[Libmesh-users] Quadrature rule for unit normals at centroids, edges, and nodes

[Nishant N. <nis...@gm...>]

Hi Folks,

I am working on an application where I need the unit normals on all the
nodes, the centroid, and (in 3D) on the edges halfway between the nodes of
a surface mesh. The boilerplate code I am using to get the normals is
something like:

libMesh::UniquePtr<FEBase> fe_bdry(FEBase::build(dim, fe_type));
libMesh::UniquePtr<QBase> qrule_bdry(fe_type.default_quadrature_rule(dim -
1));
fe_bdry->attach_quadrature_rule(qrule_bdry.get());

...

const std::vector<libMesh::Point>& bdry_normals = fe_bdry->get_normals();

When constructing the QBase, is there a quadrature rule and order I can
pass to get the normals at those specific locations? My surface meshes will
always consist of EDGE2 elements in 2D and TRI3 elements in 3D.

Thanks!
Nishant

*Nishant Nangia*
Northwestern University
Ph.D. Candidate | Engineering Sciences and Applied Mathematics
Tech L386