Numerical analysis of a novel spacer grid in rod bundles of PWR

doi:10.7523/j.issn.2095-6134.2018.02.008

Abstract

Abstract: Spacer grid is an important part of fuel assembly in reactor. The AFA-2G/3G spacer with mixing vane supports rod bundles well and enhances the heat transfer, but it has a complex structure and difficult processing. A novel spacer grid with the rectangular longitudinal vortex generators (RLVGs) is designed to improve thermal-hydraulic characteristics of fuel assembly. Based on the standard k-ε model with the enhanced wall treatment, a three-dimensional numerical simulation of the novel spacer grid in the channel of PWR fuel rods is presented. The effects of Reynolds number and attack angle are investigated. Numerical results show that the second flow generated by LVGs spreads to the downstream region of spacer grid and improves the heat transfer. The spacer grids with RLVGs with attack angles of 60° and 45° result in almost equal heat transfer performances. However, the spacer grid with RLVGs with attack angle of 60° brings about more pressure drop in comparison with that of the 45° case. The present research on new fuel assembly has certain potential value for the engineering design.

Key words: fuel assembly, spacer grid, longitudinal vortex generator, CFD

CLC Number:

TL421+.1

LIANG Haoyu, WU Junmei. Numerical analysis of a novel spacer grid in rod bundles of PWR[J]. , 2018, 35(2): 200-208.

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