| 摘要 |
A method for setting the equivalent fissile coefficient used to determine Pu enrichment degrees corresponding to Pu isotopic compositions to be applied in the production of MOX fuel assemblies, is provided with: a step in which a plurality of Pu isotopic compositions which cover a range of applicable Pu isotopic compositions, and which are greater than the total equivalent fissile coefficient are selected; a step in which the enrichment degree distribution of each of the selected Pu isotopic compositions, said enrichment degree distribution at which arbitrary properties become equivalent to a reference design, is determined for each MOX fuel rod; and a step in which the MOX-fuel-rod average Pu enrichment degree (&egr;) based on the enrichment degree distribution and data based on the weight percentage, in Uranium or Pu, of each isotope in each Pu isotopic composition are used to calculate a formula in which the method of least squares is applied to the equivalent fissile method, and the equivalent fissile coefficient is obtained. As a result, a method for designing and producing MOX fuel assemblies with greater efficiency can be provided with which the equivalent fissile coefficient can be set more accurately than previously possible. |
