EDN: ZKPUUZ
Authors & Affiliations
Anfimov A.M., Kirilov I.N., Timin D.A.
Afrikantov Experimental Design Bureau for Mechanical Engineering, Nizhny Novgorod, Russia
 
Anfimov A.M. – Head of Group, Department for Physical and Thermal-Hydraulic Analyses of Stationary Reactor Plants; 
 Kirilov I.N. –   Design Engineer Category 1st, Department for Physical and Thermal-Hydraulic Analyses of Stationary Reactor Plants. Contacts: 15, Burnakovsky proezd, Nizhny Novgorod, Russia, 603074. Tel.: +7 (831) 246-94-40; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
  Timin D.A. –  Design Engineer Category 3rd, Department for Physical and Thermal-Hydraulic Analyses of Stationary Reactor Plants. 
Abstract
The paper  presents the methodological approach to and results of the computational  analysis of a fuel assembly flow section blockage design-basis accident (DBA)  in a sodium-cooled fast reactor, with errors and uncertainties taken into  account.
In compliance with NP-18-05 “Requirements for the Contents of the Safety  Analysis Report for Nuclear Plants with Fast Neutron Reactors,” a fuel assembly  flow section blockage design-basis accident is to be considered. Since the  accident under consideration is of a design-basis type, a conservative approach  is used to do the accident analysis, which is determined by NP-001-15.
The goal of a DBA analysis is to confirm that DBA acceptance criteria  are not exceeded. For this purpose, conservative safety parameter values are  compared with the accepted criteria. The conservative value of the calculated  parameter is determined by a Monte-Carlo-method-based approach that allows  factoring in calculational errors and uncertainties.
The computational analysis of the main processes under accident  conditions involving complete blockage of the flow section in one fuel assembly  is conducted using the certified SOCRAT-BN code.
The computational analysis results show that the conservative values  determined for the reactor parameters important to safety, with account of the  errors and uncertainties, do not exceed the acceptance criteria set for the DBA  under consideration.
Keywords
error,  uncertainty, safety analysis, design-basis accident (DBA), sodium-cooled fast  reactor, sodium, flow section blockage accident, fuel assembly (FA), fuel pin,  sodium boiling, fuel meltdown
Article Text (PDF, in Russian)
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UDC 532.57, 536.24, 621.039.5
 Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2025, no. 2, 2:19