Operation Margin of the ITER Central Solenoid During the Plasma Scenario

For the large-scale fusion magnets of the International Thermonuclear Experimental Reactor (ITER) tokamak, wound with cable-in-conduit conductors, the application of sophisticated numerical models able to analyse the thermal–hydraulic behaviour during plasma scenarios is of paramount importance to guarantee an adequate stability margin during operating conditions. The SuperMagnet code has been developed by CryoSoft with the intent to simultaneously simulate the electrical, thermal and hydraulic phenomena occurring during the operation of superconducting coils. In this work, the SuperMagnet code is applied to analyse the thermal–hydraulic behaviour of the central solenoid of the ITER tokamak under the plasma scenario. The central solenoid (CS) is composed of six modules for a total amount of 240 pancakes. The software is able to tackle the complex structure of the CS and its cryogenic closed loop. In the present work, the circulation pump operation and the heat transfer to the helium bath are investigated. The results presented here show the temperature evolution of the magnet and of the supercritical helium during the plasma scenario, which allows the determination of the operation margin of the CS.