Authors & Affiliations
Avvakumov A.V., Mitenkova E.F., Novikov N.V.
Nuclear Safety Institute of the Russian Academy of Sciences, Moscow, Russia
Mitenkova E.F. – Head of Laboratory, Cand. Sci. (Phys.-Math.), Nuclear Safety Institute of Russian Academy of Sciences.
Novikov N.V. – Senior Researcher, Cand. Sci. (Phys.-Math.), Nuclear Safety Institute of Russian Academy of Sciences.
A calculation analysis of the response of ionization chambers located in the concrete protection of the VVER reactor to the neutron flux distribution within the core is a rather complex problem of neutron transport. Here there are the multiple attenuation of neutron flux, leaked from the core and strong an-isotropy of neutron scattering. This task relates to the reactor protection problem, therefore, the accurate models with the Monte Carlo calculation methods are necessary. In this paper, the neutron transport out of the core is modeled using the MCNP5 code in two-dimensional geometry, taking into account the real geometry of the VVER-1000 core, the baffle and location of the neutron flux detectors. As a result of the Monte Carlo calculations, the response weight functions of individual fuel assemblies for several ionization chambers were obtained.
nuclear reactor, core, VVER, baffle, lateral ionization chambers, ex-core neutron flux detector, response weight functions, Monte Carlo method
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