Quench experiments on sub-size HTS Cable-In-Conduit Conductors for fusion applications: Data analysis and model validation

The recent experimental campaign, carried out in the upgraded SULTAN facility and supported by EUROfusion, investigated quench propagation in high field, sub-size HTS Cable-In-Conduit Conductors. The available experimental data consist of voltage, jacket and helium temperatures measured along the length of the conductors. In this work, the analysis of experimental data is carried out, focusing on the normal zone propagation velocity and the hotspot temperature reached during the quench. The validation of one-dimensional (1D) thermal-hydraulic and electric numerical models implemented in the H4C code is presented, showing very good agreement between experimental and computed results, both in terms of global and local quantities. The validated tool is then used to assess the impact on the hotspot measured in SULTAN and that reached in a uniform magnetic field configuration, showing that SULTAN measurements provide conservative assessments. The tool is then used to simulate a quench in a real-case scenario, i.e., the EU DEMO Central Solenoid operation, showing that a conventional quench detection strategy based on voltage measurements should suffice, leading to hotspot temperature around 250 K.