NEW MODEL INITIAL CORE FUEL ASSEMBLY CONFIGURATION, AND CONFIGURATION METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a new model initial core fuel assembly configuration, and a configuration method therefor.SOLUTION: A new model initial core fuel assembly configuration improves fuel control efficiency in a nuclear reactor, thereby, improves economic efficiency. A configuration method for an initial core comprises the steps of: preparing a plurality of fuel assemblies different in average enrichments of uranium 235; and arranging the plurality of fuel assemblies so as to become an initial core configuration of a configuration for emulating a known equilibrium reload cycle core at least in terms of a spatial reactivity distribution. The resulting average enrichment in the initial core is within a range from below about 1.0 wt.% of the uranium 235 to about 5.0 wt.% of the uranium 235. Design for a new lattice is also disclosed.