Critical safety design method for spent fuel transportation and storage equipment

摘要

PPROBLEM TO BE SOLVED: To provide critical safety design program for a transportation cask for spent fuel and a storage rack for the spent fuel adopting a rational burn-up credit. PSOLUTION: A burn-up of a fuel assembly calculated by a fuel design code based on a collision probability method and a void rate dependent nuclear constant are converted into a transportation cross-section, a portion corresponding to the burn-up of the fuel assembly obtained from a reactor core process computer and an average void rate provided by averaging the void rates in the whole combustion period is extracted out of the transportation cross-section to prepare a transportation cross-section of a spent fuel assembly, and noncritical degrees of the equipments for transporting and storing the spent fuel assembly are calculated by an energy multigroup Monte Carlo method, using arrangement when the transporting and storing the spent fuel assembly, and the transportation cross-section of the spent fuel assembly. PCOPYRIGHT: (C)2006,JPO&NCIPI