Modeling Electromagnetic Losses
In general, AC/DC interfaces compute electromagnetic losses by default. The volumetric loss density is made available as a global scalar variable with name <name>.Qh, where <name> is the Name of the physics interface. Depending on the interface and study type, the expression for computing electromagnetic losses can be different. Typical application scenarios and modeling approaches are:
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Use the The Joule Heating Interface () to model resistive heating and heating due to dielectric losses. This multiphysics interface adds an Electric Currents interface and a Heat Transfer in Solids interface. The multiphysics couplings add the electromagnetic power dissipation as a heat source, and the electromagnetic material properties can depend on the temperature. Different dielectric and conduction models are available in the Electric Currents interface.
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Use the The Induction Heating Interface () to model induction and eddy current heating. This multiphysics interface is based on the assumption that the magnetic cycle time is short compared to the thermal time scale (adiabatic assumption). Use this interface together with preset study types such as Frequency-Transient to model a variety of electromagnetic heating problems.
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Use the Loss Calculation subfeature under the Ampère’s Law or domain Coil or Faraday’s Law or Magnetic Flux Conservation feature to compute the copper loss due to the resistive heating or the iron loss due to the Hysteresis, eddy current and other effects. The feature is available with both Time Dependent and Frequency Domain studies. For Time Dependent studies, the loss calculation has to be used in combination with the Time to Frequency Losses study step.