This project will develop a series of high-fidelity multiphysics calculations of fast spectrum nuclear reactor configurations. These calculations are needed to eliminate modeling uncertainties in the calculation of important safety parameters, specifically “hot channel factors”. The use of high fidelity multiphysics methods can reduce or eliminate modeling uncertainties due to more accurate geometry and physics representations of the system. Consequently, such simulations could dramatically improve reactor economics by allowing the reactor to operate at higher power while still maintaining safety margins from the design limit.

In order to reduce the significant computational cost of using high-fidelity tools on explicitly modeled full-core reactor geometries, the project will also explore the use of high fidelity tools as a “zooming” tool. In the “zooming” concept, local regions of interest are represented with full fidelity and other regions are represented with much coarser geometry representation. This approach can reduce the overall calculation cost and make high fidelity tools much more computationally feasible for a larger array of problems.

All calculations will be performed with the DOE NEAMS-developed SHARP Toolkit, which includes the PROTEUS neutronics code and the Nek5000 thermal hydraulics/computational fluid dynamics code. This project has high relevance to DOE mission because it enables fast reactor designs that benefit the nuclear fuel cycle. The science goals of this project are directly requested by the DOE NEAMS program under the “SFR Grand Challenge Problem Workpackage.”