A transfer cask serves as the container for transporting and handling canisters loaded with spent nuclear fuels from light water reactors. This study focuses on a cylindrical transfer cask, standing at 5,300 mm with an external diameter of 2,170 mm, featuring impact limiters on the top and bottom sides. The base of the cask body has an openable/closable lid for loading canisters with storage modules. The transfer cask houses a canister containing spent nuclear fuels from lightweight reactors, serving as the confinement boundary while the cask itself lacks the confinement structure. The objective of this study was to conduct a structural analysis evaluation of the transfer cask, currently under development in Korea, ensuring its safety. This evaluation encompasses analyses of loads under normal, off-normal, and accident conditions, adhering to NUREG-2215. Structural integrity was assessed by comparing combined results for each load against stress limits. The results confirm that the transfer cask meets stress limits across normal, off-normal, and accident conditions, establishing its structural safety.

This study aims to evaluate the heat transfer characteristics and energy consumption in the wet and dry ondol systems. Conditions of the continued heating mode set the room temperature at 20℃ and hot water supply temperature at 60℃ and 70℃ for 3 days. The scheduled heating mode operates heating at 6～9am (room temperature at 20℃), suspends heating at 9～18pm (leaving mode), and runs heating at 1 8～24am (room temperature at 20℃) and 24～6am (room temperature at 17℃) for 2 days. The results from the continued heating mode in the dry/wet ondol systems confirmed that the dry and wet systems had the same average indoor temperature (18.9℃) and similar energy consumption. In addition, the results from the scheduled heating mode in the dry/wet ondol systems confirmed that the dry ondol system had lower energy consumption than the wet ondol system. Therefore, the scheduled heating mode in the dry ondol system is expected to reduce energy consumption.