Accelerating Nuclear Innovation Through Advanced Modeling and Simulation

Traditionally, the simulation of nuclear energy systems has been based on empirical models, which requires extensive experimental data. Although simulations of this type can run quickly, their use is constrained to the system and conditions for which the experiments were designed.

With advancements in nuclear engineering and associated domain sciences, computer science, high-performance computing hardware, and visualization capabilities, new multiscale/multiphysics modeling and simulation (M&S) tools are enabling scientists to gain insights into physical systems in ways not possible with traditional approaches alone. Because these tools rely more on underlying physics than on empirical models, they are more flexible, can be applicable to a wider range of operating conditions, and require less data, i.e., to validate the accuracy of the simulations, rather than the considerable amounts of data required to generate the empirical models of the traditional approach.

The NE Advanced Modeling and Simulation program has engaged researchers and scientists to develop new tools to analyze and optimize the performance and reliability of existing and advanced nuclear power plants. Prior to 2020, these efforts were conducted under two independent, complementary programs: the Energy Innovation Hub for Modeling and Simulation (Hub) and the Nuclear Energy Advanced Modeling and Simulation (NEAMS) program. As the Hub progressed toward its conclusion in June 2020, NE integrated LWR and non-LWR scope and research into the NEAMS program.

Computational tools developed by NEAMS are allowing researchers to gain insights into current problems and advanced concepts in new ways, and at levels of detail dictated by the governing phenomena, all the way from important changes in the materials of a nuclear fuel pellet to the full-scale operation of a complete nuclear power plant.

Furthermore, if advanced reactors are going to be efficiently deployed, it is critical that advanced M&S play a significant role. In addition to lack of experimental data for advanced reactors, significantly different interdependence of neutronics, fuel response, and thermostructural-fluids phenomena also pose unique multiphysics M&S challenges. Therefore, in absence of extensive experimental data and given physics interdependence, more mechanistic/predictive and multiphysics advanced M&S capabilities are essential for these concepts. Ideally, “advanced” M&S should also be “flexible” M&S, where a similar set of tools can be used for initial "low res" scoping/reactor design, and then the same framework applied to optimization using "high res"/mechanistic advanced M&S – and integrated within innovative experimental testing program.

The NEAMS program is committed to working with NRC and vendors to assist the accelerated deployment of advanced LWR technology and non-LWR reactors.