REACTOR CORE NUCLEAR INSTRUMENTATION RESPONSE CALCULATION METHOD

PROBLEM TO BE SOLVED: To improve the accuracy of calculating adjacent node output by using γ-ray response and to improve the accuracy of evaluation of in-reactor output distribution by a three-dimension BWR simulator. SOLUTION: Output from inside a nuclear reactor core equipped with numerous fuel assemblies and control rods is measured with an in-reactor nuclear instrumentation assembly and the measured output is used in the calculation for monitoring output distribution and controlling the reactor core. A detector for measuring heat generation due to γ-ray flux or γ-ray is included by the in-reactor nuclear instrumentation assembly and output of the fuel assembly and response relation of the detector are calculated by the γ-ray transport calculation. In addition to contribution of γ-ray from fuel rods structuring the fuel assembly, a capture reaction of a nuclear instrumentation structure material structuring the in-reactor nuclear instrumentation assembly and γ-ray generated by an inelastic scattered reaction are acquired as calculation elements. COPYRIGHT: (C)2003,JPO