A Study on the Drag Force According to the Material Properties of Steel Tube Caused by Ultra-High-Speed Superconducting Magnets Using Jiles-Atherton Modeling

Abstract

This paper is about electromagnetic drag in a superconducting magnet-based ultra-high-speed vacuum tube train system capable of reaching speeds of 1200 km/h. The vacuum tube of the tube train system must be constructed using steel with robust structural properties to maintain a vacuum state of 0.001 atm. Because the steel tube is an electrically conductive and magnetic material, it generates an electromagnetic drag force as the superconducting magnets mounted on the train move. Therefore, we examined how the characteristic of this electromagnetic drag force changes depending on the material properties of the steel tube, specifically their conductivity and permeability. For the conductivity of the steel tube, it was confirmed that as the value increases, the speed at which maximum drag occurs shifts to the low-speed region. For the permeability of the steel tube, since it exhibits nonlinear characteristics depending on the magnetic field distribution caused by the superconducting magnet, we utilized the Jiles-Atherton Modeling to generate virtual steel properties based on the hysteresis curve of AISI 1010 steel and analyzed their characteristics. As a result, it was confirmed that the higher the saturation permeability in the saturation region-that is, the higher the saturation flux density of the steel-the greater the reduction in electromagnetic drag force due to the movement of the superconducting magnet.