Hello, I am trying to implement a formulation for contact mechanics using the FEMSystem. This involves some contributions at the surface being in contact. I add these contributions in FEMSystem::side_time_derivative(bool, DiffContext& c). For this contribution I need the derivatives of the shape-functions in the direction of the surface coordinates, but c.side_fe_var[0]->get_dphi() and _dphidxi(), _dphideta() and _dphidzeta() are even for this boundary FE still related to the orientation of the whole element (HEX8 in my case).
So when looking at a cube c.side_fe_var[0]->get_dphi() gives a different results for e.g. the surface at the button and a surface on the side differ. So how do I get the derivatives of the shape functions in the direction of the two surface coordinates/tangents in a way that is independet of what side of a three dimensional element I am looking at? Regards, Robert ------------------------------------------------------------------------------ Write once. Port to many. Get the SDK and tools to simplify cross-platform app development. Create new or port existing apps to sell to consumers worldwide. Explore the Intel AppUpSM program developer opportunity. appdeveloper.intel.com/join http://p.sf.net/sfu/intel-appdev _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
