Izvestiya vuzov. Yadernaya Energetika

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

Actual Problems of Thermal-Hydraulic Modelling in Fast Neutron Reactors

6/05/2024 2024 - #02 Thermal physics and thermal hydraulics

Kuzina Yu.A. Sorokin A.P.

DOI: https://doi.org/10.26583/npe.2024.2.04

UDC: 536.24+621.039.553.34

The results of studies of hydrodynamics and heat transfer processes in fast neutron reactors are presented. Data on turbulent momentum transfer in rod bundles are analyzed. It is shown that the intensification of turbulent momentum transfer in the rod bundle channels is due to large-scale turbulent momentum transfer (secondary currents). The intensification of interchannel turbulent exchange in close lattices of rods is explained. A dependence is obtained for the dissimilarity coefficients of interchannel convective exchange forced by wire winding in bundles of rods. The methods and results of numerical modelling of thermal hydraulics using the Monte Carlo method, thermomechanical analysis of the temperature field in fuel rod assemblies during the campaign are presented. The results of modelling on a water model of temperature fields and the structure of coolant movement in the primary circuit of the reactor in various regimes are presented. A stable temperature stratification of the coolant was revealed in the peripheral zone of the upper chamber of the reactor above the side screens. It is shown that the process of boiling liquid metals in fuel assemblies has a complex structure, characterized by stable and pulsating regimes and a heat transfer crisis. The agreement between the results of experimental and numerical modelling is shown. A cartogram of the flow regimes of a two-phase flow of liquid metals in fuel rod assemblies has been constructed. The influence of the surface roughness of fuel elements on the boiling process and heat transfer during boiling of liquid metals is analyzed. Long-term cooling of a fuel assembly with a «sodium cavity» above the reactor core in accident regimes with boiling of liquid metals is shown. The objectives of further research are formulated.


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fast reactor reactor tank fuel rod assemblies hydrodynamics heat transfer experiment computational modelling turbulent transfer interchannel exchange coolant temperature stratification boiling regimes roughness two-fluid model

Link for citing the article: Kuzina Yu.A., Sorokin A.P. Actual Problems of Thermal-Hydraulic Modelling in Fast Neutron Reactors. Izvestiya vuzov. Yadernaya Energetika. 2024, no. 2, pp. 41-58; DOI: https://doi.org/10.26583/npe.2024.2.04 (in Russian).