Advanced Analysis of Nuclear Waste Storage Cask Health

At the present, the United States does not have a designated disposal site for used nuclear fuel — the nation therefore faces the prospect of extended long‐term storage (i.e., >60 years) and deferred transportation of used fuel at operating and decommissioned nuclear power plant sites. We need to augment nuclear waste canister Ageing Management programs with Modeling capability that is comprehensive, physics based and can be tailored to different OEM Geometries, Material Properties, use existing data and accommodate data gaps, incorporate incoming inspection data, account for location based environmental conditions, and variability. The site and canister specific results can be derived from the virtual twin simulation model. In Phase I, we established feasibility of the above concept. In Phase II, we developed a Virtual Twin for spent nuclear fuel storage systems. The main elements of the model are as follows: Environmental (atmospheric site conditions), OEM supplied canister design information, Failure Modes, Data-Driven Corrosion Modeling, Synthetic Data Generation (using a high-fidelity multi-physics simulation), Probabilistic Inference, Probabilistic Uncertainty Management, Multi-Model Data Fusion (for integration of Digital Twin and NDE datasets as well as Inspection reports). We focused our efforts into modeling CISCC and welding failure modes that are predominant in this canister. The Virtual Twin model can use a variety of (conflicting, misaligned) simulation models. The majority of these capabilities are enabled by using advance probabilistic models. Having such a tool provides utilities/operators/OEMs and regulators reassurance throughout different stages of development. Also, variety of inspection data can be evaluated via the same Virtual Twin model. Most importantly results of various field data or simulation data can be integrated to provide a comprehensive database. We Are Proposing to Extend and Mature Previous Phase II Work to Include the Following Innovative Features and Improvements:Include Other Manufacturers; Improving Simulation’s Accuracy and Reliability; Consider Effects of Seismic Loads; Consider Transportations Loads; Dual Purpose Canisters (DPC); Expanded GUI; Risk Ranking Analysis; Variability; Include Other external factors. The resulting technology from this effort can be applied initially to assess state of health of canisters used to store nuclear waste. It can also be used for helping utilities with relicensing applications for extending canister useful life. It can be used for a wide range of applications engaged for monitoring of machinery and structural components. The commercial intent is to produce a beta-tested software tool for commercial markets. Potential commercial applications include diagnostics/prognostics of machinery and structural health monitoring.