The External Current Density node adds an externally generated current density
Je, which appears in Ohm’s law
The external current density does not contribute to the losses (due to Joule heating), since there is no electric field associated with it. To include the contribution to the losses from the external current density, select the Add contribution of the external current density to the losses check box. Then select an option from the
External losses list —
From domain conductivity (the default) or
User defined. If
From domain conductivity is selected, the heat source is computed using the conductivity specified in the material model feature (such as
Current Conservation) that is applied in the domain. For
User defined, enter a value for
Qe (SI unit: W/m
3) to specify a user-defined heat source.
Add a contribution as a Harmonic Perturbation by right-clicking the parent node or clicking
Harmonic Perturbation on the
Physics toolbar. For more information see
Harmonic Perturbation — Exclusive and Contributing Nodes in the
COMSOL Multiphysics Reference Manual.
Based on space dimension, enter the coordinates (x,
y, and
z for 3D components, for example) of the
External current density Je (SI unit: A/m
2). The defaults are 0 A/m
2.
