Development of a partitioned coupling method based on multi-scale data exchanges between porous and CFD solvers for a nuclear core

Abstract

The objective is to perform multi-scale simulations of flows across a fuel rod bundle with coupling methods between a sub-channel code that takes advantage of the very general features and a CFD code representing the realistic three-dimensional features. Then, a supervisor code ICoCo is used to perform the coupling work based on a partitioned implicit domain decomposition technique. Two domains exchange thermal–hydraulics variables at the coupling interface with specific treatments (prolongation and restriction). When the flow is perpendicular to the coupling interface, non-intersecting domain decomposition approach is applied; otherwise, local domains should be partially overlapping. A verification procedure with increasing complexity is described, and related results employed CFD resolved simulations as references. The MANIVEL benchmark experiment has been chosen as the demonstrative case to validate developed methods by comparing velocity distributions and pressure variations.