Presentation Information
[APP2-05]Feasibility Study of a Stationary Magnetic Refrigeration System using Magnetically Coupled Superconducting Coils for Lunar Hydrogen Liquefaction
*Sakutaro Nagaya1, Shinnnosuke Matsunaga1,2, Hiroto Nanba1, Jun Shimada3, Haruumi Yamamoto2, Kyohei Natsume2, Kouji Kamiya2 (1. National Institute of Technology, Gifu College (Japan), 2. National Institute for Material Science (Japan), 3. Japan Aerospace Exploration Agency (Japan))
Keywords:
Magnetic Refrigeration,Stationary Magnetic Refrigeration
[Purpose]
Future lunar exploration requires in-situ propellant production, including hydrogen liquefaction to 20 K. Conventional cryogenic systems are unsuitable for space due to energy and volume constraints. This study investigates stationary magnetic refrigeration as a compact and efficient alternative, eliminating mechanical actuators.
[Method]
A magnetic refrigeration system using magnetically coupled superconducting coils was designed. The operating sequence consists of three phases: energizing the inner coil for heat rejection, shifting the field outward by demagnetizing the inner coil while energizing the outer coil, and applying reverse current to the inner coil for active demagnetization to induce cooling. Numerical simulations were performed with Femtet, based on the specifications of the experimental apparatus under development.
[Results]
The simulations showed that the central magnetic field generated by the inner coil alone was almost completely cancelled when reverse excitation of the inner coil was combined with excitation of the outer coil. This confirms the effectiveness of reverse excitation for field cancellation in the stationary configuration.
[Consideration]
The results suggest that stationary systems can achieve magnetic field variation without moving parts, providing structural simplification and compactness compared with actuator-driven designs. This makes the approach promising for space environments where mass and volume are constrained.
[Conclusion]
The study demonstrates through simulation that reverse excitation can effectively cancel residual fields, indicating the feasibility of the proposed excitation–demagnetization cycle. Experimental validation with fabricated superconducting coils is currently in progress, and the results will be reported at the presentation.
Future lunar exploration requires in-situ propellant production, including hydrogen liquefaction to 20 K. Conventional cryogenic systems are unsuitable for space due to energy and volume constraints. This study investigates stationary magnetic refrigeration as a compact and efficient alternative, eliminating mechanical actuators.
[Method]
A magnetic refrigeration system using magnetically coupled superconducting coils was designed. The operating sequence consists of three phases: energizing the inner coil for heat rejection, shifting the field outward by demagnetizing the inner coil while energizing the outer coil, and applying reverse current to the inner coil for active demagnetization to induce cooling. Numerical simulations were performed with Femtet, based on the specifications of the experimental apparatus under development.
[Results]
The simulations showed that the central magnetic field generated by the inner coil alone was almost completely cancelled when reverse excitation of the inner coil was combined with excitation of the outer coil. This confirms the effectiveness of reverse excitation for field cancellation in the stationary configuration.
[Consideration]
The results suggest that stationary systems can achieve magnetic field variation without moving parts, providing structural simplification and compactness compared with actuator-driven designs. This makes the approach promising for space environments where mass and volume are constrained.
[Conclusion]
The study demonstrates through simulation that reverse excitation can effectively cancel residual fields, indicating the feasibility of the proposed excitation–demagnetization cycle. Experimental validation with fabricated superconducting coils is currently in progress, and the results will be reported at the presentation.