Experimental Investigations of the Coolant Flow in the Fuel Assembly of the Fissile Core of the Reactor of a Small Nuclear Power Plant

• Published in: Journal of engineering physics and thermophysics 2022-11, Vol.95 (6), p.1479-1488
• Main Authors: Dmitriev, S. M., Dobrov, A. A., Doronkov, D. V., Doronkova, D. S., Pronin, A. N., Polunichev, V. I., Ryazanov, A. V., Khrobostov, A. E.
• Format: Article
• Language: English
• Subjects: Analysis; Assembly; Casing; Classical Mechanics; Complex Systems; Computational fluid dynamics; Coolants; Engineering; Engineering Thermodynamics; Experimental nuclear reactors; Flow distribution; Flow velocity; Fluid dynamics; Fuels; Heat and Mass Transfer; Industrial Chemistry/Chemical Engineering; Mathematical models; Nuclear energy; Nuclear fuel elements; Nuclear power plants; Nuclear reactors; Reactor cores; Thermodynamics; Velocity distribution
• ISSN: 1062-0125; 1573-871X
• DOI: 10.1007/s10891-022-02616-6

The results are presented of experimental investigations of the coolant flow in a bundle of fuel elements of a fuel assembly of a RITM-type reactor of a small nuclear power plant. The goal of this work is to investigate the redistribution of the field of axial and transverse velocities of the flow, and also the axial coolant flow downstream of a plate-type spacer grid of a fuel assembly. To achieve the set goal, a number of experiments were conducted in an aerodynamic research stand on a scaled model of a bundle of fuel elements of a fuel assembly with plate-type spacer grids. We selected a region covering a third of the entire cross section of the model and including all standard regular cells and cells adjacent to the casing, the stiffener angle and the central displacer pipe as a region to be investigated. The coolant flow pattern is represented by cartograms of transverse and axial velocity distribution, and also by dependence diagrams of distribution of axial velocities and coolant flow rates through characteristic cell types. The experimental results can be used for engineering feasibility demonstration of design solutions in designing RITM-type reactor fissile cores. The obtained experimental database on coolant flow in cassette-type fuel assemblies can be used for verification of advanced CFD (computational fluid dynamics) programs (of both foreign and domestic development) and programs of cellwise thermohydraulic calculation of fissile cores in proving a reliability of their thermal performance.