CSNI0026 SEMISCALE/S-UT-1.

1. NAME OR DESIGNATION:  SEMISCALE/S-UT-1.

3. DESCRIPTION OF TEST FACILITY

The Semiscale Mod-2A system for this test consists of a pressure vessel with simulated reactor internals, including a 256-rod core with electrically powered rods and an external downcomer assembly; an intact loop with pressurizer, steam generator, and pump; and a broken loop with a steam generator, pump, and rupture assembly. The system also has emergency core coolant (ECC) from high- and low-pressure injection pumps for each loop; a coolant injection accumulator for the intact loop and a pressure suppression system with header, suppression tank, and steam supply system.

4. DESCRIPTION OF TEST

This test simulates a loss-of-coolant accident resulting from a 10% communicative break in the cold leg of a pressurized water reactor. The break size for this test was 0.228 sq.cm. which is volumetrically scaled to represent a 10% pipe break in a PWR. The Mod-2A system was configured to simulate a PWR with the capability to inject emergency core coolant (ECC) into the vessel upper head. However, for this test, no upper head ECC injection was used. The intact loop accumulator pressure was set at 2.76 MPa as is specified for upper head injection (UHI) plants.

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

6. PHENOMENA TESTED

Natural circulation in 1- and 2-phase flow; core thermohydraulics; 1- and 2-phase  pump behaviour.

7. UNUSUAL FEATURES: SPECIAL FEATURES OF EXPERIMENT

8. RELATED OR AUXILIARY PROGRAMS: COUNTERPART EXPERIMENTS

10. REFERENCES

- Kenneth E. Sackett, L. Bruce Clegg
  "Experiment Data Report for Semiscale MOD-2A Small Break Test   Series (Tests S-UT-1 and S-UT-2)"
  NUREG/CR-2176 and EGG-2108, July 1981

- G.G. Loomis:
  Summary Report Semiscale Mod-2A Heat Loss Characterization Test Series
  EGG-SEMI-5448 (May 1981)
- E.M. Feldman and D.J. Olson:
  Semiscale Mod-1 Program and System Description for the Blowdown
  Heat Transfer Tests (ANCR-1230, August 1975)
- R.T. French:
  An Evaluation of Piping Heat Transfer Piping Flow Regimes,
  and Steam Generator Heat Transfer for the Semiscale Mod-1
  Isothermal Tests (ANCR-1229, August 1975)
- M.T. Leonard:
  RELAP5 Standard Model Description for the Semiscale Mod-2A System
  EGG-SEMI-5692 (December 1981)
- D.W. Golden:
  Steady State Control Model for the Standard RELAP5 Semiscale
  Mod-2A System Model
  RE-A-82-023 (April 1982)
- G.G. Loomis:
  Summary of the Semiscale Program (1965-1986)
  NUREG/CR-4945 - EGG-2509 (July 1987)
- John S. Martinelli:
  "Semiscale Loss-of-Power Test Results"
  11th Water Reactor Safety Research Information Meeting,
  October 24-28, 1983
  ECC-M-22283 Preprint
- L.J. Ball et al.:
  Semiscale Program Description (TREE-NUREG-1210, May 1987)
- J.E. Blakeley, R.G. Hanson, D.J. Shimeck:
  "Quick Look Report for Semiscale Mod-2A Test S-UT-1"
  EGG-SEMI-5331, January 1981
- M.T. Leonard:
  "Posttest RELAP5 Simulation of the Semiscale S-UT Series Experiments"
  EGG-SEMI-5622, October 1981

11. TEST DESIGNATION:  S-UT-1

15. ESTABLISHMENT

      Idaho National Engineering Laboratory
      Idaho Falls, Idaho, U.S.A.

CCVM data        mag tape              (TOTAL:    4,264,000 bytes)  CVMTP
CCVM data        mag tapeCurrent                     45,120         CVMTP
CCVM data        mag tapeComputed parameters        285,760         CVMTP
CCVM data        mag tapeDensity                    334,080         CVMTP
CCVM data        mag tapeForce                      152,000         CVMTP
CCVM data        mag tapeFlows                      273,600         CVMTP
CCVM data        mag tapeDifferential pressure      887,360         CVMTP
CCVM data        mag tapePressure                   225,600         CVMTP
CCVM data        mag tapePower                       60,160         CVMTP
CCVM data        mag tapeRotational speed            30,080         CVMTP
CCVM data        mag tapeTemperature              1,910,080         CVMTP
CCVM data        mag tapeVoltage                     60,160         CVMTP