CSNI0051 FIX-II/5052.

1. NAME OR DESIGNATION:  FIX-II/5052.

3. DESCRIPTION OF TEST FACILITY

The FIX-II facility is a volume scaled 1:777 representation of a Swedish BWR with external pumps. The pressure vessel contains a 36 rod full length bundle and a
spray condenser at the top to allow steady state operation. The downcomer, bypass channels and guide tube volumes are represented by external piping. The intact loop represents three of the four external reactor loops. The broken loop is constructed such that both guillotine breaks and split breaks may be simulated. The facility is equipped with ADS-simulation, but no ECCS injection are included. The FIX-II loop is also suited to investigate response of pump trips and MSIV closures in internal pump reactors.

4. DESCRIPTION OF TEST

LOCA test No. 5052 simulated a guillotine break in one of the four main recirculation lines. The total break area, equally divided in the two discharge lines, was 200 per cent of the scaled down pipe area of the reactor. The initial power of the 36-rod bundle in the FIX loop was 3.36 MW, corresponding to the hot channel power of the reactor.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM: EXPERIMENTAL LIMITATIONS OR SHORTCOMINGS

6. PHENOMENA TESTED

Collapsed level behaviour in downcomer; core thermal hydraulics; void collapse and temperature distribution during pressurization; critical power ratio.

7. UNUSUAL FEATURES: SPECIAL FEATURES OF EXPERIMENT

8. RELATED OR AUXILIARY PROGRAMS: COUNTERPART EXPERIMENTS

10. REFERENCES

- L. Nilsson, et. al.:
FIX-II LOCA Blowdown and Pump Trip Heat Transfer Experiments,
Experimental Results from Pump Trip Experiments of Test Groups
Nos. 1, 2, 8 (STUDSVIK/NR-83/324)

- Lars NILSSON et al:
FIX-II - LOCA Blowdown And Pump Trip Heat Transfer Experiments
Experimental results from LOCA test No. 5052 (STUDSVIK/NR-83/323, 1983)
- L. Nilsson, P.-A. Gustavsson:
FIX-II LOCA Blowdown and Pump Trip Heat Transfer Experiments,
Description of Experimental Equipment, Part 1, 2 and 3
(STUDSVIK/NR-83/238, February 1983)
- L. Nilsson, et. al.:
FIX-II LOCA Blowdown and Pump Trip Heat Transfer Experiments,
Topical Report of Phase 4:
Results of Static Dryout Measurements in the 36-Rod Bundle
(STUDSVIK/NR-83/274, 1983)
- L. Nilsson:
FIX-II LOCA Blowdown and Pump Trip Heat Transfer Experiments
Summary Report for the second experimental period (STUDSVIK/NR-85/42)
- R. Persson, L. Nilsson and L. Gustafson:
FIX-II Transient Dryout Tests
Summary Report (STUDSVIK/NP-86/35, March 1986)
- J. Eriksson:
ICAP, Assessment of RELAP5/MOD2, Cycle 36.04 against FIX-II
Guillotine Break Experiment No 5061 (STUDSVIK/NP-86/109, October 1986)
- L. Nilsson:
Transfer of data from FIX-II experiments to OECD/NEA's Databank
for the CSNI Code Validation Matrix (NS-92/58, September 1992)

11. TEST DESIGNATION:  5052

15. ESTABLISHMENT

   LARS NILSSON, Per-Aake GUSTAFSSON, Lennart GUSTAFSON,
   Rajmund JANCZAK, Ingrid OESTERLUNDH

   Swedish Nuclear Power Inspectorate

CCVM data        mag tapeFIX-II LOCA test 5052 results              CVMTP