WIT Press


Newton And Quasi-Newton Methods For The Non- Linear Richards Equation

Price

Free (open access)

Volume

24

Pages

8

Published

1998

Size

668 kb

Paper DOI

10.2495/CMWR980722

Copyright

WIT Press

Author(s)

Claudia Fassino and Gianmarco Manzini

Abstract

In this work we investigate the effectiveness and efficiency of Newton, Picard and quasi-Newton linearizations of the non-linear algebraic problem which is originated by an RTo — PQ mixed-hybrid formulation of the 2 — D non-linear Richards' equation. Numerical experiments are shown when the methods are applied to a stationary and a time-dependent benchmark problem. 1 Introduction The Richards equation, which is commonly used in modelizing ground- water flow in partially saturated porous media, can contain some nonlinearities due to pressure head dependencies in the general stor- age term and in the relative hydraulic conductivity. The RT^ — PQ mixed-hybrid formulation, reported in Bergamaschi & Putti [5] a

Keywords