Multilayer theory of d.c. linear brakes with solid-iron secondary

The paper proposes a new theory for d.c. linear brakes with solid-iron secondary. Such brakes may be used to supplement the action of standard braking systems on conventional trains. The theory is based on 2-dimensional Fourier-series decomposition of the primary m.m.f., while the solid-iron secondary is notionally split into thin sheets of constant permeability, determined by an underrelaxed iterative procedure. The theoretical and test plots of braking force against speed show a fairly good agreement.