On Wed, 3 Sep 2014, Miguel Angel Salazar de Troya wrote:
> In this paper > > http://arxiv.org/pdf/1009.4975.pdf > > In page 9, at the bottom, they mention this: > > As indicated by the circled nodes in Figure 3(a), level-one mesh > incompatibility results in hanging nodes. The libMesh package handles those > hanging nodes by using the projection method to enforce constraints in the > stiffness matrix This is correct > Since libMesh does not drop the constrained DOFs in the linear system, And this is correct > the projected system in (7) is singular when there is any hanging > node. But this is only correct if they're computing (7) themselves rather than letting libMesh handle it. Depending on the constraint options you select we fill in those zero blocks with the constraint equations themselves or with ones on the diagonal. --- Roy ------------------------------------------------------------------------------ Slashdot TV. Video for Nerds. Stuff that matters. http://tv.slashdot.org/ _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
