| 摘要 |
PROBLEM TO BE SOLVED: To provide a service life monitoring method of a control rod, capable of more accurately evaluating a service life of a control rod. SOLUTION: On the basis of inputted neutron detection signals, an output distribution operation part 11 obtains an average output P<SB POS="POST">ave</SB>of a core and a relative segment output P<SB POS="POST">j</SB>of a fuel assembly j adjacent to the control rod in a cell i. A heat output operation part 13 calculates a sum W<SB POS="POST">i</SB>of heat output per two adjacent fuel assemblies to one blade of the control rod by W<SB POS="POST">i</SB>=P<SB POS="POST">ave</SB>×ΣP<SB POS="POST">j</SB>. A conversion coefficient operation part 16 uses the sum W<SB POS="POST">i</SB>of each heat output to obtain a conversion coefficientγto be used when obtaining an entire neutron absorption amount in each blade of the control rod. An entire neutron absorption amount operation part 15 uses the sum W<SB POS="POST">i</SB>of the heat output, the conversion coefficientγand time t to calculate the entire neutral absorption amount in each blade of the control rod by W<SB POS="POST">i</SB>×γ×t=P<SB POS="POST">ave</SB>×Σ(P<SB POS="POST">j</SB>×γ)×t. On the basis of the calculated entire neutron absorption amount, a nuclear service life of the control rod is evaluated. COPYRIGHT: (C)2013,JPO&INPIT |
