Plane Symmetry
The Plane Symmetry node is obsolete and will be removed in future versions. Instead, consider using the Symmetry node, which is capable of handling sector symmetry as well as plane symmetry with multiple perpendicular reflection planes. The Plane Symmetry and Symmetry features should not be used together in the same model.
Use the Plane Symmetry node to specify boundaries which correspond to symmetry; that is, boundaries where the incoming and outgoing fluxes are equal. Note that these boundaries must be planar and cannot be curved.