Method of operating a reactor

Purpose: In a BWR type reactor, to feed back the result obtained by judging the degree of fuel element failure to the reactor operating method thereby to precisely prevent the failure of fuel. Method: Flow quantities, pressures, temperatures, neutron fluxes and the like of respective parts of the reactor are detected by measuring systems, the power distribution of each fuel rod is calculated, the power hysteresis of each fuel rod is memorized in a memory device, and the power fluctuation quantity is calculated. Information thus obtained as to the failure probability of fuel rods is fed back to the reactor operating method thereby to prevent failure of the fuel rods. (Aizawa, K.)