Improvement of magnetic shielding properties of hollow cylindrical high temperature superconductors using the finite element method

In this thesis, we have investigated the magnetic shielding properties of a bulk tube-shaped high temperature superconductor (HTS). In the first stage, we have analyzed temperature dependence of shielding factor (SF). It has been calculated that the HTS tube is able to make shielding up to applied magnetic flux density value of Ba = 0.5 T at T = 10 K. In the second stage, the influence of magnetic field's sweep rate (dBa /dt) on the magnetic shielding was numerically examined. It has been reported that the maximum value of magnetic shielding limit Blim = 20.8 mT at dBa/dt = 30 μT/s. In the third stage, using the certain lines over the superconducting tube, we have worked out the shielding magnetic flux density (Bsz) of the HTS tube. In the final stage, we have studied the magnetic shielding properties of hybrid ferromagnetic/superconductor (F/S) configurations consisting of two coaxial cylinders, with one of each material. We have investigated and compared the penetration of a uniform axial applied magnetic flux density in two cases (ferro-in, ferro-out). In both cases, we assess how the ferromagnetic tube improves the magnetic shielding properties of the sole HTS tube. The effects of the geometrical parameters of the ferromagnetic tube have also been studied. While the increase in the calculated shielding limit for the Ferro-in configuration is ∼ 35%, this value is around ∼ 300% for the Ferro-out configuration.