Progress in on-going experimental and computational fluid dynamic investigations within a CANDU fuel channel

The present work investigates the velocity field within a simplified CANDU fuel bundle with Computational Fluid Dynamic (CFD) simulations and Magnetic Resonance Velocimetry (MRV). MRV is a relatively new experimental method that is not prone to many limitations inherent to conventional fluid flow measurement techniques. Initial results of a simplified non-deformed bundle are presented as a proof-of-concept study, while simultaneously introducing the MRV technique to the nuclear thermal–hydraulics community. The CFD predictions are generally in good agreement with experimental results, both of which reveal complex turbulent behaviour, including rotation, swirl and vortex shedding. This work presents progress in a greater effort to understand the fluid behaviour through a deformed fuel bundle in the context of safety.