UNIVERSITY OF COLORADO AT DENVER

PLACE: Mathematics Conference Room 656 UCD Building, 1250 14th St., Denver

TIME: noon (Refreshments served at 11:45 am)

DATE: November 5, 1998

Iterative analysis of Finite Element methods on non-matching grids 

                     Yuri  Kuznetsov

                   Department of Mathematics
                     University of Houston
                              &
                Institute of Numerical Mathematics
                 Russian Academy of Sciences
                          Moscow


     Abstract:Macro-hybrid finite element methods based on nonoverlapping
    and/or overlapping domain decomposition result in algebraic problems
    with symmetric matrices of the saddle point form. It is well known that
    symmetric positive definite block diagonal matrices are good candidates
    for preconditioning of saddle point matrices.
    The talk is concerned with designing of efficient parallel block
    diagonal preconditioners for matrices which arise from macro-hybrid
    finite element discretizations of elliptic s.p.d.problems with non-
    matching grids on the interfaces between subdomains. It is proved that in
    in the case of regular and quasiuniform subdomain grids the proposed
    preconditioners are spectrally equivalent to the system matrices and
    have the optimal order of arithmetical complexity.
    Numerical result for selected test cases as well as applications
    to numerical simulation of fluid flows are presented.