Analysis of multiple-tube ruptures in both steam generators for the Three Mile Island-1 pressurized water reactor
The operator guidelines were followed for both transients described. Both transients resulted in SG overfill and the tube-rupture flow did not terminate in either transient. The following statements can be deducted from the results of the calculations: the tube-rupture flow could not be stopped for either case during 2600 s (43 min) of transient time; each accident scenario resulted in SG overfill; both SGs overfilled by 1600 s (27 min) and 1800 s (30 min) for Cases 1 and 2, respectively; conditions for isolation of the SGs were not reached; and core subcooling was not lost in either case but the upper head was voided in Case 2. Comparison of the cooldown rates in the two cases after 1200 s (20 min) shows that these rates are equal (i.e., restart of the RCPs did not change the primary-system cooldown rate). However, in Case 2, a steam bubble was formed in the upper head, which did not disappear during the simulated time. One of the immediate actions in the guidelines was to fill both SGs to 95% level. This step was almost unnecessary because the tube-rupture flow was large enough that the 15.4 - mK/s (100 - /sup 0/F h) cooldown-rate limit was exceeded and AFW could not be injected. Also, the guidelines did not address the SG overfill issue.
- Research Organization:
- Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 5040153
- Report Number(s):
- LA-UR-85-946; CONF-851007-6; ON: TI85010105
- Resource Relation:
- Conference: 3. international meeting on reactor thermal hydraulics, Newport, RI, USA, 15 Oct 1985
- Country of Publication:
- United States
- Language:
- English
Similar Records
Assessment of RELAP5/MOD3.1 with the LSTF SB-SG-06 experiment simulating a steam generator tube rupture transient
SCDAP/RELAP5 Evaluation of the Potential for Steam Generator Tube Ruptures as a Result of Severe Accidents in Operating PWRs
Related Subjects
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
THREE MILE ISLAND-1 REACTOR
TRANSIENTS
LOSS OF COOLANT
REACTOR OPERATION
RUPTURES
STEAM GENERATORS
TUBES
ACCIDENTS
BOILERS
ENRICHED URANIUM REACTORS
FAILURES
OPERATION
POWER REACTORS
PWR TYPE REACTORS
REACTOR ACCIDENTS
REACTORS
THERMAL REACTORS
VAPOR GENERATORS
WATER COOLED REACTORS
WATER MODERATED REACTORS
220900* - Nuclear Reactor Technology- Reactor Safety
210200 - Power Reactors
Nonbreeding
Light-Water Moderated
Nonboiling Water Cooled