Authors & Affiliations
A.I. Leypunsky Institute for Physics and Power Engineering, Obninsk, Russia
Gonchar N.I. – Senior Researcher, A.I. Leypunsky Institute for Physics and Power Engineering. Contacts: 1, sq. Bondarenko, Obninsk, Kaluga reg., Russia, 249033. Tel.: +7(484) 399-42-59, e-mail:
An ingress of natural uranium and thorium impurity in clad steel and heavy liquid metal coolant in gaseous fission products activity in cover gas and in delayed neutrons concentration in coolant estimated. The estimation made as an example calculation for reactor with fast neutron spectrum cooled by lead-bismuth eutectic. Cladding failure detection produce by measuring of gaseous fission product activity in cover gas and delayed neutrons abundance in coolant. With the leak tightness of all cladding kept intact the ingress of fission product included the delayed neutron mother nuclide into coolant is due to: process contamination of a cladding surface with fuel composition in the course of fuel element fabrication and natural uranium and thorium impurity in clad steel, fuel assembly cans and heavy liquid metal coolant itself. A fission product activity produced by that ingress in the primary circuit media is starting point to record a fuel element seal failure. Delayed neutron concentration in coolant produced by that ingress is the lower bound of significant clad failure that can be record.
cladding failure detection, heavy liquid metal coolant, natural uranium and thorium impurity, gaseous fission product, delayed neutrons
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