ESFR-SMART Core Safety Measures and Their Preliminary Assessment

A large 3600 MW-thennal European sodium fast reactor (ESFR) concept has been studied in a European Horizon-2020 project since September 2017, following an earlier European project. In the paper, we describe new ESFR core safety measures focused on prevention and mitigation of severe accidents. In particular, we propose a new core configuration for reducing the sodium void effect, introduce passive shutdown systems, and implement special paths in the core for facilitation of molten fuel discharge in order to avoid recriticalities after a hypothetical severe accident. We describe and assess the control and shutdown system, and consider options for burning minor actinides.