Like all COMSOL modules, the interfaces described in this guide include all the steps available for the modeling process, which are described in detail in the COMSOL Multiphysics User’s Guide and the COMSOL Multiphysics Reference Guide:

-Definitions of parameters and model variables

-Creating, importing and manipulating geometry

-Specifying the fluid-flow, and material and heat transport material properties

-Defining the reaction formulas and physics in the system and on boundaries, and coupling them to other physics

-Meshing a modeling domain with appropriate consideration given to the reaction system’s behavior

-Solving the equations that describe a system for stationary or dynamic behavior, or as a parametric or optimization study

-Collecting and analyzing results to present for further use in other analyses.

Once a model is defined, you can go back and make changes in all of the branches listed, while maintaining consistency in the other definitions throughout. You can restart the solver, for example, using the existing solution as an initial guess or even alter the geometry, while the equations and boundary conditions are kept consistent through the associative geometry feature.

Model Builder Options for Physics Feature Node Settings Windows

There are several features available on many physics interfaces or individual nodes. This section has a short overview of the options and includes links to the COMSOL Multiphysics User’s Guide where additional information is available.

This information is also searchable from the COMSOL Multiphysics

software Help menu.

Tip

S H O W M O R E O P T I O N S F O R P H Y S I C S I N T E R F A C E S A N D F E A T U R E N O D E S

To display additional features for the physics interfaces and feature nodes, click the

Show button () on the Model Builder and then select the applicable option.

After clicking the Show button (), some sections display on the Settings window when a node is clicked and other features are available from the context menu when a node is right-clicked. For each physics interface, the additional sections that can be

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displayed included Equation, Advanced Settings, Discretization, Consistent Stabilization, and Inconsistent Stabilization.

You can also click the Expand Sections button () in the Model Builder to always show some sections or click the Show button () and select Reset to Default to reset to display only the Equation and Override and Contribution sections.

For most physics feature nodes, both the Equation and Override and Contribution sections are always available. Click the Show button () and then select Equation View to display the Equation View node under all physics interface nodes in the Model Builder.

Availability of each feature, and whether it is described for a particular interface or node, is based on the individual physics interface and feature node. For example, the

Discretization, Advanced Settings, Consistent Stabilization, and Inconsistent Stabilization sections are often described individually throughout the documentation as there are unique settings.

In the COMSOL Multiphysics User’s Guide:

• Showing and Expanding Advanced Feature Nodes and Sections

See Also

• The Model Builder Window

P A I R S E L E C T I O N

When a feature is selected from the Pairs submenu, an identity pair may have to be created first. Details about this node are found in the following links.

In the COMSOL Multiphysics User’s Guide:

• Identity and Contact Pairs

See Also

• Specifying Boundary Conditions for Identity Pairs

C O N S I S T E N T A N D I N C O N S I S T E N T S T A B I L I Z A T I O N

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