Nuclear Physics and Atomic Energy

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Nuclear Physics and Atomic Energy

  ISSN: 1818-331X (Print), 2074-0565 (Online)
  Publisher: Institute for Nuclear Research of the National Academy of Sciences of Ukraine
  Languages: Ukrainian, English
  Periodicity: 4 times per year

  Open access peer reviewed journal


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Nucl. Phys. At. Energy 2022, volume 23, issue 4, pages 245-254.
Section: Atomic Energy.
Received: 01.11.2022; Accepted: 30.12.2022; Published online: 6.02.2023.
PDF Full text (en)
https://doi.org/10.15407/jnpae2022.04.245

Long-term temperature dynamics at the peripherals on nuclearly hazardous clusters of fuel-containing materials located in room 305/2 of the "Shelter" object before and after new safe confinement installation into a design position

O. V. Mykhailov1,*, M. V. Saveliev1,2, R. L. Godun1, V. V. Àvgustov1

1 Institute for Safety Problems of Nuclear Power Plants, National Academy of Sciences of Ukraine, Chornobyl, Kyiv region, Ukraine
2 Institute of Mathematical Machines and Systems Problems, National Academy of Sciences of Ukraine, Kyiv, Ukraine


*Corresponding author. E-mail address: o.mikhailov@ispnpp.kiev.ua

Abstract: A brief overview of data of automated temperature monitoring systems at the periphery of nuclearly hazardous clusters of fuel-containing materials (FCM NHC) and analytical materials regarding the study of its dynamics at various monitoring points before and after installation of New Safe Confinement (NSC) into its design position, is presented. The characterization of revealed dominant trends in temperature time characteristics underway in the observation period from 1991 to 2015 and the reasons influencing their formation at various distances from FCM NHC boundaries in room 305/2, are addressed. The importance of the work of an expert research system (ERS), which functionally supplemented the existing nuclear safety monitoring system (NSMS) of CHNPP "Shelter" Object (SO) installed instead of decommissioned information and measuring system (IMS "Finish") and other autonomous FCM monitoring systems, is highlighted. A critical analysis of the state of current temperature monitoring around the FCM clusters is provided, and a conclusion about the need to improve the existing monitoring network is made.

Keywords: Chornobyl NPP, "Shelter" Object, New Safe Confinement, nuclearly hazardous clusters, fuel-containing materials, temperature, automated monitoring system.

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