Unsaturated 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.
Use this node to model the concentration of diluted species transported by a liquid (mobile fluid phase) in a partially filled solid porous medium. The interstices of the porous medium contains the liquid carrier phase and gas pockets. Apart from convection and diffusion, the node contains functionality to include species evolution through adsorption, dispersion, and volatilization.
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.
The properties of each phase present are defined using the Liquid, the Gas, and the Porous Matrix subnodes respectively. The Unsaturated 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 Unsaturated Porous Medium to account for the corresponding transport mechanism.