> But.... you don't necessarily have to put the exact _right_ thing either. > There is some grey area here... and what works for one system of equations > won't work for another. In general, if you put something resembling the > true jacobian in there... it will greatly help your linear solves.
>From the finite volume world, it is often common that a 1st-order accurate discretization is used to precondition.... I'd be interested to see what work has been done with DG taking a similar approach - preconditioning with lower P. It is a bit harder here, though, 'cus you need an additional restriction from your larger residual to your preconditioner. In FV the number of unknowns is the same for P=1 or P=2, it is just that the implicit operator stencil grows... -Ben ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
