A method to evaluate the maximum allowable temperature of spent fuel in dry storage during a postulated accident

A method is developed to evaluate the maximum allowable temperature and dry storage time of spent fuel under postulated increasing temperature accident conditions, based on creep strain predicted by an empirical creep equation and the creep strain criterion. The creep equation uses the actual stress as the applied stress due to changes in internal rod pressure, fuel rod shape, and volume ratio of free to pellet fuel. It is shown that his method is more realistic and practical than one based on the life fraction rule and the creep rupture criterion. A sensitivity study of the method indicates that the maximum allowable temperature depends on the temperature increase rate, but not the initial normal storage temperature; the allowable storage time, however, depends on both