The study on the main factors affecting the response analysis of nuclear fuel transport cask drop

Abstract

The nuclear fuel transport cask is an important transport equipment in the nuclear power industry. Rational design requires the structure to maintain integrity and tightness after experiencing severe accident conditions such as a 9 m drop. Therefore, the design and analysis are the key links of container forensics. The calculation of drop analysis involves many factors such as nonlinear material constitutive, complex contact, high strain rate, and large deformation which brings great challenges to the reliability of simulation analysis. Summarizing and sorting out the key factors in the design and analysis of transport casks can solve the practical needs of engineering and guide the analysis and calculation of transport cask drop. This study considered the perspectives of impact limiter design, assembly clearance, analysis model, environmental factors, dropping angle, and the calculation and comparison of buffer materials' dispersion. A two-degree-of-freedom vibration system was used to simulate the impact of clearance collision, and a beam model was applied for the investigation of the response of assemblies. The considerations of the analysis model and the impact of the environment on buffer materials were expounded. Finally, the main conclusions are as follows: the dispersion of buffer materials should be considered in the design. The wood with low compressive strength will cause greater compression deformation, and the wood with high compressive strength will cause greater peak acceleration. The frequency, mass, and clearance of the internal components and the container all affect the acceleration response of the internal structure. The acceleration response is sensitive to the angle under the side and end drop conditions.