Izvestiya vuzov. Yadernaya Energetika

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

Selecting a Turbulence Model for Calculating the Temperature Profile at the Surface of VVER-1000 Fuel Assemblies in the NPP Spent Fuel Pool

3/18/2021 2021 - #01 Thermal physics and thermal hydraulics

Voronina A.V. Pavlov S.V.

DOI: https://doi.org/10.26583/npe.2021.1.08

UDC: 621.039.546.8

The article focuses on the problem of selecting a turbulence model to simulate natural convection at the surface of VVER-1000 fuel assemblies unloaded from the reactor by computational fluid dynamics (CFD) methods. The turbulence model is selected by comparing the calculated data obtained using the Ansys Fluent software package with the results of experimental studies of natural convection at the surface of a heated vertical plate immersed in water, which in the first approximation simulates the lateral face of a VVER-1000 fuel assembly. The most widely-used in engineering practice two-parameter semi-empirical models of turbulence, k-ε and k-ω, are considered. The calculated and experimental data were compared on the excess temperature of the plate surface and on the water temperature profiles in the turbulent boundary layer for convection modes with the Rayleigh number from 8⋅1013 to 3.28⋅1014. It is shown that the best agreement with experimental data with an average deviation not exceeding ~ 8- is provided by the RNG k-ω model, which is recommended to be used in modeling natural convection at the fuel assembly surface.


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natural convection model turbulence laminarity fuel assembly temperature Ansys Fluent