Dirichlet Boundary Condition

The specifies a value of u on the boundary of the domain: u = r. By default, it is a unidirectional condition, applying reaction terms on u but not on any variables appearing in r.

The Dirichlet boundary condition for each dependent variable (for example, u2), has a corresponding check box (), which is selected by default. Enter a value or expression for the prescribed value in the associated text field or clear the check box as needed. If cleared, no Dirichlet constraint is added for that dependent variable, and, for example, a flux condition on the same boundary then remains as the active boundary condition.

Constraint Settings

To display this section, click the button (

) and select in the dialog box. This section contains settings for specifying the type of constraint and whether to use a pointwise or weak constraint. See Constraint Settings for more information.


	You can add subnodes to exclude the constraint from any surrounding boundary, edge, or point. See Excluded Points, Excluded Edges, Excluded Surfaces.


	See Coefficient Form PDE for all the settings and Compact and Standard Notations for Classical PDEs for the equations that the Classical PDE interface solves.