Simplify
The simplify tool removes redundant regions, faces and edges.
Dielectric boundary faces are redundant if they have the same medium (for example, metal, free space, dielectric) on both sides. When a face separating an internal free space region from the outside free space is deleted, the internal region is merged with the outside. Since the outside medium is free space, faces can only be removed from closed regions if the internal medium is set to free space.
Edges are not redundant if the face normal on either side of the edge are in opposite directions.
The simplify operation results in the model being electromagnetically the same as the
original, but may not have the same meshing constraints. For example, if an imprinted
point is removed, a mesh vertex cannot be guaranteed at this location. Faces cannot be
deleted unless the regions they separate can be merged. The same applies to edges on
face boundaries and geometry points at the ends of edges.