I am wondering what is the best way to model magnetic and electric field shielding from a magnetic dipole in the near field?
For example, let's say you have a coil of current carrying wire in the x-y plane which creates an AC magnetic field along the z-axis. I am interested in a model in which I could put in material parameters (such as $\sigma$, $\epsilon$, $\mu$) for a shielding plate located distance $r$ from the source.
I tried using section 5.4 of an online electromagnetic book which talks about reflection, and transmission of of EM waves. I would estimate wave impedance as $Z=\omega\mu_0r$ which is the equation for near field magnetic source. I determine the intrinsic impedance of the shielding material as $\eta=\sqrt {\frac {j\omega\mu} {\sigma + j\omega\epsilon}}$. I want to try good conductors as well as ferrite so I'm not making any assumptions such as good conductor or loss-less medium.
I implemented this but the result was not what I expected. I would expect highest energy reflection with the ferrite because it has low reluctance to magnetic fields and would guide the flux through it and return to source. However, a good conductor (e.g aluminum) had almost 100% energy reflection, but I was expecting the shielding mechanism of conductors would be all energy lost as absorption from eddy currents.
Let me know your thoughts of whether this is a legit model; I can give more info about parameters/equations used if that's helpful.