COMPUTER-IMPLEMENTED METHOD FOR SETTING EQUIVALENT FISSILE COEFFICIENT

摘要

In a method for setting equivalent fissile coefficients used in determining a Pu enrichment corresponding to a Pu isotopic composition to be applied in targeting an MOX fuel assembly as a manufacture object, the method comprises the steps of: selecting multiple Pu isotopic compositions that cover a range of the Pu isotopic compositions to be applied thereto up to a number larger than the total number of the equivalent fissile coefficients; determining an enrichment distribution of each MOX fuel rod that becomes equivalent in arbitrary characteristic to the base design for each of the selected Pu isotopic compositions; and obtaining the equivalent fissile coefficients by calculating an equation obtained by applying a least squares method to an equivalent fissile method using an average Pu enrichment µ of the MOX fuel rods based on the enrichment distribution and data based on a weight ratio that each isotope occupies in uranium or Pu in each Pu isotopic composition; therefore, it is possible to provide a method capable for setting equivalent fissile coefficients for more efficient design and manufacture of the MOX fuel assembly with a higher accuracy than before.