Periodic Condition
The Periodic Condition node can be used to define periodicity for the transport between two sets of boundaries. The node prescribes continuity or a specified jump for the transported species and conservation of the flux between the “source” and the “destination” side, respectively. The direction in which the species is transported is dictated by the transport equations in the adjacent domains, and not by the “source” and “destination” names.
Boundary Selection
If the node is activated on more than two boundaries, the feature tries to detect two distinct surfaces, each made up of one or more connected boundaries.
Destination Selection
For more complex geometries, it might be necessary to specify the destination selection manually. To do so, right-click the Periodic Condition node and choose Manual Destination Selection. You can then specify the boundaries that constitute the destination surfaces in the Destination Selection section.
Transported Quantity
Click the checkbox to activate the Periodic Condition for each transported species. Specify the value for the jump of the species concentration between the “source” and “destination” sides. By default there is no jump in concentration, .
Advanced
This setting is only available for deforming or rotating domains, for example when using a Moving Mesh node or a Structural Mechanics interface. From the Frame list, select Reference configuration or Deformed configuration to specify the prescribed value in the reference (material frame) or in the deformed (spatial frame) configuration. They are related by the volume ratio.
Constraint Settings
To display this section, click the Show More Options button () and select Advanced Physics Options in the Show More Options dialog. This section contains settings for specifying the type of constraint and whether to use a pointwise constraint, a weak constraint, or a constraint enforced by Nitsche’s method. See Constraint Settings in the COMSOL Multiphysics Reference Manual for more information.
Orientation of Source
To display this section, click the Show More Options button () and select Advanced Physics Options in the Show More Options dialog. For information about the Orientation of Source section, see Orientation of Source and Destination in the COMSOL Multiphysics Reference Manual.
Orientation of Destination
This section appears if the setting for Transform to intermediate map in the Orientation of Source section is changed from the default value, Automatic, and Advanced Physics Options is selected in the Show More Options dialog. For information about the Orientation of Destination section, see Orientation of Source and Destination in the COMSOL Multiphysics Reference Manual.
Mapping Between Source and Destination
To display this section, click the Show More Options button () and select Advanced Physics Options in the Show More Options dialog. For information about the Mapping Between Source and Destination section, see Mapping Between Source and Destination in the COMSOL Multiphysics Reference Manual.
See the Periodic Condition section in the Equation-Based Modeling chapter in the COMSOL Multiphysics Reference Manual.