Multilayer radiation shielding assessment of the Korean SMART small modular reactor

Small Modular Reactors (SMRs) are recognized as a sustainable and versatile nuclear energy solution due to their enhanced safety features, scalability, and adaptability. In this context, this study evaluates the radiation shielding performance and thermodynamic efficiency of the Korean SMART SMR. A multilayer shielding system, comprising SS316L, water, lead, and tungsten, was proposed and assessed using SERPENT, FLUKA, and GEANT4 simulations. Primary neutrons of 6.81 x 1010 (4.5 MeV), 5.90 x 1011 (500 keV), and 2.88 x 1011 (0.025 eV) were effectively attenuated, while secondary gamma-rays and neutrons were reduced to near zero at the outer layers. Energy and exergy efficiencies were 30.41 % and 60 %, respectively, indicating minimal performance compromise due to shielding. These results demonstrate a robust shielding design that ensures safe operation of compact SMRs and supports their deployment in diverse environments, including electricity generation and modular energy systems. The study also highlights the integration of advanced computational tools for comprehensive assessment of SMR performance and radiation safety, providing a foundation for optimizing shielding materials in next-generation nuclear energy applications.