On Sat, 12 Sep 2009, Ted Kord wrote: > The problem I actually have is that there's a concentrated load at a single > point, say x = 16 (domain: 0 < x < 20) which is represented mathematically > as : > > -0.5 - 30 * dirac-delta(x-16) > > As far as I know, this, i.e., -30 will have to be applied as a Neumann B.C > at that point.
Ah, I understand now - you're not trying to enforce a derivative at that point, you're trying to enforce a derivative jump discontinuity at that point. You're doing it right, then. I'm just not used to thinking of that as a Neumann condition, since variational forms make dirac deltas just look like any other forcing function: <f + delta_x, phi> = (f, phi) + phi(x) > So, is find_neighbors() the way to go? No, you're doing something different from my flat plate problem; you shouldn't need to change the mesh topology at all. And find_neighbors() is an internal libMesh function - you shouldn't ever need to worry about it unless it breaks. ;-) --- Roy ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
