Investigation of Experimental Dispersion Fuel Elements with an Aluminum-Based Matrix for High-Flux Research Reactors

Abstract

A variant of experimental dispersion fuel elements with fuel based on uranium dioxide as fi ssile material in a silumin matrix, which have been proposed for modernizing the core of the SM reactor and are irradiated in a wide spectrum of neutron-physical and thermophysical parameters in the refl ector channel of the reactor, is investigated. A nonuniformity with fuel density two times higher than the average over a fuel element, viz., a cluster of uranium dioxide particles in the central zone of the kernel, has been found in the distribution of the fuel phase in the fuel elements. The thermophysical calculations show that for such a distribution of fuel particles the temperature of the fuel composition with heat fl ux density from the fuel-element surface >6 MW/m 2 can reach the melting temperature of the matrix. This is confi rmed by investigations of fuel elements with appreciably larger volume and shape change. To increase the serviceability of the fuel elements, ways of improving their design and the material composition of the fuel mix are proposed.