Assessment of the Accuracy of Computer Simulations for Accident Conditions for Transport Licensing Applications for Spent Nuclear Fuel

The regulations set forth to define the accident conditions for transport of spent nuclear fuel require the 30 foot drop of the transport cask onto a massive unyielding surface. Over the past 15 years, a series of scale model drop tests have been performed which were used to validate the methodology employed to design the components, which limit the deceleration of the cask and its contents (impact limiters). With the availability of improved analytical tools and hardware, the analyses of the impact limiters have become sophisticated, thus requiring improved material characterization. In earlier efforts, the analysis of the impact limiters focused on the predictions of the rigid body motion of the cask. Recent applications have sought to not only characterize the rigid body motion of the cask body, but also the local dynamic response of the cask body. The effort to improve the analytical prediction and the material data has resulted in defining an acceptable methodology to perform the analyses of the accident conditions. This paper reviews the improvements in these areas as well as the improved analysis predictions.