Question A conductor is to be passed through a wall (via a wall bushing). We are trying to calculate the eddy currents set up in the iron reinforcing surrounding the cable.Is there any way that HIFREQ could be used to calculate these eddy currents?
Answer The computational model in HIFREQ does not account for the propagation and attenuation of the magnetic field inside magnetic materials (such as steel). As such, it can't be used to compute accurately the distribution of induced currents inside such a magnetic material. If the problem you are attempting to model involves steel plates, then you could only get a rough approximation of the magnitude of the effect using HIFREQ.
On the other hand, if the reinforcing material consists of a mesh of steel wires, then HIFREQ can compute the induced current in those wires very accurately, especially when the expected magnitude of the currents is small. This last condition helps, because in that case the variation of the permeability of the steel with respect to the magnitude of the current flowing into it can be neglected, and an average value (~300) can be used.