Magnetic field concentration: comparison between several shapes of superconducting shields

This paper deals with a system of flux density concentration using superconducting shields. The development of single grain high, temperature superconductors allows the conception of large sized magnetic shields. These shields force the flux density to be concentrated by modifying its spatial distribution. The authors' system consists of two low field solenoids, which have the same arrangement as Helmoltz coils. Between these two coils, two superconducting plates are arranged on both sides of the axis. For this study, the superconductor is considered as perfect. They propose to discuss the efficiency of several concentrating devices. To make their study, they performed a 3D-field calculation tool using a Monte-Carlo method. The main advantage of this method is a very simple algorithm to compute, even if the geometry is complicated. The authors have shown that if the distance between the two plates is small enough in respect to the coils diameter, the flux density is much higher than the one inside the coils. They also show the influence of the shape of the shields in the guidance of the flux lines. They have validated their simulations with an experiment.