Flux Links to/from Network Pathways

The only way to transport mass out of a Network pathway is by specifying an advective mass flux link to another pathway. For Network pathways, the flowing medium is always the Reference Fluid. Diffusive mass flux links from Network pathways (diffusive outfluxes) and special purpose (direct transfer, precipitate removal and treatment) mass flux links from Network pathways cannot be created.

Note that the flow rate of the fluid defined in an advective mass flux link from a Network pathway, if used at all, is only used to determine how mass from a single sink is apportioned between Outflow flux links.

That is, the mass flux link is used only to specify where the mass is to be discharged. The pipe flow rates within the fracture network determine how mass moves through the pathway and the rate at which mass is discharged. Because the flow rates in the mass flux links to/from Network pathways do not impact the manner in which mass is transported, GoldSim does not test to ensure that the flows in the flux links to and from the pathway are consistent with the internal flows in the network pipes.

You can transport mass into a Network pathway via an advective mass flux link from any other type of pathway and/or via a diffusive mass flux link from a Cell pathway. Within GoldSim, the concentration and diffusive length on the Network pathway side of a diffusive mass flux link are assumed to be zero. Hence, like advective mass flux links, diffusive mass flux links involving Network pathways are uni-directional.

Warning: GoldSim does not enforce a balance for the flow of the Reference Fluid in a Network pathway. That is, the Inflows into the pathway do not need to be equal to the Outflows from the pathway. Unlike Cells and Pipes, however, if the specified Outflows are less than the specified Inflows, it does not imply that the species concentrations leaving the Network pathway would be greater than those entering the pathway. This is because not all of the mass than enters a Network pathway necessarily must exit the pathway, since you may choose to ignore some sinks (e.g., those that discharge to deep locations and effectively leave the system).