Application of Helium-Based oscillating heat pipes in cryogenic superconducting system

Copper is the cooling transfer material used in cryogenic superconducting systems. Its effective thermal conductivity (ETC) in the 4 K region is only 400 W & sdot;m- 1 & sdot;K- 1, which leads to disadvantages such as large temperature differences and delayed temperature fluctuation. These restrict the improvement of the cooling performance of superconducting magnets. Oscillating heat pipe (OHP) has an ETC of two orders higher than copper, but it is unknown whether the heat generated by superconducting magnets excites OHP to produce oscillatory behavior. It limited its application in superconducting systems. In this study, the structure of helium-based OHP is designed, the heat transfer performance test rig in the 4 K region is constructed, and the numerical simulation method of the gas-liquid two-phase flow and heat transfer process of OHP is built. The oscillating power interval including the trigger power, the dryout power, the width of the power interval, and the optimal heating power is obtained with the heating power is 0.05 W - 1 W, the liquid filling ratio is 10 %-90 % and the turns is 1-6. And the change rule of oscillating power interval is revealed. The research results provide reliable data for the application of helium-based OHP in cryogenic superconducting systems.