Izvestiya vuzov. Yadernaya Energetika

The peer-reviewed scientific and technology journal. ISSN: 0204-3327

Determining the Temperature Coefficient of Reactivity of the VVR-ts Reactor in the Operating Temperature Range

12/14/2022 2022 - #04 Physics and technology of nuclear reactors

Kochnov O.Yu. Pakholik D.A. Nikulin E.V. Kolesov V.V.

DOI: https://doi.org/10.26583/npe.2022.4.02

UDC: 621.039.516.25

The VVR ts research nuclear reactor is designed to perform a wide range of scientific and experimental work, such as: research in the field of radiation chemistry and solid state physics, radiation processing of materials, research in the field of radiation materials science, neutron activation and neutron structural analysis, biomedical research, etc.

The temperature coefficient of reactivity, which manifests itself when the moderator (coolant) temperature changes, is one of the most important reactor neutronic parameters. First of all, it is used in the calculation of the reactor reactivity margin. Previously, for the VVR ts reactor, the temperature coefficient of reactivity was determined in the course of experimental studies at the minimum controlled power level at relatively low moderator temperatures that do not correspond to the nominal values. This, in turn, affects the accuracy of the calculated estimate of the reactor reactivity margin.

The purpose of this work is to study the temperature coefficient of reactivity of the VVR ts reactor, which manifests itself when the temperature of its moderator changes in the operating temperature range. The paper presents the methodology and description of the experiment to determine the temperature coefficient of reactivity as well as the results of a computational study using the MCNP program. The obtained values of the temperature coefficient of reactivity are necessary for refining the model of the VVR ts reactor core during neutronic calculations and confirming the safe operation of the reactor.


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VVR ts reactor temperature effect of reactivity temperature coefficient of reactivity operational reactivity margin

Link for citing the article: Kochnov O.Yu., Pakholik D.A., Nikulin E.V., Kolesov V.V. Determining the Temperature Coefficient of Reactivity of the VVR-ts Reactor in the Operating Temperature Range. Izvestiya vuzov. Yadernaya Energetika. 2022, no. 4, pp. 19-27; DOI: https://doi.org/10.26583/npe.2022.4.02 (in Russian).