TY - GEN A1 - Kornhuber, Ralf T1 - Globally Convergent Multigrid Methods for Porous Medium Type Problems N2 - We consider the fast solution of large, piecewise smooth minimization problems as typically arising from the finite element discretization of porous media flow. For lack of smoothness, usual Newton multigrid methods cannot be applied. We propose a new approach based on a combination of convex minization with {\em constrained} Newton linearization. No regularization is involved. We show global convergence of the resulting monotone multigrid methods and give logarithmic upper bounds for the asymptotic convergence rates. T3 - ZIB-Report - SC-97-45 Y1 - 1997 UR - https://opus4.kobv.de/opus4-zib/frontdoor/index/index/docId/314 UR - https://nbn-resolving.org/urn:nbn:de:0297-zib-3142 ER -