Subsurface Flow Module Updates


For users of the Subsurface Flow Module, COMSOL Multiphysics® 6.3 offers enhanced capabilities, including simplified mass transfer setup for boundary conditions, improved modeling of relative permeabilities using power law expressions, and a unified approach for defining fluid and porous medium properties. Learn more about these updates below.

Boundary Mass Source Condition

The new Boundary Mass Source boundary condition in the Phase Transport interfaces simplifies the setup of mass transfer due to reactions or other processes on boundaries. It automatically accounts for consumption or production of different phases, and when the Phase Transport in Porous Media interface is coupled with a Darcy’s Law interface, it accounts for the net mass transfer in the flow field. This feature is especially useful when phase transport is linked to surface reactions.

The COMSOL Multiphysics UI showing the Model Builder with the Boundary Mass Source node highlighted, the corresponding Settings window, and a low permeable lens model in the Graphics window.
Multiphase flow over a low permeable lens. The Boundary Mass Source feature is used here for the easy setup of boundary conditions in the Low Permeable Lens tutorial model.

Power Law Option for Relative Permeabilities

The Porous Medium feature in the Phase Transport in Porous Media interface now includes a new Power law option, making it easier to implement relative permeabilities based on power law expressions. This enhancement simplifies the setup and modeling of permeability behavior in porous media simulations.

The COMSOL Multiphysics UI showing the Model Builder with the Fluid node highlighted, the corresponding Settings window, and a 1D plot in the Graphics window.
Relative permeabilities based on power law expressions being used in the two-phase porous medium flow Buckley–Leverett benchmark model.

New Fluid and Porous Medium Nodes in the Phase Transport Interfaces

The Phase Transport interfaces now include two new features: the Fluid and Porous Medium features. The Porous Medium feature includes subfeatures for defining phase and matrix properties, replacing the previous Phase and Transport Properties and Phase and Porous Media Transport Properties features. These updates unify terminology across different physics interfaces, enhancing the user experience. All tutorial models in the Application Library that use one of the Phase Transport interfaces showcase these new features.

The COMSOL Multiphysics UI showing the Model Builder with the Fluid node highlighted, the corresponding Settings window, and a drainage ditch model in the Graphics window.
The new Fluid and Porous Medium features in a model simulating the water table height near a drainage ditch.

Result Templates in the Chemical Species Transport Interfaces

Creating useful and visually appealing plots of reacting systems can be time consuming since there are often many reactants and thus many concentration fields to plot. To save time, there are a number of new Result Templates in the Chemical Species Transport interfaces. Among these, plot array templates are now available that include up to four species concentrations simultaneously in the Graphics window. The Result Templates are available for all Chemical Species Transport interfaces, independent of the add-on product, but are especially useful for the multicomponent transport interfaces included in the modules for chemical engineering as well as in the CFD Module, Porous Media Flow Module, Subsurface Flow Module, and Microfluidics Module.

The COMSOL Multiphysics UI showing the Model Builder with a Surface node highlighted, the corresponding Settings window, plate reactor models in the Graphics window, and the Result Templates window.
The Result Templates window and a plot array of all the concentration fields modeled in the Fine Chemical Production in a Plate Reactor tutorial model.

New Tutorial Application

COMSOL Multiphysics® version 6.3 brings a new example application to the Subsurface Flow Module.