A new fast and robust thermo-hydraulic code for ITER superconducting magnet simulation

A new software is being developed for plasma pulse scenario validation of the ITER magnet system behaviour and prediction of the margin to quench in superconductors. The principal idea behind this project has been to develop a software tool for the thermo-hydraulic simulation of superconducting magnets that is able to simulate different operations scenarios for the magnets at least an order of magnitude faster than real time. To achieve this level of performance, a tight coupling between the Cable-In-Conduit-Conductors and the structure of the magnet is performed. All the equations for the flow and heat conduction parts of the global model are put in a single sparse system that is integrated in time. Such tight coupling in combination with implicit time stepping allows much longer time steps whilst keeping high accuracy of the solution. The code named REIMS (Riemann Explicit Implicit Magnet Simulator) is still under development. Both central solenoid (CS) and toroidal field (TF) ITER magnets are available at this stage. The development of the different intermediate steps that led to the current version of the code required verification/validation against exact solutions, experimental data and/or comparisons with existing codes. In the same way, results obtained with REIMS for the simulation of both CS and TF loops after application of a short plasma pulse scenario have been compared to results from existing reference codes, showing a good agreement.