Studies On The Characteristics Of Magnetic Shielding And Transfer Of A Superconducting-Ferromagnetic Metamaterial

With the rapid development of modern electrical science and technology, the control of magnetic field (mainly including magnetic shielding and transmission) has become particularly significant in daily life, devices for industry and military, where static magnetic field is the most common one. Consequently, screening and routing of static magnetic field has caused widespread attention, in virtue of the extensive distribution in space and the properties that the static magnetic quickly decays with distance.Starting from the transformation optics and the design principle of metamaterial, the parameters of medium in transformation space was theoretically designed on the basis of the form invariance of Maxwell equations. According to this principle, a cylinder superconducting-ferromagnetic magnetic shielding shell and magnetic transmission structure were theoretically constructed in virtue of the particular characteristics in these two special materials. In addition, the theoretical foundations of superconducting material was presented for shielding structure and transfer structure.Using the COMSOL multi-physical finite element software, a superconducting-ferromagnetic cylinder structure for magnetic shielding has been investigated for employing the screening of the uniform applied magnetic field created by the Helmholtz coil. These completely different effects of the two materials have been discussed in detail with regard to the distortion caused in the applied magnetic field, and the distortion of these two structures in different wrapping patterns has also been investigated, from which the optimum one was suggested for actual design application. The variation of geometric structure has been studied for achieving the best one which can obtain smallest distortion outside the shielding shell and best shielding effect inside the cylinder.Aiming at the superconducting-ferromagnetic metamaterial transmittal structure, the effect of the number of discrete layers for the transmittal structure has been discussed, from which a two-layer structure was selected for further consideration in the design of magnetic transmittal structure. The transmittal structure has been theoretically designed, based on COMSOL multi-field coupled finite element software, and by adopting the experimental devices, the influence of the geometry on magnetic transmittal structure has been analyzed. Finally, the ferromagnetic material only structure has been compared with the combination one for achieving better transmittal effectiveness. From the simulation and experimental results, it is concluded that the superconducting materials play an important role in the design of the transmittal structure due to its perfect diamagnetism and can greatly increase the transmittal efficiency of magnetic transmission structure.