Positive reactivity effect in hollow critical assemblies with moderated neutrons

Autor:	V. F. Kolesov, L. F. Gudarenko, T. G. Ivchenko, G. G. Farafontov, V. G. Kudel'kin, S. V. Mzhachikh, R. Ya. Gatilova, G. G. Ivanova, V. Kh. Khoruzhii
Rok vydání:	2000
Předmět:	inorganic chemicals Fission technology industry and agriculture Neutron poison chemistry.chemical_element Nuclear reactor Enriched uranium Molecular physics law.invention Nuclear physics Nuclear Energy and Engineering chemistry Nuclear reactor core law Uranium-235 Neutron Boron
Zdroj:	Atomic Energy. 88:337-344
ISSN:	1573-8205 1063-4258
Popis:	Computational results obtained using the neutron-gas-dynamic codes for fission bursts in supercritical hollow assemblies of fissioning substances with a moderated neutron spectrum, specifically, in assemblies containing a neutron absorber, with a core consisting of a mixture of uranium, enriched to 90% with235U, and polyethylene are presented. Sharp manifestations of positive reactivity in the assemblies and a difference of the effect from that in fast systems are found. It is shown that in assemblies with moderated neutrons, as compared with fast systems, 1) the scale of the increase in the energy release in a burst is substantially reduced by inserting boron into the cavity; 2) in many cases the effect has the classical form with real growth of keff and λ in time; 3) the effect is essentially independent of the properties of the moderator in the cavity; and 4) the effect is less dangerous with respect to nuclear safety. 2 figures, 3 tables, 12 references.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::5bb76981776710859c3894ddf6e008e8 https://doi.org/10.1007/bf02680526 Zobrazit plný text záznamu Full text from SpringerLink