Neutronic evaluation of a thermo-hydraulically optimized 50 MWth molten salt fast reactor
Annals of Nuclear Energy, cilt.238, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 238
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.anucene.2026.112540
- Dergi Adı: Annals of Nuclear Energy
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Compendex, Environment Index, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Anahtar Kelimeler: Core Geometry Optimization, Fuel Burnup, Molten Salt Fast Reactor (MSFR), Neutron Spectrum, Neutronic Analysis
- Gazi Üniversitesi Adresli: Evet
Özet
This study investigates the neutronic performance of a thermally–hydraulically optimized curved-core geometry for a 50 MW molten salt fast reactor (MSFR). Six reactor vessel configurations with different upper and lower reflector wall angles were analyzed to evaluate the influence of geometric modifications on neutron spectrum characteristics, reactor criticality, spatial neutron distributions, fuel burnup, and isotopic evolution. Coupled thermal–hydraulic and neutronic simulations were performed using ANSYS Fluent and the MCNP6.3.1 Monte Carlo code with the ENDF/B-VIII.1 nuclear data library. The LiF–UF4 fuel salt was modeled as a Newtonian fluid, and time-dependent isotopic variations were tracked through the MCNPAS interface code. The results indicate that increasing the reflector wall angle from Model 1 to Model 6 reduces the effective multiplication factor from 1.049 to 1.023 due to increased neutron leakage and absorption in the surrounding B4C shielding. Accordingly, the critical operating period decreases from 1755 days to 864 days, leading to a reduction in the achievable fuel burnup from approximately 90,000 to 50,000 MWd/t. Burnup analysis shows depletion of 235U and the conversion of 238U into transuranic isotopes, primarily 239Pu with smaller amounts of 238Pu, 240Pu, 241Pu, and 237Np. The findings highlight the importance of integrated neutronic and thermal–hydraulic optimization in the design of advanced small modular molten salt reactor systems.