Exploring diversion-pathway analysis of a generic molten-salt fast reactor using multiphysics informed signatures
Molten salt reactors are being explored by multiple commercial ventures due to their inherent safety features, flexibility in fuel sources, and high fuel utilization and thermal efficiency. The continual flow of fuel salt, large fissile quantities present, and ability to add or divert material due to the liquid nature introduces new challenges for international safeguards. […]
High-Temperature Gas-Cooled Pebble-Bed Reactors Running In And Transient Modeling Capabilities Demonstration
This study presents a comprehensive benchmarking and verification effort of several thermal-hydraulic and multiphysics capabilities for high-temperature gas-cooled reactor (HTGR) applications. The first part of this effort focuses on the running-in verification of Griffin’s multiphysics capabilities, specifically for simulating the evolution of Pebble Bed reactor cores from startup to equilibrium. In the absence of validation […]
Selection of Sampling and Surrogate Modeling Methods for State-Point Evaluations of an AGN-201M Reactor
Nuclear reactor digital twins have been proposed for use as a safeguards technology to efficiently monitor new and novel reactors as they come online. A safeguards digital twin needs to be capable of detecting misuse and diversion as it occurs, requiring physics models to be accurate and efficient. Mathematical surrogate models are capable of achieving […]
Capturing the Run-In of a Pebble-Bed Reactor Using Thermal Feedback and High-Fidelity Neutronics Simulations
Modeling the run-in of a pebble-bed reactor (PBR) can be challenging as a result of changes in the power, fuel type, and temperatures that occur throughout the run-in period. Previous work utilized high-fidelity neutronics simulations or lower-fidelity coupled neutronics/thermal-hydraulics models to capture the general characteristics of the run-in process. The present work employs high-fidelity neutronics […]
Preliminary Analysis of a Nuclear Grade Sandwich Composite for Transportable Micro-Reactor Shielding
Transportable microreactors pose a unique shielding challenge compared with conventional reactors. Many vendors are seeking to transport a microreactor to a site, operate it for a number of years, and then transport it to a secondary site. This involves ensuring the reactor has sufficient shielding during operations and post-irradiation transportation to ensure the safety of […]
High-fidelity simulations of the run-in process for a pebble-bed reactor
Pebble-bed reactors (PBRs) rely on a continual feed of fuel pebbles being cycled through the core. As a result, they require a “run-in” period in order to reach an equilibrium state. The run-in period for a PBR is a complex, time-dependent problem that requires the injection of new fuel, different types of fuel, and power […]
Multiphysics Pebble-Bed Reactor Control Rod Withdrawal Study
This work studied the responses of both a generic gas- and a fluoride-cooled PBR concept—the gPBR-200 and gFHR, respectively—during reactivity insertion accidents. Both models rely on 2-D axisymmetric simulations to solve the neutron flux distribution, nuclide concentrations, and temperature across the core—in addition to numerous representative pebble and TRISO particle simulations for determining fuel and […]
Establishing a Methodology for Performing a Multiphysics Run-In Analysis of the GPBR200
Slide deck of ART annual meeting
A Multiphysics Model of the Versatile Test Reactor based on the MOOSE Framework
The traditional modeling approach for sodium fast reactor cores relies on separate physics models, where the fuel performance, thermal–hydraulics, and neutronics calculations required to predict the core physics characteristics for nominal conditions are decoupled by relying on user-imposed boundary conditions. This paper aims at evaluating the impact of multiphysics simulations for predicting the core characteristics […]
Demonstrate Capability of NEAMS Tools to Generate Reactor Kinetics Parameters for Pebble Bed HTGRs Transient Modeling
The system analysis of anticipated operating occurrences and design basis accident for pebblebed reactor systems requires knowledge of the neutron kinetic parameters. These parameters take into account various types of feedback from the pebble-bed core and are typically integrated into system analysis tools such as the System Analysis Module (SAM) in the Nuclear Energy Advanced […]