Thermo-hydraulic analysis of cooldown for ITER toroidal field coils from 80 K to 6 K

ITER is the next-step large-scale experiment for magnetically confined fusion. Thermo-hydraulic analysis of the cool-down from 80 K to 6 K for TF coils has been carried out recently. This TF coils cool-down stage should be analyzed by considering the influence of the cryoplants. To carry out the simulation, a time-dependent thermo-hydraulic simulation cool-down from 80 K to 6 K stage has been performed by using FORTRAN code. The code for analyzing coils is based on a 1D helium flow and 3D solid heat conduction model. The cool-down model for the thermal and gas dynamic process of the equipments in cryoplants is also developed, which will be described in detail in this report. The simulation results for cool-down of TF coils to 6 K are also discussed, which indicate that cool-down from 80 K to 6 K stage can be completed in 10 days.