AbstractThe present work discussed the risks and consequences of multiple failure sequences for the Safety and Environmental Assessment of Fusion Power (SEAFP) tokamak concept. We analysed a double LOCA scenario within the divertor cooling loop; it starts with an ex-vessel LOCA, inducing an in-vessel LOCA. The induced in-vessel LOCA is due to a thermal crisis occuring in the plasma facing divertor structures, leading to suddenly enhanced thermo-mechanical stresses likely to cause a rupture. We wanted to calculate, as accurately as possible, the overpressure within the different compartments that are involved in the scenario, in order to verify that the design limits of these compartments are not exceeded. We calculated the transients with the help of the CATHARE code for the coolant loop analysis and the CONTAIN code for the containment analysis. A coupling was made, using the Parallel Virtual Machine (PVM) Sofware system on a Unix computers network; the results are compared to those of a manual coupling.
Thermohydraulic responses of a water-cooled tokamak fusion DEMO to loss-of-coolant accidents