The results of tests of the water mixing efficiency and the pressure drop in a channel with VVER model fuel assemblies equipped with modernized mixing grids of five types are presented. To evaluate the grid efficiency, experiments were performed with assemblies equipped with mixing grids of two types: ‘swirling around fuel rods’ and ‘sequential sweep.’ The main difference of the modernized grid from the two types of mixing grids is the arrangement of two paddles instead of one in each trihedral cell. The investigation was conducted on the Trasser facility by feeding into the flow in front of the grids a fluid tracer and determining its concentration in selected cells of the assembly. It is shown that equipping the VVER model fuel assemblies with a modernized grid of the second type instead of the grid of the ‘sequential sweep’ type appreciably increases the efficiency of mixing of the coolant with almost identical coefficients of hydraulic resistance.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
S. S. Borodin, S. M. Dmitriev, N. A. Legchanov, and A. E. Khrobostov, “Computational and experimental study of the mass transfer of coolant flow in TVSA of VVER type reactors when using mixing grids,” in: 6th Sci. Techn. Conf. on Safety of NPP with VVER, Podolsk, May 26–30, 2009, OKB Gidropress, Report 128.
R. S. Pometko and Yu. F. Selivanov, “Results of studies of crisis of heat transfer and mixing of coolant for VVER reactors.” in: 3rd Sci. Techn. Conf. on Safety of NPP with VVER, May 26–30, 2003, OKB Gidropress, Vol. 5, pp, 153–162.
A. V. Ivanov, I. S. Senin, S. I. Tsirin, et al., Patent No. 2581620 S1, “Structure of a plate-like grid for a fuel assembly,” Byull. Izobret. Polezn. Modeli, No. 11 (2016 ) (electronic version).
S. S. Borodin, S. M. Dmitriev, M. A. Legchanov, and A. E. Khrobostov, “Investigations of the mixing efficiency and mass transfer of coolant flow in TVSA of VVER reactors when using swirl-type mixing grids,” in: Thermohydraulic Aspects of the Safety of Cores Cooled by Water and Liquid Metals, Obninsk, Oct. 15–17, 2008, GNTs RF – FEI, pp. 96–104.
S. S. Borodin, S. M. Dmitriev, M. A. Legchanov, et al., “Investigations of local mass transfer of coolant in TVSA of VVER reactors when using sweep-type mixing grids,” ibid., pp. 105–110.
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Atomnaya Énergiya, Vol. 126, No. 3, pp. 156–160, March, 2019.
Rights and permissions
About this article
Cite this article
Perepelitsa, N.I. Coolant Mixing Intensity and Hydraulic Resistance of FA Mixing Grids. At Energy 126, 177–181 (2019). https://doi.org/10.1007/s10512-019-00533-1
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10512-019-00533-1