysis of flows through porous media. Such phenomena led to degenerate nonlinear parabolic equations. The equations obtained are of different nature when the fluid movement takes place in a horizontal column of the medium rather than in a vertical column of the medium. The latter case gives rise to first order nonlinear perturbations of the former case and equations of this more general sort also model the evaporation of a fluid through a porous medium. A significant technical difficulty arises in the evaporation case; the first order nonlinear terms can be singular at the points where the solution vanishes. In this paper the authors give a mathematical treatment of the Cauchy problem as well as the first and mixed boundary value problems for the relevant equations. Existence, continuity and uniqueness of generalized solutions are proved thereby improving earlier results in the mathematical literature.

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Document Details

Document Type
Technical Report
Publication Date
Apr 01, 1983
Accession Number
ADA129186

Entities

People

  • J. Ildefonso Diaz
  • Robert Kersner

Organizations

  • University of Wisconsin–Madison

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  • C4I

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  • Banach Space
  • Boundaries
  • Boundary Value Problems
  • Cauchy Problem
  • Continuity
  • Equations
  • Integrals
  • Mathematical Analysis
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  • Nonlinear Analysis
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Fields of Study

  • Mathematics

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  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Plasma Physics / Magnetohydrodynamics