A Two-Grid Method for Mixed Finite-Element Solution of Reaction-Di usion Equations
نویسندگان
چکیده
We present a scheme for solving two-dimensional, nonlinear reaction-diiusion equations, s @p @t ? r (Krp) = f (p); using a mixed nite-element method. To linearize the mixed-method equations, we use a two grid scheme that relegates all of the Newton-like iterations to a grid 4H much coarser than the original one 4h, with no loss in order of accuracy so long as the mesh sizes obey H = O(p h). The use of a multigrid-based solver for the indeenite linear systems that arise at each coarse-grid iteration, as well as for the similar system that arises on the ne grid, allows for even greater eeciency. c
منابع مشابه
Two-Grid Methods for Mixed Finite-Element Solution of Coupled Reaction-Di usion Systems
We develop two-grid schemes for solving nonlinear reaction-diiusion systems , @p @t ? r (Krp) = f(x; p); where p = (p; q) is an unknown vector-valued function. The schemes use discretizations based on a mixed nite-element method. The two-grid approach yields iterative procedures for solving the nonlinear discrete equations. The idea is to relegate all of the Newton-like iterations to grids much...
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