Analysis of the wave process in the laminated core of the pulsed magnetic devices

In the assumption that equivalent parameters of the laminated core medium (as magnetic permeability μ, dielectric constant ε and electrical conductivity σ) are known in result of medium homogenization the comparative role of diffusion and wave propagation of the pulsed magnetic field in the core has been investigated in the work. The equation of magnetic field has been considered in the non-dimensional form with two main criteria of similarity: magnetic Reynolds´ number Re_m and wave parameter K_w. The wave process in the cross section of core has been simulated numerically in the package Comsol at the sudden switching on the field at the border of cross section. The resulting field distribution in time and space are sensitive not only to meaning of each parameter Re_m or K_w but also to their ratio β = K_w / Re_m = ε /(σT), where T is a pulse duration. It was shown that for β > 0.01 a role of the wave process becomes more significant and at β = 1 the wave process is prevailing over diffusion process. At opposite case, when β <;0.01, the medium of core losts the wave properties. Both modes of process are presented at the time pictures of the field distribution in the cross section of core.