Sorry I should have been more specific. I meant if libmesh could support the type of adaptive mesh refinement that avoids hanging nodes. I have read that this creates more degrees of freedom as the refinement propagates through the mesh and that it might be better to deal with the hanging nodes instead.
In Demkowicz's book, they work only with 1-irregular mesh refinement algorithms, is this also the case for libmesh? On Wed, May 28, 2014 at 9:18 AM, Paul T. Bauman <[email protected]> wrote: > On Tue, May 27, 2014 at 5:02 PM, Miguel Angel Salazar de Troya < > [email protected]> wrote: > >> >> I am going to try to implement these functions with the LAGRANGE_VEC >> because it would work better for me. >> > > OK, great! > > >> So I have the first questions: >> >> Function compute_proj_constraints. I understand it imposes a constraint >> on the hanging nodes so they have a value related to their side neighboring >> nodes. How are they related? Linear interpolation? >> > > They are related by enforcing continuity. You'll see that, for example, C1 > continuous elements enforce both function and derivative continuity. For > HDiv and HCurl, it'll be different (normal and tangential, respectively). > > >> Do you know of a paper or document where this projection is >> mathematically written? >> > > Closest I've seen is in Leszek Demkowicz's books (but those are really > focused on his code). You might also look at some of Abani Patra's papers > (oriented towards hp, but may still be useful). @roystgnr, @benkirk, and > @jwpeterson might also have some suggestions. What's done is adding an > equation to the global system that enforces this continuity. Have a look at > src/fe/fe_lagrange.C, lagrange_compute_constraints. You see that dofs get > inserted into the constraint row. If you wanted to generalize this for > LAGRANGE_VEC, I wouldn't be opposed; IIRC, I was going to try and write the > compute_proj_constraints to be more general and have everyone call that, > but it may be simpler for you to just do an analog of the Lagrange case. > @roystgnr, opinions? > > >> With regards to this issue, could it be easier to do adaptive mesh >> refinement on unstructured grids? Does libmesh support this? >> > > This is what libMesh does. I'm not sure I understand the question. > > Best, > > Paul > -- *Miguel Angel Salazar de Troya* Graduate Research Assistant Department of Mechanical Science and Engineering University of Illinois at Urbana-Champaign (217) 550-2360 [email protected] ------------------------------------------------------------------------------ Learn Graph Databases - Download FREE O'Reilly Book "Graph Databases" is the definitive new guide to graph databases and their applications. Written by three acclaimed leaders in the field, this first edition is now available. Download your free book today! http://p.sf.net/sfu/NeoTech _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
