CSNI1003 PDHT-LP.

1. NAME OR DESIGNATION:  PDHT-LP.

3. DESCRIPTION OF TEST FACILITY

Water was heated to the desired temperature via a preheater with the flow monitored by turbine flow meters. The vertically mounted test section consisted of a 920mm long Nimonic 75 tube, 9.85mm ID and 14.0mm OD, which was surrounded by five concentric layers of polished nickel and 50mm of insulation to act as a heat shield and minimise heat losses. Two 36mm thick nickel-plated copper blocks were brazed to either end of the heated length, which acted as the hot patches. The position of the dry-out front was maintained upstream of the test section by heat transfer from the hot patches, which were instrumented with thermocouples to enable the heat fluxes to be evaluated, although only upflow tests (using the lower hot patch) were performed in this facility. The test section itself had a total of 39 thermocouples attached to the outer surface.

4. DESCRIPTION OF TEST

Both the 0.2Mpa and 0.4Mpa test series were performed at the same set of flow rates; 25, 50, 100 and 150kg/m2s. For the 0.2Mpa test series, inlet subcooling was varied over 21 - 46167C, whereas for the 0.4Mpa test series, inlet subcooling was varied over 28 - 50 deg.C.

5. EXPERIMENTAL LIMITATIONS OR SHORTCOMINGS

Low pressures only suitable for Large Break LOCA conditions. Upflow test data only.

6. PHENOMENA TESTED:  Post-dryout heat transfer.

7. SPECIAL FEATURES OF EXPERIMENT:  Provides steady state post-dryout heat transfer data.

10. REFERENCES

- G Costigan, J C Ralph and C D Wade:
  Steady State Heat Transfer Measurements Relevant to Reactor
  Reflood Conditions (AERE R 12561, February 1987)

- D Swinnerton, M L Hood and KC Pearson:
Steady State Post-Dryout at Low Quality  and Medium Pressure
AEEW-R2267, June 1988

11. TEST DESIGNATION

Low Pressure Post-Dryout Loop (Harwell).
A total of 73 upflow tests were performed over a range of inlet subcooling and flow rates, at pressures of 0.2 and 0.4MPa.

15. ESTABLISHMENT

   AEA Technology Harwell
   Oxfordshire OX11 ORA
   United Kingdom

CCVM PDHT_LP for Data 1 and 2 (457 KB)