Defining SURFACES and EQUILIBRIUM_PHASES in TRANSPORT with a stagnant zone

[dvlassopoulos]

I am interested in simulating solute retardation due to adsorption in a dual porosity medium (e.g. in fractures vs matrix). Is it possible to define different SURFACE site densities, EXCHANGE sites, and/or EQUILIBRIUM_PHASES for the mobile cells and immobile cells in a transport simulation?

[dlparkhurst]

All cells are identified by index numbers: 1 to n for mobile, n+2 to 2n + 2 for first immobile, etc. You can put any reactant definition in a cell by using the appropriate number. So, yes, define SURFACE 1 for cell 1 and SURFACE n + 2 for the immobile cell next to cell 1. (I think I have the numbering right, but you can check).

[dvlassopoulos]

Many thanks for the quick reply, David. It wasn't entirely clear to me but makes sense. Dimitri