17.6.2.28.1. Magnetic Flux Boundary Conditions

Available for 3D simulations only.

Magnetic flux boundary conditions impose constraints on the direction of the magnetic flux on a model boundary. This boundary condition may only be applied to faces. By default, this feature constrains the flux to be normal to all exterior faces.

Selecting Flux Parallel forces the magnetic flux in a model to flow parallel to the selected face. In the figure below, the arrows indicate the direction of the magnetic flux. It can be seen that the flux flows parallel to the xy plane (for any z coordinate).

A flux parallel condition is required on at least one face of the simulation model. It is typically applied on the outer faces of the air body to contain the magnetic flux inside the simulation domain or on symmetry plane faces where the flux is known to flow parallel to the face.

To set this feature, right-click the Magnetostatic environment item in the tree and select Magnetic Flux Parallel from the Insert context menu or click the Magnetic Flux Parallel option on the Context tab. It can only be applied to geometry faces and Named Selections (faces).

Half-symmetry model of a keepered magnet system. Note that the XY-plane is a Flux Parallel boundary. The flux arrows flow parallel to the plane.

Half-symmetry model of a keepered magnet system. Note that the YZ-plane is a Flux Normal boundary. The flux arrows flow normal to the plane. This is a natural boundary condition and requires no specification.


Note:  Applying the flux parallel boundary conditions to the exterior faces of the air domain may artificially capture more flux in the simulation domain than what physically occurs. This is because the simulation model truncates the open air domain. To minimize the effect, ensure the air domain extends far enough away from the physical structure. Alternatively, the exterior faces of the air domain may be left with an unspecified face boundary condition. An unspecified exposed exterior face imposes a condition whereby the flux flows normal to the face. Keep in mind that at least one face in the model must have a flux parallel boundary condition.