"Anurag" wrote in message <email@example.com>... > Hi Guys, I am trying to solve the heat equation in a system with multiple coupled layers, each with its own thermal diffusivity. I cannot find any clear way to specify the boundary conditions here (which is simply flux continuity between the layers). > > Any suggestions would be much appreciated. Thanks! > > Anurag
You didn't specify *how* you are solving this equation. If you are using MATLAB PDE Toolbox, based on the finite element method, no boundary conditions are required on the "internal" boundaries where the coefficient properties (e.g. material properties) change.