Re: [Libmesh-users] Constraint matrix

[Renato P. <re...@gm...>]

> You could get the dof coefficients corresponding to a du/dx (get dphi
> for each shape function at the point where you want a gradient
> evaluation, take the x component of each) and insert them into a
> constraint row, but this is not likely to be the most accurate way to
> solve your problem.  Not sure what you're solving (contact?  porous
> media flow?)
Porous media flow (pressure and displacements)

> but there's probably a formulation out there somewhere
> which enforces a pressure-strain relationship weakly rather than with
> point-by-point constraint equations.
I guess I found something in the boundary integrals that come out of
the green theorem.

You are right - I was certainly in the wrong direction.
I believe I'm getting back to track now...

Thanks!
Renato