I am a bit confused by the <material_property> definition block.
With the “media/medium” definition, it is straightforward to define different thermal properties (i.e specific heat and thermal conductivity of the solid component) for different materials with ids defined in the mesh.
With the <porous_media> definition, specific heat and thermal conductivity of the solid are in the fluid block, which is the same for the complete domain (right?).
Similarly, definiton of solid density is completely outside of these and <porous_medium>.
Am I missing something in defining id=x somewhere in the properties?