On Tue, Jan 15, 2008 at 08:33:07AM +0100, Murtazo Nazarov wrote: > > Related question for both incompressible flow and elasticity > > problems. Suppose I have a plane of symmetry that will allow me to > > reduce my computational domain. If > > > > \sigma_ij > > > > is the relevant stress tensor, then I will have that > > > > t^k_i \sigma_ij n_j = 0 > > Ones you have tangential and normal vectors, you can include this as a > boundary term to the ffc form?
FFC/DOLFIN only have built-in facet normals (FacetNormal). There is no FacetTangent but it would be easy to add (if we just define what we mean by the tangents on a face of a tetrahedron). -- Anders > > > > where t^k is the k-th tangential vector of the local geometry. > > Physically, this is vanishing shear stress. This is in addition to > > the condition > > > > u_i n_i = 0 > > > > for no normal flow (the slip condition). > > > > Any thoughts on implementing the vanishing shear stress condition? > > > > -gideon > > > > On Jan 14, 2008, at 2:57 PM, Murtazo Nazarov wrote: > > > >>> Is there an obvious high level way to implement normal flow type > >>> boundary conditions or symmetry type boundary conditions? > >>> > >>> -gideon > >>> > >> > >> If you mean slip boundary condition which for normal velocity, it is > >> already implemented and soon will be available with UNICORN. > >> > >> The slip with friction is also implemented. > >> > >> /murtazo > >> > >>> _______________________________________________ > >>> DOLFIN-dev mailing list > >>> [email protected] > >>> http://www.fenics.org/mailman/listinfo/dolfin-dev > >>> > >> > >> > > > > _______________________________________________ > > DOLFIN-dev mailing list > > [email protected] > > http://www.fenics.org/mailman/listinfo/dolfin-dev > > > > > _______________________________________________ > DOLFIN-dev mailing list > [email protected] > http://www.fenics.org/mailman/listinfo/dolfin-dev _______________________________________________ DOLFIN-dev mailing list [email protected] http://www.fenics.org/mailman/listinfo/dolfin-dev
