SUBCRITICALITY MEASUREMENT METHOD OF NUCLEAR FUEL

摘要

PROBLEM TO BE SOLVED: To precisely measure and evaluate the subcriticality of a measurement object based on a measured value even when detailed information relating to a state parameter of the measurement object including a nuclear fuel is unknown.SOLUTION: A subcriticality measurement method of a nuclear fuel according to the present invention sets a plurality of simulation calculation systems having a virtual measurement object including the nuclear fuel and a virtual neutron detection unit, and for the plurality of simulation calculation systems, obtains a plurality of simulation values of a neutron effective multiplication factor of the virtual measurement object and a reactor noise method measurement value, respectively. A correlation formula of the reactor noise method measurement value and the neutron effective multiplication factor are calculated from the plurality of simulation value. A measured value of the reactor noise method measurement value measured by the actual neutron detection unit is obtained for a measurement system having an actual measurement object including the nuclear fuel and the actual neutron detection unit, and the neutron effective multiplication factor of the actual measurement object, and consequently, the subcriticality are calculated by assigning the measured value of the reactor noise method measurement value into the correlation formula.SELECTED DRAWING: Figure 1