Roy, 1st as always thanks for the quick response.
I see what you mean. And no I didn't I did the gradient calculation in VisIt. I don't use/calculate this gradient in my code. Here is the reason I suspected gradients: the problem I'm solving is complicated but in short what I solve for is a fracture mechanics problem and the solution I showed you is one step of an iterative solution for the displacement field; long story short when I have a discontinuity of gradient of displacement (i.e. a kink in the displacement field) that will initiate cracks. In this case when the gradient is not continuous along mesh partitions I get fracture along mesh partitions. I'll try to run some more checks and then get back to you before spending time on a test case. Ata On Dec 4, 2012, at 2:04 PM, Roy Stogner <royst...@ices.utexas.edu> wrote: > > On Tue, 4 Dec 2012, Roy Stogner wrote: > >> On Tue, 4 Dec 2012, Ataollah Mesgarnejad wrote: >> >>> I found a potential bug with Clough elements. I'm solving a 4th order >>> problem using C1 Clough elements and when I plot magnitude of gradient of >>> the solution I found out that it is discontinuous on mesh partition >>> boundaries. I would appreciate if any comments. >> >> Can you put together a test case reproducing the problem? > > Actually, before you do that: are you sure you localized the solution > before using it to calculate the gradients? That's the only way I > could picture encountering a partitioning-specific gradient > discontinuity in C1 elements - the gradient components aren't > calculated (and thus aren't potentially miscalculated) from some other > degrees of freedom, they *are* degrees of freedom. > --- > Roy ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Libmesh-users mailing list Libmesh-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-users
