Effect of partial blockages in simulated LMFBR fuel assemblies

Technical Report · Sat Dec 01 04:00:00 EST 1973

DOI:https://doi.org/10.2172/4357059· OSTI ID:4357059

Fontana, M H; Kress, T S; Parsly, T S; Thomas, D G; Wantland, J L

Experimental data on the effects of partlal blockages in simulated LMFBR rod bundles are reviewed and the results presented. Experiments performed in the ORNL Fuel Failure Mockup (FFM) with 13- and 24-channel inlet blockages in 19-rod sodium-cooled electrically heated rod bundles indicate that excessive temperatures do not occur as a result of the blockages. Similar experiments with 6-channel non-heat-generating blockages in the heated zone of the rod bundle indicate local temperature increases of approximates 100 deg F at full flow and linear heat ratings of 10 kW/ft. Calculations of temperatures within heat- generating blockages indicate that, with more than one subchannel blocked over an infinite'' length, resulting temperatures are above the cladding limit. Results from experiments with the FFM water mockup showed local heat transfer variations with 6-, 12-, and 24-channel central blockages and with edge blockages extending over one-third of the total area of the rod bundle. For this latter case, reductions in heat transfer coefficient to one-third of the free-stream value were obseved. A simple representation of flow recirculation in the wake of a blockage indicates that a small recirculating flow significantly reduces temperatures in the wake zone. (auth)

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: US Atomic Energy Commission (AEC)
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-29-014646
• OSTI ID: 4357059
• Report Number(s): ORNL-TM--4324
• Country of Publication: United States
• Language: English

Related Subjects

*FFTF REACTOR-- FUEL ASSEMBLIES
*FUEL CHANNELS-- FLUID FLOW
*LMFBR TYPE REACTORS-- FUEL CHANNELS
COOLANT LOOPS
FLOW RATE
HEAT TRANSFER
LOSS OF FLOW
N77500* --Reactors--Power Reactors
Breeding
SIMULATION