抄録
A concentric-tube two-phase thermosyphon to use sodium as a refrigerant for heat transportation use of the small nuclear reactor for Mars is promising. For the design, the inside of the thermosyphon using the low boiling point refrigerant manufactured for the transparent material was observed. Then, even if the heat transport rate was close to the maximum, it turned out that the flow in the adiabatic section of outside of the concentric tube is two-phase flow. Moreover, it checked that about 70% of performance of the calculated value of ideal conditions was realizable by measuring maximum heat transport rate and comparing with the model calculated value.
