No abstract

No abstract

High fidelity modeling and simulation of nuclear reactors with direct whole core transport calculation has become an important state of art for development of reactor computational tools with the rapidly improvement of computing power. In this work, a quasi-2D delayed neutron precursor (DNP) drift model has been implemented in a GPU-based whole core transport code ThorMOC to achieve high fidelity modeling and simulation of liquid-fueled molten salt reactors (MSRs). A rasterized coarse mesh finite difference (RCMFD) method is applied in ThorMOC to improve the convergence rate, and to handle complex MSR models with arbitrary boundaries by combining with long characteristics method. OpenMC is used to generate a multi-group cross section library and to provide reference results for stationary state calculations. The results including eigenvalue and power distributions from ThorMOC agree well with those from OpenMC for stationary state calculations of the Molten Salt Reactor Experiment (MSRE) model. The reactivity loss due to DNP drift is computed and is in a good agreement with the measured value in experiment.

The liquid-fueled molten salt reactor uses liquid fuel, and its dynamic characteristics are different from the traditional solid fuel reactor. Dynamic modeling and simulation play a key role in the design phase of the innovative reactor system. Based on Modelica language, a Modelica model named TMSRLib (Thorium-based Molten Salt Reactor Library) for dynamic modeling and simulation of liquid-fueled molten salt reactor system is developed using Dymola platform. In order to verify the validity of the developed dynamic simulation model library, two system models of the MSRE (molten salt reactor experiment) with core represented by single region and nine regions are built based on the TMSRLib Modelica library, respectively. Then the two system models of the MSRE are validated by using experimental benchmarks of MSRE. The results show that the numerical results are in good agreement with MSRE experimental results, and verifies the applicability and correctness of each component model in TMSRLib.