Izvestiya vuzov. Yadernaya Energetika

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

Modernization of Subchannel Thermal-Hydraulic Code SC-INT

12/10/2025 2025 - #04 Thermal physics and thermal hydraulics

Vertikov E.A. Zaporzhin K.V. Oleksyuk D.A. Khamaza V.A. Khudykin A.M. Glazov M.A. Morozkin O.N.

DOI: https://doi.org/10.26583/npe.2025.4.03

UDC: 621.039.534...23

The article presents the main results of the cycle of works on modernization of the source code of the SC-INT computer program designed for subchannel thermal-hydraulic calculations of the cores of water-cooled nuclear reactors. The mathematical description of the program is briefly given, including the method of allocation of elementary volumes in space, the discrete analog of the basic conservation laws forming the system of nonlinear equations, as well as the method of its solution. The path passed on the internal modernization of the program is described in detail: ejection of obsolete Fortran programming language constructions, transition to the structure-oriented approach of writing the source code, development of modular architecture, as well as the implementation of an alternative numerical algorithm for solving the basic system of nonlinear equations using the PETSc library. As an example of SC-INT program capabilities, which appeared after the above described modernizations, the results of thermal-hydraulic calculation in the fine mesh approximation of a full-scale core of VVER-1000 reactor, assembled from fuel assemblies of different design: with and without installed grids-intensifiers of “Vikhr” and “Progonka” type. It is demonstrated that the residuals on the main coolant parameters achieved in the simulation of full-scale core modeling match in order with the corresponding values characteristic for the calculations of small-scale experimental models of fuel assemblies. Thermal-hydraulic calculations of full-scale cores in the subchannel approximation opens the possibility for the development of coupled program complexes designed for improved estimation of the parameters of multiphysics processes in the cores of water-cooled nuclear reactors.

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program architecture subchannel analysis control volume method thermal-hydraulic calculation core VVER

Link for citing the article: Vertikov E.A., Zaporzhin K.V., Oleksyuk D.A., Khamaza V.A., Khudykin A.M., Glazov M.A., Morozkin O.N. Modernization of Subchannel Thermal-Hydraulic Code SC-INT. Izvestiya vuzov. Yadernaya Energetika. 2025, no. 4, pp. 29-43; DOI: https://doi.org/10.26583/npe.2025.4.03 (in Russian).

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