CFD Simulation of Rod Bundles

Abstract

Atomic Energy of Canada (AECL) has initiated a program to develop Computational Fluid Dynamicscapability (CFD) to simulate single-phase and two-phase flow conditions in rod bundles. This paper presents a comparative analysis of turbulence models available in commercial CFD programs for their use in nuclear thermalhydraulic applications. The objective was accomplished using ANSYS FLUENT 6.3.26 for two geometries: a 5×5 bundle with split-type spacers and a 28-element bundle with appendages. Apart from the analysis of the two- and seven-equation models, superior predictive capabilities of the DES (Detached Eddy Simulation) and LES (Large Eddy Simulations) approaches were demonstrated for the 28-element uncrept CANDU fuel channel with appendages.