Metal thermocouple correction methodology and evaluation (ECS-2C/ECS-2B test series)
Abstract
The metal thermocouple correction methodology and evaluation experiments were designed and performed to investigate downflow dryout in a heated ribbed vertical annulus. Subsequent experiments were performed in the same facility to investigate convective heat transfer under air/water downflow conditions. Under these conditions (greater than 40 K) azimuthal temperature variations were observed in the skin temperature measured using Type K thermocouples. The physical mechanisms causing the azimuthal variations in the thermocouples have not been identified. A methodology has been developed and evaluated for removing these effects. An uncertainty analysis has been performed to estimate the uncertainties resulting from application of the methodology. However, it is recommended that this methodology not be applied to the individual thermocouples unless a viable physical mechanism is identified to explain the observed thermocouple responses.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- June 1991
- Bibcode:
- 1991STIN...9213419A
- Keywords:
-
- Cooling Systems;
- Flow Velocity;
- Heat Transfer;
- Reactor Design;
- Temperature Measurement;
- Thermocouples;
- Aluminum;
- Calibrating;
- Ceramics;
- Correction;
- Covariance;
- Data Acquisition;
- Electric Fields;
- High Temperature;
- Magnetic Fields;
- Instrumentation and Photography