Thermal behavior of liquid nitrogen heat pipe to wide range of heat loads

WANISON Ramnarong （総研大）； KIMURA Nobuhiro （KEK）； MURAKAMI Masahide （筑波大）

Abstract:A study of cryogenic heat pipe is ongoing as a fundamental research in cryogenic engineering. It is the primary research purpose to survey the thermal behavior of heat pipes to a wide range of heat load; from the normal heat pipe to the local dry-out states. The heat pipes tested are commercially available ones but working fluid was replaced by liquid nitrogen. The shape of the tubular copper heat pipes is; 6 mm in the outer diameter and 200 mm long, with axial grooves and sintered metal wick. The performance of heat pipes with different liquid filling ratios was tested. The effective thermal conductivity and the axial temperature distribution were measured for a wide range of heat load. The thermal behavior in the local dry-out state for large heat input was also examined for the potential applications to a heat pipe heat switch. The possibility of commercially available heat pipe as a cryogenic heat pipe will be presented and discussed in this conference.