square3_TfwNP2v, square3_TfwLP2v, square3_TfwTP2v are model problems for
tangential flow. With Neumann conditions, Lagrange multupliers and
traction elements repectively
square3_TfwNP2v_3diri, square3_TfwLP2v_3diri, square3_TfwTP2v_3diri are
model problems are tangential flow where the tangential flow is imposed
with Neumann conditions, Lagrangian constraints and Traction elements
respectively. The 3diric signifies that we impose dirichlet conditions
on the outflow. This is dangerous.
square3_PowNP2v, square3_PowLP2v and square3_PowTP2v are model problems
for parallel outflow where the parallel outflow boundary is imposed with
Neumann conditions, Lagrangian constraints and Traction elements
respectively.
Variants of parallel outflow, nL meants no lagrange (so imposed by
neumann conditions), wL means the Po boundary is imposed by Lagrangian
constraints.