NEUTRONICS AND THERMAL-HYDRAULICS OF PRESSURIZED WATER REACTOR WITH THORIUM-BASED FUEL

In the present study, the coupled behavior of thermal-hydraulic processes and solid mechanics phenomena was investigated using the finite element method implemented within the COMSOL Multiphysics environment. Neutronic analyses were performed using the OpenMC code under the steady-state neutron transport approximation. To optimize the core configuration of a thorium-fueled pressurized water reactor (PWR), high-pressure light water was selected as the coolant and moderator. The reactor core was composed of 49 fuel rods containing thorium-based fuel compounds arranged in a regular lattice configuration. Monte Carlo neutron transport simulations conducted with OpenMC enabled the evaluation of the effective neutron multiplication factor (k_eff) and the spatial power distribution within the reactor core. Thermal-hydraulic calculations yielded detailed temperature and coolant velocity distributions, while solid mechanics analyses provided the corresponding spatial distributions of stresses and deformations arising under operational conditions. The obtained results demonstrate the applicability and effectiveness of a coupled multiphysics approach integrating steady-state neutronics with thermal-hydraulic and structural analyses for the assessment and optimization of thorium-fueled pressurized water reactor systems.

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