Mechanical effects: challenges for high-field superconducting magnets

Abstract

Due to its clean products and sufficient raw materials, fusion energy is expected to become one of the main solutions of the energy crisis and ensuring the sustainable development of human society, which is a long-term strategic frontier field. The promise of fusion energy is to constrain the motion of high-temperature plasma by the high magnetic field generated by superconducting magnets, and then achieve controllable thermonuclear fusion. Fusion power is proportional to the fourth power of the magnetic field strength. Thus, future commercial fusion reactors need a higher magnetic field as the basis for sustainable development [1]. In order to verify the scientific and technological feasibility of fusion energy, China, the United States, the European Union, Russia et al. have jointly participated in the construction of the International Thermonuclear Fusion Test Reactor (ITER), which is expected to produce the first plasma discharge by 2025 [2]. Currently, China is leading the world in many fields of fusion energy research. For example, the experimental advanced superconducting Tokamak (EAST) whole-superconducting Tokamak located at the Institute of Plasma Physics in the Chinese Academy of Sciences has achieved a repeatable world record of stable plasma operation at 120 million degrees Celsius for 101 seconds, which provides a solid foundation for ITER and also China's future Independent Building Fusion Reactor (https://www.cas.cn/syky/202105/t20210528_4790357.shtml). Prof. Jiangang Li, an academician of the Chinese Academy of Engineering, participated in and completed the design and construction of EAST plasma facing componments (PFCs) engineering by the support of the national ‘9th five-year plan’ major scientific and technological infrastructure, and presided over the completion of the national ‘11th five-year plan’ major scientific and technological infrastructure—EAST auxiliary heating system project. He also hosted the national ‘13th five-year plan’ major scientific and technological infrastructure—Integrated Research Facility for Critical Systems of fusion reactor comprehensive research facility for fusion technology (CRAFT). Many important scientific and technological problems have been solved and overcome by Prof. Li and his co-workers, which puts China's plasma physics research and fusion engineering technology at the forefront of global engineering.

Electro-Magnetic and Stress Analysis of a −400 T2/m High-Field Gradient Magnet with a Room-Temperature Bore Size of 200 mm

“…Most importantly, as the center-field strength of the magnet increases, the effect of electromagnetic stress in the magnet windings becomes more severe. Given that these types of gradient magnets typically exhibit a substantial central magnetic field strength and a high magnetic field gradient, the operation of the magnets can result in the generation of significant electromagnetic stress in the superconducting coils and supporting structures [16].…”

Preface: mechanical perturbations induced quench: a challenge of superconductor mechanics

“…In this issue, it is a great honor to interview Prof. Jian-gang Li, an academician of the Chinese Academy of Engineering. Prof. Li emphasized that, during the development of fusion energy–oriented high-field superconducting magnets [ 5 ], the influence of mechanics on superconductivity is the fundamental issue and difficulty.…”