Title:
NEUTRON MONITORING DEVICE, AND SPENT NUCLEAR FUEL CRITICALITY MANAGEMENT METHOD
Document Type and Number:
Japanese Patent JP2023030895
Kind Code:
A
Abstract:
To provide a neutron monitoring device and the like that can determine without a time delay whether the cause of fluctuation of a neutron counting rate is a fluctuation of the degree of subcriticality, a fluctuation of an isotope composition of plutonium, or a fluctuation of the number of generated neutrons by a disturbing nuclide such as curium and the like.SOLUTION: A neutron monitoring device comprises: neutron counting rate measurement means; means of calculating plutonium concentration from a neutron counting rate, and issuing a warning when the plutonium concentration exceeds a setting value; means of calculating a period from time-series data on the neutron counting rate, and issuing a warning when the period exceeds a setting value; means of calculating a variance-to-mean ratio of data on a plurality of neutron counting rates with respect to a certain measurement time width from the time-series data on the neutron counting rate, and issuing a warning when the variance-to-mean ratio exceeds a setting value; and means of calculating a prompt neutron attenuation constant α on the basis of a reactor noise method, and obtaining the degree of subcriticality by using this α, a delayed neutron ratio β preliminarily obtained by an analysis, and a prompt neutron lifetime L.SELECTED DRAWING: Figure 1
Inventors:
YOSHIOKA KENICHI
SUGITA TSUKASA
ODA TADAYOSHI
ODANAKA SHIGERU
SUGITA TSUKASA
ODA TADAYOSHI
ODANAKA SHIGERU
Application Number:
JP2021136299A
Publication Date:
March 08, 2023
Filing Date:
August 24, 2021
Export Citation:
Assignee:
TOSHIBA CORP
TOSHIBA ENERGY SYSTEM & SOLUTION CORP
TOSHIBA ENERGY SYSTEM & SOLUTION CORP
International Classes:
G21C17/06; G01T3/00; G21C17/12; G21C19/40
Attorney, Agent or Firm:
Patent Attorney Sakura International Patent Office