Performance of Two-phase Closed Loop Thermosyphon in Cooling Down of Compact Superconducting Magnet

An experiment to investigate the two-phase closed loop thermosyphon (TPCLT) to cooling the compact superconducting magnet has been performed. This study is motivated mainly by our development of cryogenic cooling for a superconducting cyclotron magnet system. In the two-phase closed loop thermosyphon system, the cooling of the cold mass (27 kg copper block) from room temperature to 4 K is achieved in three stages by refilling subsequently the loop with Nitrogen (80 K), Neon (30 K) and Helium (4 K) based on the different boiling point of each of the gases. The cooldown process and efficiency were analyzed and compared with directly conductor cooling method. The results show that the TPCLT cooling method can reduce the liquid helium and shorten the cooling time, so it has a potential to achieve lower energy consumption and higher efficiency for cooling compact a superconducting magnet (the weight large than 100 kg) in practical applications.