Authors & Affiliations
Lapin A.S., Blandinsky V.Yu., Kolesov V.V., Vnukov R.A., Nevinitsa V.А., Rodionova E.V., Kuzenkova D.S., Fomichenko P.A., Tsybulsky S.V.
National Research Center “Kurchatov Institute”, Moscow, Russia
Lapin A.S. – Laboratory Research Assistant. Contacts: 1, pl. Akademika Kurchatova, Moscow, Russia, 123182. Tel.: +7 (915) 129-54-14; e-mail:
Blandinsky V.Yu. – Deputy Head of International Affairs – Scientific Secretary, Cand. Sci. (Tech.).
Vnukov R.A. – Laboratory Research Assistant.
Kolesov V.V. – Ph.D., Head of the laboratory, Cand. Sci. (Phys.-Math.).
Nevinitsa V.A. – Head of the Department, Cand. Sci. (Tech.).
Rodionova E.V. – Senior Researche.
; Kuzenkova D.S. – Junior Researcher.
Fomichenko P.A. – Deputy Head of the Complex.
Tsybulsky S.V. – Senior Researcher.
Abstract
The article discusses the methodological features of calculating the cadmium ratio using Monte Carlo programs. The cadmium ratio is a physical value that characterizes the ratio of the thermal neutron flux to the total neutron flux at a given point. It plays an important role in nuclear physics and is used to determine the spectrum of neutrons in various media. The article describes three methods for calculating functionals, such as the cadmium ratio, in a limited volume relative to the entire model using the Monte Carlo method. The first is the direct calculation method, which implies the direct calculation of the necessary quantities in the framework of a given geometry and conditions. The second is the method of using the value grid. However, it was not used to calculate the cadmium ratio, since in test calculations it showed a significant increase in calculation time compared to the direct method when achieving similar accuracy. The third method that has been applied is a piecemeal calculation. It consists in the following. At the first stage, the neutron flux on the surface of the sphere surrounding the area of interest is calculated, taking into account the energetic distribution of neutrons by groups. At the second stage, the problem with an external source determined by the neutron flux on the surface is solved inside this sphere, and the required functional, the cadmium ratio, is calculated. This method makes it possible to reduce the calculation time compared to other methods considered while maintaining high accuracy of the results. The results obtained are in good agreement with each other, as well as with the experimental data obtained at the BFS-93 assembly.
Keywords
BFS-1, BFS-93, cadmium coefficient, Monte Carlo method, piecemeal calculation method, gold foil, cadmium case
Article Text (PDF, in Russian)
UDC 621.039
Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2024, no. 3, 3:4