Scaling method for storage vaults based on thermal-hydraulic characteristics

In this study, natural convection cooling phenomena in storage vaults for spent nuclear fuel were examined. The results revealed a relationship between the geometric length and heat flux of spent fuel cylinders. Such a correlation would be useful in dimensionally scaled storage vaults for experimental investigations of thermal and fluid flow properties. The relationship was applied to five scaled storage vaults, and the resulting thermal and fluid flow characteristics were investigated and compared with those of a full-scale storage vault. The thermal characteristics of the original and scaled storage vaults were in good agreement. The dimensionless temperature, dimensionless resident time, Euler number, and Richardson number were used to compare the behavior of structures with different dimensions, and the obtained data were in agreement within 5.1%. A 1/4-scale storage vault was constructed using the scaling methodology, and the temperature distribution was experimentally measured. The temperature distributions of the measured and simulated structures were found to be in good agreement, demonstrating that the proposed approach is effective for designing scaled-down storage vaults for experimental analyses.