Thermal Analysis of a 9977 Package During a KAC Fire Accident

Abstract

Abstract The 9977 is a US Department of Energy (DOE) shipping package used to store and transport plutonium bearing materials. The shipping package utilizes a single 6-inch diameter containment vessel with the radioactive material within SAVY-4000 containers, 3013 food-pack containers, or other sealed storage containers separated by spacers. The 6-inch containment vessel is surrounded by load distribution fixtures and a foam insulation overpack to protect against fire and impact events. A storage facility fire, which is longer and hotter than the regulatory transportation fire, is evaluated to ensure radioactive material containment is maintained. A sensitivity analysis of foam insulation reduction is considered with foam eliminated either along the inside wall of the drum body (Inner Foam) or eliminated from the outer walls of the inner chamber where the 6-inch containment vessel is located (Outer Foam). These options were considered to conservatively simulate the potential foam reduction possibilities due to aging during storage. Note that the foam insulation thermal properties were limited to their beginning of life or “as built” property values. A minimum foam thickness needed to maintain containment during the hypothetical facility fire is determined for both the Inner and Outer Foam configurations as well as for both the SAVY-4000 and 3013 food-pack container configurations.