Feasibility of self-stabilized superconducting cables cooled with He II

The fountain effect induced by heat dissipation in a superconducting composite sweeps away the warmed He II so that the liquid temperature surrounding the normal spot is maintained such that it never reaches the saturated vapor pressure or the λ-line. To study the feasibility of a self-stabilized superconducting cable based on this principle, the authors have investigated how the superflow raises the critical heat flux Q_c (of superfluidity) by means of a flexible superleak filter. It is shown that not only Q _c but also the peak heat flux to the film boiling state can be considerably increased by superflow. In the confined space of a cooling channel, the superflow is expected to dominate the heat transport rather than the Gorter-Mellink conduction known to exist in compact windings in superconducting magnets