Maslov O. The system of radiation technological control of burnup fuel of light water nuclear power installations

The dissertation is devoted to development of a system of Radiation Technical Control (RTC) for revealing of depressurized hulls of fuel rods and determining the burnup of Nuclear Fuel (NF) via measurements of (-radiation of Fuel Assemblies (FA). The analysis of FA exploitation conditions with large burnup has been carried out. The methods for estimation of Irradiated Nuclear Fuel (INF) burnup have been analyzed and generalized. The simulation of line and apparatus spectra of (-radiation of FA which allows one to describe specific radioactivities of basic fission product (FP) with account of effectiveness of registration and self-absorption depending on the initial enrichment of NF with isotope 235U, burnup, reactor WWER-1000 being in the basic working regime and the time of delay after extracting out of the Reactor Core (RC) has been carried out. The ratio of different isotopes of FP being in INF has been modeled. On the basis of a spectrometer with CdZnTe-semiconductor detector, a prototype of tech nical means for measuring INF, has been created. Measurements for more than 200 FA have been carried out and experimentally determined parameters of the model have been defined. The dependencies for control of fuel burnup and identification of FA with a defect fuel rod have been established.