Computational Fluid Dynamics Modeling Approach to Evaluate Vsc–17 Dry Storage Cask Thermal Designs

A numerical simulation of flow and heat transfer in a ventilated concrete dry storage cask system–17 (VSC–17) is performed and results compared with experimental data to assess the validity of the computational approach. The measurements of steady state temperature distributions on the cask surface, concrete surface, air flow channels, and fuel canister guide are available. Numerical simulations were carried out for normal operating conditions, where both the inlet and outlet vents are open, and for off-normal condition when normal air circulation is interrupted because of blocked vents. Results include the flow and temperature pattern in the ventilated storage system. Computed results were compared with experimental data for axial temperature distribution along the fuel assembly and radial temperature distribution along the storage assembly system. The effect of the turbulence model on temperature distribution pattern was also studied. For all the simulated cases, the computed results showed a trend similar to the experimental observation but did not model exactly. Computed peak cladding temperature in all the simulation cases was slightly higher than the experimental data. Heat transfer results showed some variation due to difference in backfill gas. A study of different k-ε and k-ω turbulence models showed very little effect on temperature distribution.