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Title: CFD Simulations of a Flow Mixing and Heat Transfer Enhancement in an Advanced LWR Nuclear Fuel Assembly

Abstract

A computational fluid dynamics (CFD) analysis has been performed to investigate a flow-mixing and heat-transfer enhancement caused by a mixing-vane spacer in a LWR fuel assembly which is a rod bundle. This paper presents the CFD simulations of a flow mixing and heat transfer in a fully heated 5x5 array of a rod bundle with a split-vane and hybrid-vane spacer. The CFD prediction at a low Reynolds number of 42,000 showed a reasonably good agreement of the initial heat transfer enhancement with the measured one for a partially heated experiment using a similar spacer structure. The CFD simulation also predicted the decay rate of a normalized Nusselt number downstream of the split-vane spacer which agrees fairly well with those of the experiment and the correlation. The CFD calculations for the split vane and hybrid vane at the LWR operating conditions(Re = 500,000) predicted hot fuel spots in a streaky structure downstream of the spacer, which occurs due to the secondary flow occurring in an opposite direction near the fuel rod. However, the split-vane and hybrid-vane spacers are predicted to significantly enhance the overall heat transfer of a LWR nuclear fuel assembly. (authors)

Authors:
; ; ;  [1]
  1. Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Yuseong-Gu, Daejeon, Korea 305-353 (Korea, Republic of)
Publication Date:
Research Org.:
American Nuclear Society, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)
OSTI Identifier:
21229264
Resource Type:
Conference
Resource Relation:
Conference: 2007 LWR Fuel Performance Meeting / TopFuel 2007, San Francisco, CA (United States), 30 Sep - 3 Oct 2007; Other Information: Country of input: France; 12 refs; Related Information: In: Proceedings of the 2007 LWR Fuel Performance Meeting / TopFuel 2007 'Zero by 2010', 683 pages.
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; 11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; COMPUTERIZED SIMULATION; FLUID MECHANICS; FUEL ELEMENT CLUSTERS; FUEL RODS; HEAT TRANSFER; HYBRIDIZATION; NUCLEAR FUELS; NUSSELT NUMBER; REYNOLDS NUMBER

Citation Formats

In, Wang-Kee, Chun, Tae-Hyun, Shin, Chang-Hwan, and Oh, Dong-Seok. CFD Simulations of a Flow Mixing and Heat Transfer Enhancement in an Advanced LWR Nuclear Fuel Assembly. United States: N. p., 2007. Web.
In, Wang-Kee, Chun, Tae-Hyun, Shin, Chang-Hwan, & Oh, Dong-Seok. CFD Simulations of a Flow Mixing and Heat Transfer Enhancement in an Advanced LWR Nuclear Fuel Assembly. United States.
In, Wang-Kee, Chun, Tae-Hyun, Shin, Chang-Hwan, and Oh, Dong-Seok. Sun . "CFD Simulations of a Flow Mixing and Heat Transfer Enhancement in an Advanced LWR Nuclear Fuel Assembly". United States. doi:.
@article{osti_21229264,
title = {CFD Simulations of a Flow Mixing and Heat Transfer Enhancement in an Advanced LWR Nuclear Fuel Assembly},
author = {In, Wang-Kee and Chun, Tae-Hyun and Shin, Chang-Hwan and Oh, Dong-Seok},
abstractNote = {A computational fluid dynamics (CFD) analysis has been performed to investigate a flow-mixing and heat-transfer enhancement caused by a mixing-vane spacer in a LWR fuel assembly which is a rod bundle. This paper presents the CFD simulations of a flow mixing and heat transfer in a fully heated 5x5 array of a rod bundle with a split-vane and hybrid-vane spacer. The CFD prediction at a low Reynolds number of 42,000 showed a reasonably good agreement of the initial heat transfer enhancement with the measured one for a partially heated experiment using a similar spacer structure. The CFD simulation also predicted the decay rate of a normalized Nusselt number downstream of the split-vane spacer which agrees fairly well with those of the experiment and the correlation. The CFD calculations for the split vane and hybrid vane at the LWR operating conditions(Re = 500,000) predicted hot fuel spots in a streaky structure downstream of the spacer, which occurs due to the secondary flow occurring in an opposite direction near the fuel rod. However, the split-vane and hybrid-vane spacers are predicted to significantly enhance the overall heat transfer of a LWR nuclear fuel assembly. (authors)},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jul 01 00:00:00 EDT 2007},
month = {Sun Jul 01 00:00:00 EDT 2007}
}

Conference:
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