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تسجيل مستخدم جديدElectromagnetic coupling of twisted multi-filament superconducting tapes in a ramped magnetic field
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We investigate theoretically the magnetization loss and electromagnetic coupling of twisted multi-filament superconducting (SC) tapes in a ramped magnetic field. Based on the two-dimensional reduced Faraday--Maxwell equation for a tape surface obtained with a thin-sheet approximation, we simulate numerically the power loss $P$ per unit length on twisted multi-filament tapes in the steady state. The current density profile clearly shows electromagnetic coupling between the SC filaments upon increasing the field sweep rate $beta$. Although the $beta$ dependence of $P/beta$ for twisted multi-filament SC tapes closely resembles that for filaments in an alternating field, we show that the mechanism for electromagnetic coupling in a ramped field differs from that in an alternating field. We also identify the conditions under which electromagnetic coupling is suppressed for the typical sweep rate of a magnet used for magnetic resonance imaging.
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Magnetization loss on a twisted superconducting (SC) tape in a ramped magnetic field is theoretically investigated through the use of a power law for the electric field--current density characteristics and a sheet current approximation. First, the Ma
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