Simulation of Quench Tests of the Central Solenoid Insert Coil in the ITER Central Solenoid Model Coil.

To investigate the conductor behavior during a quench, quench tests of the Central Solenoid Insert Coil (CSIC) in both DC and pulse modes were carried out with various initial conditions in the Central Solenoid Model Coil Facility. The Nb₃Sn cable-in-conduit conductor with a similar design and configuration to the conductor for the ITER Central Solenoid (CS) was used. The inductive heater, attached on the conductor at the center of the length and the highest field region, initiated an artificial quench in the quench tests. A quench has also occurred during the pulse operation with the ramping rates of 0.4–2 T/s, in the ramp rate limitation tests of the CSIC. Simulations of electric, thermal and hydraulic behavior of the conductor during quench tests were carried out by using the ‘Gandalf’ thermohydraulic simulation code. The experimental results were compared with the simulation and good agreement was obtained. The implication for quench detection in ITER is also discussed and it is confirmed that the hot spot temperature of the ITER-CS is lower than the design criteria (<150 K). [ABSTRACT FROM AUTHOR]