Viktoriia Hozhyk

PhD Student
Department of Engineering
University of Cambridge

Contact: vh348@cam.ac.uk

Sponsor: Cambridge Trust and Wolfson College

Fluoride salt-cooled high-temperature reactor design leveraging the advanced gas-cooled reactor technology

Fluoride salt-cooled high-temperature reactors (FHRs) are a novel advanced reactor concept that utilises molten salt as a coolant and is fueled by conventional solid fuel. FHRs offer significant advantages compared to currently operating commercial LWRs, such as high efficiency and the possibility of industrial heat applications.

Acknowledging several shared characteristics with the British advanced gas-cooled reactor (AGR), studies have shown that adopting AGR features into FHR designs has beneficial implications, leading to substantial power uprates and/or wider safety margins.

This project aims to build upon ongoing AGR-FHR efforts and design a feasible molten salt-cooled reactor core resembling AGR geometry while staying within acceptable safety and economic limits. Thus far, AGR-like FHR designs have assumed the presence of graphite in the core as a moderating and structural material.

One of the primary areas of interest is constraining the design space search to nearly or entirely graphite-free cores, as previous studies indicated that these designs have the most favourable neutronic characteristics. Moreover, irradiation-related changes in graphite structure have been identified as key life-limiting issues in the current fleet of AGRs. A feasibility assessment of the neutronics and thermal-hydraulics of such graphite-free systems is planned, followed by appropriate core sizing, reactivity control design, and fuel cycle studies.