The two-phase closed tubular cryogenic thermosyphon

The heat transfer characteristics of a two-phase closed tubular cryogenic thermosyphon filled with nitrogen fluid have been investigated. The thermosyphon consists of a 1.1 cm inside diameter, 5 m long copper tube coated with a few layers of the high-vacuum superinsulation and enclosed into a vacuum jacket. A free-boiling liquid nitrogen pool has been used as a cooling machine. The system is compact, free from mechanical vibrations, and can provide thermal stabilization of remotely located devices in the temperature range of 80–120 K with the heat transfer limit up to 100 W.