Porous Medium
Use this node to model the concentration of diluted species transported by a solvent (mobile fluid phase) through interstices in a solid porous medium. In addition to transport due to convection and diffusion, the node contains functionality to include species evolution through adsorption and dispersion.
This feature is only available in a limited set of add-on products. See https://www.comsol.com/products/specifications/ for more details on availability.
Species transport through a porous medium is affected both by properties of the fluid phase, and as well as properties of the solid matrix. These properties are defined in the Fluid and Porous Matrix subnodes respectively. The Porous Medium node supports material properties using a Porous Material node (described in the COMSOL Multiphysics Reference Manual), where properties are defined per phase in a similar manner.
Add an Adsorption or a Dispersion subfeature to the Porous Medium to account for the corresponding transport mechanism.