Spatially Dependent Boundaries

HFSS supports spatially dependent materials, that is, materials whose properties change over their length. Consider a long rectangular sheet object that lies on the XY plane along the Y axis.

To assign Finite Conductivity such that the boundaries are spatially dependent follow these steps:

1. Select the line as shown in the figure below.

   

2. Right-click anywhere in the modeler and select Assign Boundary > Finite Conductivity as shown below.

   

   This causes the Finite Conductivity Boundary dialog box to appear as shown below.

3. Type the expression in the Conductivity field to include the spatially dependent material properties of the sheets. For example, in this design, the Conductivity field has the following expression: $sigma0*(1.0 + $beta*abs(y)), where $sigma and $beta are the predefined project variables and y specifies the local y co-ordinate associated with the sheet.

   

   Note: Whatever model units you define, specify the expression in the Conductivity field in SI units. To verify the Coordinate System associated with the sheet, double-click the Create Rectangle command associated with the object from the History Tree to open the Attribute window as shown below.

   

   Note: The spatial dependency can only be expressed in Cartesian coordinates.