Sometimes you need to model the concentration of a gas in a liquid or a gas-permeable solid. You can work out simple models by hand using mass transport principles, but more complicated models require finite element software. Unfortunately COMSOL is ignorant of Henry’s law, but you can bring it up to speed through the clever use of boundary conditions.
This blog post contains information about the web site. It’s mostly for my reference, but since I benefited from countless online resources while wrestling with the configuration, I thought I would post it to return the favor.