On Tue, 27 Apr 2010, Boyce Griffith wrote: > On 4/27/10 10:20 PM, Roy Stogner wrote: >> >> On Tue, 27 Apr 2010, Boyce Griffith wrote: >> >>> I am trying to use the DofMap to impose Dirichlet-type boundary >>> conditions within an explicit nonlinear mechanics solver which is >>> embedded in a larger fluid-structure interaction solver. I constrain >>> the velocity and force DOFs at Dirichlet boundaries to be zero by adding >>> a DofConstraintRow for each of the constrained DOFs. >> >> This should be a good method for homogeneous constraints on LAGRANGE >> (or HIERARCHIC, or pretty much anything but CLOUGH) elements. I don't >> know if anyone's ever actually tested using it before, though. > > I don't expect to be using anything other than LAGRANGE for a while... > > After adding DofConstraintRow's to the dof map, what generally needs to be > (re-)initialized? Is it a good idea to call EquationSystems::reinit()?
The difficulty is in how you add the rows - it needs to be done in user_constrain(), which gets called by EquationSystems::reinit(). If you do it any earlier your rows are probably going to be deleted when we construct the geometric/periodic constraints, and if you do it any later then your rows might not be taken into account properly during expansion of constraints. > I was certainly surprised... I'll try to verify that this is the only > difference between the working and non-working cases and see if I can put > together a simple example. Thanks, --- Roy ------------------------------------------------------------------------------ _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
