Discussion Forum

Hi, recently i was analysing the waveguide mode using RF module in COMSOL. The waveguide was circular metallic waveguides. Theoretically for ideal smooth metal surface, the mode transmission loss is very low. But as one could know, the surface roughness of the metal along the propagation direction will cause significant loss. ** **My question is, how to include this loss during the mode analysis? The surface roughness in the TBC (transition boundary condition) defines the roughness in the axial direction, instead of along the propagation direction. Thank you.