Selecting any of these interfaces under the Chemical Species Transport > Reacting Flow or Chemical Species Transport > Reacting Flow in Porous Media branches of the Model Wizard or Add Physics windows, adds a fluid flow interface and either a Transport of Diluted Species or Transport of Concentrated Species interface to the Model Builder.

In addition, the Multiphysics node Reacting Flow is added. The Reacting Flow node predefines and controls the couplings between the mass and fluid transport in order to facilitate easy set up of models.