Domain, Boundary, Point, and Pair Nodes for the Magnetic Fields, No Currents Interface
The Magnetic Fields, No Currents Interface has these domain, boundary, point, and pair nodes available from the Physics ribbon toolbar (Windows users), Physics context menu (Mac or Linux users), or right-click to access the context menu (all users).
In general, to add a node, go to the Physics toolbar, no matter what operating system you are using. Subnodes are available by clicking the parent node and selecting it from the Attributes menu.
To obtain a unique solution, the value of the magnetic potential must be provided at least at one point. If the magnetic insulation boundary condition is used everywhere, the potential has to be fixed using a point condition.
About the Boundary Conditions
In magnetostatics the relevant physics interface condition between two domains 1 and 2 is
This condition provides continuity of the normal component of the magnetic flux density and is automatically satisfied by the natural boundary condition for interior boundaries, which is
Available Nodes
These nodes are available for this physics interface and listed in alphabetical order. Also see Table 5-3 for a list of interior and exterior boundary conditions.
•
External Magnetic Flux Density
•
Initial Values
•
Force Calculation1
•
Magnetic Flux Conservation
•
Magnetic Flux Density
•
Magnetic Insulation
•
Magnetic Scalar Potential
•
Magnetic Shielding
•
Periodic Condition
•
Sector Symmetry1
•
Thin Low Permeability Gap
•
Zero Magnetic Scalar Potential
1 Described for another physics interface in this user guide.
•
Infinite Elements, Perfectly Matched Layers, and Absorbing Layers in the COMSOL Multiphysics Reference Manual
Table 5-1 lists the interior and exterior boundaries available with this physics interface.
Table 5-3: Interior and Exterior Boundary Conditions for the Magnetic Fields, no Currents Interface
Physics Node
Interior
Exterior
External Magnetic Flux Density
 
x
Magnetic Flux Density
 
x
Magnetic Insulation
x
x
Magnetic Potential
 
x
Magnetic Shielding
x
x
Periodic Condition
 
x
Thin Low Permeability Gap
x
 
Zero Magnetic Scalar Potential
 
x