EXPERIMENTAL-CALCULATION METHOD TO DETERMINE LIFE TIME OF PROMPT NEUTRONS IN ASSEMBLIES FOR VERIFICATION OF NEUTRON-PHYSICAL CALCULATIONS

Authors & Affiliations

Adarchenko V.A., Andreev S.A., Besov S.S., Ershova L.S., Lukin A.V., Sokolov Yu.A., Khmelnitsky D.V.
Russian Federal Nuclear Center – Zababakhin All-Russia Research Institute of Technical Physics, Snezhinsk, Russia

Adarchenko V.A. – Senior Researcher, Cand. Sci. (Phys.-Math.), Russian Federal Nuclear Center – Zababakhin All-Russia Research Institute of Technical Physics.
Andreev S.A. – Head of Department, Cand. Sci. (Phys.-Math.), Russian Federal Nuclear Center – Zababakhin All-Russia Research Institute of Technical Physics.
Besov S.S. – Engineer-researcher, Russian Federal Nuclear Center – Zababakhin All-Russia Research Institute of Technical Physics.
Ershova L.S. – Researcher, Russian Federal Nuclear Center – Zababakhin All-Russia Research Institute of Technical Physics.
Lukin A.V. – Chief Researcher, Dr. Sci. (Phys.-Math.), Professor, Russian Federal Nuclear Center – Zababakhin All-Russia Research Institute of Technical Physics.
Sokolov Yu.A. – Leading Researcher, Cand. Sci. (Phys.-Math.), Russian Federal Nuclear Center – Zababakhin All-Russia Research Institute of Technical Physics.
Khmelnitsky D.V. – Deputy Head of the Department - Head of the Theoretical Laboratory, Cand. Sci. (Phys.-Math.), associate professor, Russian Federal Nuclear Center – Zababakhin All-Russia Research Institute of Technical Physics. Contacts: post box 245, 13, Vasilyev st., Snezhinsk, Chelyabinsk region, Russia, 456770. Tel.: +7(351)465-11-32; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..

Abstract

The work presents experimental-calculation method to determine mean life time of prompt neutrons in assemblies that are investigated on a test-bed for critical assemblies FKBN-2. Besides determination of critical state of assembly on delayed neutrons, it was proposed to calculate the value ∂α/∂H from experimental dependence of asymptotical constant of drop from a gap between upper and lower parts of the system α(H). The value ∂α/∂H characterizes transient processes in subcritical assembly on prompt neutrons and determines mean life time of prompt neutrons up to coefficient ∂K_ef/∂H. The latter value determines mean time of prompt neutron life in the system and along with the results of critical experiments, it can be used for verification and refinement of neutron constants.
The work presents the results of experiments performed on FKBN-2 with assemblies out of metallic uranium and plutonium with their various ratios, in which determination was made for critical states and values of ∂α/∂H. Calculation bench-mark models were created for investigated assemblies, and using Monte-Carlo method and according to PRIZMA code, numerical modeling of critical and correlation experiments was made with various libraries of neutron constants.

Keywords
experimental-calculation method, mean life time of prompt neutrons, assembly, transient processes, verification, neutron constants

Article Text (PDF, in Russian)

References

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UDC 621.039.51

Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2018, issue 2, 2:13

BROND-3.1

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2018, Issue 2

EXPERIMENTAL-CALCULATION METHOD TO DETERMINE LIFE TIME OF PROMPT NEUTRONS IN ASSEMBLIES FOR VERIFICATION OF NEUTRON-PHYSICAL CALCULATIONS