Tau-adaptivity for nonsmooth processes in heterogeneous media

Monday, 15 December 2014
Jed Brown, Argonne National Laboratory, Argonne, IL, United States, Mark Adams, Lawrence Berkeley National Laboratory, Berkeley, CA, United States and Matthew Knepley, Univ of Chicago, CHICAGO, IL, United States
We propose a form of adaptivity based on FAS multigrid and related to the "frozen τ technique proposed by Achi Brandt, allowing fine grid work to be avoided in regions with nearly-linear behavior, despite arbitrarily rough coefficients. We investigate indicators for reuse of τ, practicality of dynamic load balancing, and experiment with localized plastic yielding in lithosphere dynamics.