Adaptive Hybrid Mixed Finite Element Discretization of Instationary Variably Saturated Flow in Porous Media

  • P. Knabner
  • E. Schneid
Part of the Lecture Notes in Computational Science and Engineering book series (LNCSE, volume 21)


For the Richards equation, a nonlinear elliptic-parabolic partial differential equation modelling saturated-unsaturated flow in porous media, we present a hybrid mixed finite element discretization. The efficiency of the algorithm is improved by local time step and grid adaption. The adaption algorithms are based on rigorous error estimators, whose derivation is indicated. Examples elucidate the performance of the algorithm


Multigrid Method Time Step Size Mixed Finite Element Error Indicator Richardson Extrapolation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • P. Knabner
    • 1
  • E. Schneid
    • 1
  1. 1.University of Erlangen-NürnbergInstitute of Applied MathematicsErlangenGermany

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