Using Equalizing Grids to Reduce Flow Unevenness in the Layout of the Active Zone of a Nuclear Reactor

Abstract

The article examines the effect of the equalizing grille design on the hydrodynamics of the flow in the inlet section of the aerodynamic layout of the nuclear reactor core. The results of numerical simulation of flow hydrodynamics using stationary averaged Reynolds equations, which are closed by a two-parameter k--ε turbulence model, are presented. As a result of the simulation, the values of the hydraulic resistance coefficient of the leveling grid and the local values of static pressure on the periphery of the model in the vicinity of the leveling grid under different flow conditions were determined. The effect of the grating on the magnitude of the flow velocity unevenness formed by the design of the supply path of the aerodynamic layout is shown, and an assessment of the effectiveness of axial velocity profile alignment is presented. The analysis of the flow and local effects of uneven static pressure distribution in the vicinity of the leveling grid is carried out. The effects of the design of the leveling grid on the formation of the flow, the distribution of static pressure at the periphery, and the value of the average static pressure in the sections before and after the grid for various flow modes are shown. The calculation method is validated using reference and experimental data obtained on an aerodynamic model. The deviation of the simulation results from the reference data and physical experiments does not exceed 10 %

Please cite this article in English as:

Kislov A.S., Markov P.V. Using equalizing grids to reduce flow unevenness in the layout of the active zone of a nuclear reactor. Herald of the Bauman Moscow State Technical University, Series Mechanical Engineering, 2026, no. 2 (157), pp. 121--136 (in Russ.). EDN: QCJCUY

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