BC_Type = SymmetryBC: This boundary condition is used at the symmetry surfaces. HyperXtrude imposes zero normal velocity at these planes.
Syntax for this boundary condition is:
SymmetryBC Boundary_Name { }
If the elements on this BC lie on a single plane and you know the components of the normal in x, y, and z, you can specify this value.
SymmetryBC Boundary_Name {
Nx = component of normal in x direction
Ny = component of normal in y direction
Nz = component of normal in z direction
}
For example, if the face is in yz plane and the boundary is called sym_yz then
SymmetryBC sym_yz {
Nx = 1.0
Ny = 0.0
Nz = 0.0
}