Flux
This node may be added as a subnode to any species node. See also Common Settings for the Species Nodes in the Electrophoretic Transport Interface.
This node can be used to specify the species inward flux across a boundary. The flux can represent a flux from or into a much larger surrounding environment, a phase change, or a flux due to chemical reactions.
Inward Flux
Enter a value or expression for the species mass flux J0. Use a minus sign when specifying a flux directed out of the system.
External convection
Set Flux type to External convection to prescribe a flux to or from an exterior domain (not modeled) assumed to include convection. The exterior can for example include a forced convection to control the temperature or to increase the mass transport. In this case the prescribed mass flux corresponds to
where kc is a mass transfer coefficient and cb is the bulk concentration, the typical concentration far into the surrounding exterior domain.