COMSOL Multiphysics^® 6.3 Release Highlights

Porous Media Flow Module Updates

For users of the Porous Media Flow Module, COMSOL Multiphysics^® version 6.3 introduces a nonequilibrium formulation for moisture transport in porous media, a new feature that accounts for consumption or production of different phases due to reactions or other physical processes at a boundary, and an app to compute porosity and permeability for various unit cell configurations. Read more about these updates below.

Moisture Transport in Porous Media

The nonequilibrium formulation for moisture transport in porous media can now be used to solve both relative humidity and liquid water saturation, extending the modeling applicability beyond equilibrium assumptions. This new functionality is available in the Hygroscopic Porous Medium feature.

Two new moisture transport interfaces are available in the Model Wizard. The first interface, Nonequilibrium Moisture Transport in Porous Media, computes both relative humidity and liquid water saturation in porous media without assuming vapor–liquid equilibrium. The second interface, Moisture Transport in Free and Porous Media, is parameterized to simplify the setup of models involving multiple coexisting media. A new Porous Interface feature also offers flexible modeling between various media, such as evaporation at interfaces. The new Superheated Steam Drying tutorial model showcases the Moisture Transport in Free and Porous Media interface and Porous Interface feature.

The COMSOL Multiphysics UI showing the Model Builder with the Hygroscopic Porous Medium node highlighted, the corresponding Settings window, and a wood particle model in the Graphics window.

The settings for the Hygroscopic Porous Medium feature with the new nonequilibrium formulation selected.

New Functionality in the Phase Transport Interfaces

A new Boundary Mass Source boundary condition has been added to the Phase Transport interfaces. This new feature accounts for the consumption or production of different phases due to reactions or other physical processes at boundaries. Boundary conditions will now be easier to set up when, for example, phase transport is coupled to surface reactions. Additionally, to help unify nomenclature across the different physics interfaces, the new Fluid and Porous Medium nodes have replaced the previously available Phase and Transport Properties and Phase and Porous Media Transport Properties nodes in the Phase Transport interfaces.

The COMSOL Multiphysics UI showing the Model Builder with the Boundary Mass Source highlighted, the corresponding Settings window, and two Graphics windows.

The Boundary Mass Source feature used to model reactions at the gas diffusion electrodes in a fuel cell. The model also uses the new Fluid and Porous Medium nodes.

Power Law Option for Relative Permeabilities

The Porous Medium feature in Phase Transport in Porous Media 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.

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 Models

COMSOL Multiphysics^® version 6.3 brings a new tutorial model and app to the Porous Media Flow Module.

Superheated Steam Drying of a Wood Particle

A wood particle model showing the temperature.

Wood particle dried by superheated steam with the new nonequilibrium formulation.

Application Library Title:
superheated_steam_drying
Download from the Application Gallery

Homogenized Porous Material Properties App

An app of a homogenized porous material model showing the velocity magnitude in the Graphics window.

Use this app to compute porosity and permeability for various unit cell configurations and export the results as a porous material for large-scale simulations.

Application Library Title:
homogenized_porous_material_properties
Download from the Application Gallery

COMSOL Multiphysics® 6.3 Release Highlights