Investigation of Swirling Flow in Rod Bundle Subchannels Using Computational Fluid Dynamics

Conference · Sat Jul 01 04:00:00 EDT 2006

OSTI ID:20995475

Holloway, Mary V ^[1]; Beasley, Donald E ^[2]; Conner, Michael E ^[3]

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1. United States Naval Academy, 117 Decatur Road, Annapolis, MD 21402-5018 (United States)
2. Clemson University, Clemson, S.C. 29634 (United States)
3. Westinghouse Nuclear Fuel (United States)

The fluid dynamics for turbulent flow through rod bundles representative of those used in pressurized water reactors is examined using computational fluid dynamics (CFD). The rod bundles of the pressurized water reactor examined in this study consist of a square array of parallel rods that are held on a constant pitch by support grids spaced axially along the rod bundle. Split-vane pair support grids are often used to create swirling flow in the rod bundle in an effort to improve the heat transfer characteristics for the rod bundle during both normal operating conditions and in accident condition scenarios. Computational fluid dynamics simulations for a two subchannel portion of the rod bundle were used to model the flow downstream of a split-vane pair support grid. A high quality computational mesh was used to investigate the choice of turbulence model appropriate for the complex swirling flow in the rod bundle subchannels. Results document a central swirling flow structure in each of the subchannels downstream of the split-vane pairs. Strong lateral flows along the surface of the rods, as well as impingement regions of lateral flow on the rods are documented. In addition, regions of lateral flow separation and low axial velocity are documented next to the rods. Results of the CFD are compared to experimental particle image velocimetry (PIV) measurements documenting the lateral flow structures downstream of the split-vane pairs. Good agreement is found between the computational simulation and experimental measurements for locations close to the support grid. (authors)

• Research Organization: The ASME Foundation, Inc., Three Park Avenue, New York, NY 10016-5990 (United States)
• OSTI ID: 20995475
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
ACCIDENTS
COMPUTERIZED SIMULATION
FLUID MECHANICS
FUEL ELEMENT CLUSTERS
HEAT TRANSFER
IMAGES
IMPINGEMENT
PITCHES
PWR TYPE REACTORS
RODS
TURBULENCE
TURBULENT FLOW
VANES
VELOCITY