In order to account for consumption or production of species in a fracture, the Species Source node adds source terms expressions Si to the right-hand side of the species transport equations.

From the Selection list, choose the boundaries on which to define expressions that govern the source term in the transport equations.

If there are several different parts of the fracture, with subsequent and different sources occurring within them, it might be necessary to remove some boundaries from the selection. The sources in these can then be defined using an additional Species Source node.

Add a source term Si for each of the species solved for. Enter a value or expression in the field of the corresponding species.