Los Alamos PWR decay-heat-removal studies. Summary results and conclusions

Technical Report · Sat Mar 01 04:00:00 EST 1986

DOI:https://doi.org/10.2172/6253073· OSTI ID:6253073

Boyack, B E; Henninger, R J; Horley, E; Lime, J F; Nassersharif, B; Smith, R

The adequacy of shutdown-decay-heat removal in pressurized water reactors (PWRs) is currently under investigation by the Nuclear Regulatory Commission. One part of this effort is the review of feed-and-bleed procedures that could be used if the normal cooling mode through the steam generators were unavailable. Feed-and-bleed cooling is effected by manually activating the high-pressure injection (HPI) system and opening the power-operated relief valves (PORVs) to release the core decay energy. The feasibility of the feed-and-bleed concept as a diverse mode of heat removal has been evaluated at the Los Alamos National Laboratory. The TRAC-PF1 code has been used to predict the expected performance of the Oconee-1 and Calvert Cliffs-1 reactors of Bobcock and Wilcox and Combustion Engineering, respectively, and the Zion-1 and H.B. Robinson-2 plants of Westinghouse. Feed and bleed was successfully applied in each of the four plants studied, provided it was initiated no later than the time of loss of secondary heat sink. Feed and bleed was successfully applied in two of the plants, Oconee-1 and Zion-1, provided it was initiated no later than the time of primary system saturation. Feed and bleed in Calvert Cliffs-1 when initiated at the time of primary system saturation did result in core dryout; however, the core heatup was eventually terminated by coolant injection. Feed-and-bleed initiation at primary system saturation was not studied for H.B. Robinson-2. Insights developed during the analyses of specific plant transients have been identified and documented. 33 refs., 107 figs., 26 tabs.

• Research Organization: Los Alamos National Lab., NM (USA)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 6253073
• Report Number(s): NUREG/CR-4471; LA-10637-MS; ON: TI86008809
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
210200* -- Power Reactors
Nonbreeding
Light-Water Moderated
Nonboiling Water Cooled
42 ENGINEERING
420400 -- Engineering-- Heat Transfer & Fluid Flow
AFTER-HEAT REMOVAL
CALVERT CLIFFS-1 REACTOR
COMPARATIVE EVALUATIONS
DESIGN
ENERGY TRANSFER
ENRICHED URANIUM REACTORS
FLUID FLOW
HEAT TRANSFER
OCONEE-1 REACTOR
PERFORMANCE
POWER REACTORS
PWR TYPE REACTORS
REACTORS
REMOVAL
RESEARCH PROGRAMS
ROBINSON-2 REACTOR
THERMAL REACTORS
WATER COOLED REACTORS
WATER MODERATED REACTORS
ZION-1 REACTOR