The Use of Supercritical Helium to Cool AHF Lens Magnets

It was envisioned that the superconducting lens magnets for the Advanced Hydrotest Facility (AHF), which was under study at Los Alamos National Laboratory, would be cooled with pool-boiling helium. However, a supercritical-cooling approach would relieve space and other constraints in critical areas, in addition to eliminating potential vapor-trapping in the magnets with the associated heat-transfer degradation. Also, a quench in a string of magnets cooled with supercritical (SC) helium may be easier to handle than for the pool-boiling case. This paper examines various approaches to a supercritical-helium cooled lens system for AHF and compares them to the pool-boiling approach