Ventilation pattern and heat dissipation characteristics of a vertical dry storage cask for spent nuclear fuel: Wind tunnel experiments and CFD simulations

•A vertical dry storage cask for spent nuclear fuel is our target.•Ventilation patterns and heat dissipation were experimentally and numerically investigated.•Parameters include approaching wind angle (θ) and Reynolds number (Re).•Re = 8 × 104 is a critical condition for the channel airflow pattern in θ = 0° cases.•When θ = 45°, different wind velocities result in similar channel airflow patterns. In this study, wind tunnel experiments and computational fluid dynamics (CFD) simulations were conducted to observe the channel airflow patterns and heat dissipation characteristics of dry storage casks for spent nuclear fuel. The parameter ranges were as follows: model scale = 1/10, Grashof number (Gr) = 1.0 × 1011, approaching wind angle (θ) = 0° or 45°, and Reynolds number (Re) = 2.6×104-8.0×105. The results show that a wind velocity = 3 m/s (Re = 8 × 104) is a critical condition for the channel airflow pattern inside the cask for cases in which θ = 0°. When θ = 45°, different wind velocities result in similar channel airflow patterns. As the wind velocity increases, the overall average surface temperature of the canister decreases, and the decrease lessens as the wind velocity increases.