>> Oh, my mistake, I just needed to add system.mesh_position_set() after >> system.time_solver->advance_timestep(). It works nicely now, cool! > > No, that's not your mistake, that's mine - mesh_position_set() ought > to be handled transparently by the library. The trick is trying to > figure out how to do that most modularly. Doing it in > advance_timestep() is out because we want it to work right in steady > solves too. Doing it in FEMSystem::solve() is probably most > reasonable; I'm just not 100% sure that won't mess up the way > TwoStepTimeSolver works. > > But hey, since ALE is in a known broken state anyway we might as well > move it to "less broken". I'll add the mesh_position_set() to SVN > now. > > > Next step is getting it working with MPI on SerialMesh. If we > construct a SERIAL vector in mesh_position_set, localize solution onto > it, swap it with current_local_solution, and then swap it back and > let it destruct when we're done, that ought to be a sufficient hack... > > But what I'd rather do is fix it for SerialMesh and ParallelMesh at > once. Change mesh_position_set to work only on local active elements, > do a Parallel::sync_dofobject_data_by_id to grab the new locations for > every other node, then loop over nonlocal nodes to set them. I ought > to have some time to try this out next week.
These ideas sound good. > The numerical jacobian verification should give false positive failure > reports, yeah. > > You've still got a CFDLab login, right? Check out > ~roystgnr/pecos/ale/doc/paper.pdf for some discussion of the problem. > Basically there's no way to fix it for existing codes, but the most > straightforward fix wouldn't take too much in the way of application > changes and would also make it easy to add well-modularized > Petrov-Galerkin method support at the library level, so that's at > least on the long-term TODO list. OK, great, thanks for the link, that paper looks enlightening. Dave ------------------------------------------------------------------------------ _______________________________________________ Libmesh-devel mailing list Libmesh-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-devel
