Forced two-phase helium cooling scheme for the Mu2e transport solenoid

[摘要] The Mu2e Transport Solenoid (TS) is an S-shaped magnet formed by two separate but similar magnets, TS-u and TS-d. Each magnet is quarter-toroid shaped with a centerline radius of approximately 3 m utilizing a helium cooling loop consisting of 25 to 27 horizontal-axis rings connected in series. This cooling loop configuration has been deemed adequate for cooling via forced single phase liquid helium; however it presents major challenges to forced two-phase flow such as "garden hose" pressure drop, concerns of flow separation from tube walls, difficulty of calculation, etc. Even with these disadvantages, forced two-phase flow has certain inherent advantages which make it a more attractive option than forced single phase flow. It is for this reason that the use of forced two-phase flow was studied for the TS magnets. This paper will describe the analysis using helium-specific pressure drop correlations, conservative engineering approach, helium properties calculated and updated at over fifty points, and how the results compared with those in literature. Based on the findings, the use of forced-two phase helium is determined to be feasible for steady-state cooling of the TS solenoids.

[发布机构] Fermi National Accelerator Laboratory, PO Box 500, Batavia; IL; 60510-5011, United States^1

[效力级别] 物理学 [学科分类] 材料科学（综合）

[关键词] Cooling loops;Helium cooling;Horizontal axis;Single-phase flow;Single-phase liquids;Specific pressure;Steady state;Two phase helium