Mass of Water for Reactive Transport Model

[mcossio23]

Hello,

I have a question pertaining the definition of the mass of water for a reactive transport model. I am trying to simulate a waste rock dump that is ~ 100 m tall with a 100 cells; therefore, each cell is 1 m. Assuming a 1 D approach (1 m2); then each cell is 1 m3. Assuming a volumetric water content of 0.007 throughout the whole column, assuming full saturation, each cell should be able to hold ~ 7 L (assuming a water density of 1,000 L/kg).

My question here is: Whenever a volume of material is not know, a mass of water is typically assumed to 1 L; however, in the instance where material properties are know (as my example above), then each cell would need to account for the true water mass that such material will be in contact. is it then correct to assign a 7 kg water mass for each of the cells?

Any help with this would be greatly appreciated!
Manny

[dlparkhurst]

With TRANSPORT, every cell is assigned the same volume of water. Even if you initially assign different volumes of water, after one pore volume, the volume of SOLUTION 0 will have been transported to each cell.

It is simplest to assign 1 kgw (approximately 1 L) to each cell. The definition of SOLUTION will by default have 1 kg of water. You would then assign to each cell the moles of other reactants that are appropriate for 1 L of water.

That does not mean the lengths of the cells must be the same. Because the time step is fixed, the velocity of water through each cell is determined by its length. If you want the same velocity in all cells of the column, then all cells should be defined with the same length.