Physics-based multiscale coupling for full core nuclear reactor simulation

TLDR

Numerical simulation of nuclear reactors is key to improving efficiency, safety, and reliability of existing and future designs, historically achieved by linking multiple codes each simulating a subset of multiphysics phenomena. The MOOSE framework enables a new approach where multiple domain‑specific applications built on the same software are efficiently linked via flexible coupling, allowing simultaneous data exchanges on high‑performance parallel hardware. Benchmarks on the KAIST‑3A core and a simplified Westinghouse AP‑1000 show the framework can tackle coupled, multiscale reactor phenomena such as CRUD‑induced power shift and fuel shuffle.

Abstract

Numerical simulation of nuclear reactors is a key technology in the quest for improvements in efficiency, safety, and reliability of both existing and future reactor designs. Historically, simulation of an entire reactor was accomplished by linking together multiple existing codes that each simulated a subset of the relevant multiphysics phenomena. Recent advances in the MOOSE (Multiphysics Object Oriented Simulation Environment) framework have enabled a new approach: multiple domain-specific applications, all built on the same software framework, are efficiently linked to create a cohesive application. This is accomplished with a flexible coupling capability that allows for a variety of different data exchanges to occur simultaneously on high performance parallel computational hardware. Examples based on the KAIST-3A benchmark core, as well as a simplified Westinghouse AP-1000 configuration, demonstrate the power of this new framework for tackling—in a coupled, multiscale manner—crucial reactor phenomena such as CRUD-induced power shift and fuel shuffle.