Assigning a Dependent Boundary for a 3D AC Conduction Solver

Assigning a dependent boundary is the second step in creating matching boundaries. The field on the Independent boundary is mapped to the dependent boundary.

Note: You must define an Independent boundary before creating the dependent boundaries that are associated with it. Assign dependent boundaries only to the outer surfaces of the problem region.

To set a dependent boundary:

  1. Select the section of the geometry on which you want to apply the boundary condition (typically a face).

  2. Click Maxwell 3D > Boundaries > Assign > Matching > Dependent.

    The Dependent Boundary window appears.

  3. Enter a name for the boundary in the Name box, or accept the default.
  4. Select the independent boundary to which the dependent is to be assigned from the Independent drop-down menu.
  5. To specify the coordinate system, do the following in the Coordinate System section:
    6. Note: You must specify the coordinate system in the plane on which the boundary exists. First draw the U vector of the coordinate system. Maxwell uses the U vector you draw and the normal vector of the boundary face to calculate the v-axis. Then specify the direction of the V vector.
    1. Select New Vector from the U Vector drop-down menu.
      The Create Line message appears asking you to draw the U vector of the coordinate system in the plane of the selected face, and the Dependent Boundary dialog box disappears while you draw the U vector.

    2. Select the U vector's origin in one of the following ways:

      Note: The U vector's origin must be on the boundary's surface.
      • Click the point.
      • Type the point's coordinates in the in the X, Y, and Z boxes.
    3. Select a point on the u-axis in the same way.
      When the second point is identified, the vector is set, and the Dependent Boundary window reappears, with Defined listed in the U Vector drop-down menu.
    4. To specify the direction of the V vector, select or clear the Reverse Direction check box.
  6. In the Relation section, select one of the following to specify the field behavior on the boundary:

    Edep = Eind

    Click this radio button if the dependent and independent boundaries have the same magnitude and direction.

    Edep = -Eind

    Click this radio button if the dependent boundary field has the same magnitude as but the opposite direction from the independent boundary field.


  7. Optionally, click Use Defaults to revert to the default values in the window.
  8. Click OK to assign the boundary to the selected object.
Note: The origin must be a vertex point of one of the objects.