Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Multilayer Neutron Reflectors

12/20/2024 2024 - #04 Physics and technology of nuclear reactors

Shmelev A.N. Apse V.A. Kulikov G.G. Kulikov E.G.

DOI: https://doi.org/10.26583/npe.2024.4.03

UDC: 621.039.5

The paper considers the use of multilayer neutron reflectors to slow down the kinetics of a fast reactor. The reflector is represented in the form of three layers: a transport layer, a moderating layer and a reflecting layer. The first layer should consist of a material with a heavy atomic weight for maintaining a fast spectrum in the core and for deep penetration of neutrons into the reflector. Subsequent layers of the reflector should contain materials with increasingly lighter atomic weights to effectively slow down and reflect neutrons to reduce so the overall reflector thickness. Moreover, all materials should have an extremely low neutron absorption cross-section in order to reduce their inevitable loss in physically thick reflectors.

Taking into account the specified requirements, particular materials (208Pb, 208PbO, 208Pb3O4, 208PbO2, 208Pb(15NO3)2, 208Pb13CO3, 208PbCO3, 13С, 12С, D2O) are proposed for use as the fast reactor neutron reflector to slow down the reactor kinetics and improve nuclear safety.

The studies performed indicate that the development of new fast reactors should advisably include the formation of desired reflector neutron characteristics (both in terms of neutron fraction and delay time, and in terms of energy spectrum) which affect the nature of the evolution of kinetic processes. This situation is radically different from traditional emitter delayed neutrons, which have very limited or no effect.

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fast reactor neutron reflector delayed neutrons 208Pb graphite

Link for citing the article: Shmelev A.N., Apse V.A., Kulikov G.G., Kulikov E.G. Multilayer Neutron Reflectors. Izvestiya vuzov. Yadernaya Energetika. 2024, no. 4, pp. 34-46; DOI: https://doi.org/10.26583/npe.2024.4.03 (in Russian).

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