Design, development, and calibration of a thermocouple probe for the measurement of surface temperature distributions in rod clusters

Technical Report · Mon Oct 01 04:00:00 EDT 1973

OSTI ID:4939274

Stephens, M J; Birt, P J; Smith, S L; Pirie, M A.M.

A thermocouple probe developed for measuring surface temperature distributions in A.G.R. cluster heat transfer experiments is described. The probe is located on the bore of a pin and has nine sensing elements equally spaced around its circumference. Each sensing element is spring-loaded against the inner wall of the pin to ensure good thermal contact. The probe can be traversed over the length of a pin enabling temperature surveys to be speedily carried out. Proving tests were conducted to establish the magnitude of three sources of error due to bus-bar heating and conduction damping effects, and to provide a calibration if necessary. It is concluded that as a result of bus-bar heating effects the thermocouple probe records a temperature higher than the true pin bore temperature by 12% plus or minus 2% of the temperature difference between the bus-bar and pin. For a current of 300 amps, typical of the maximum used in cluster heat transfer tests, differences of 2 deg C plus or minus 0.3 deg C are implied. The above figure can be used as a calibration to correct probe temperature measurements. Other conclusions are that the presence of the thermocouple probe does not damp the circumferential temperature variation in the pin, and that the probe does accurately measure the latter provided correction is made for bus-bar heating effects. (UK)

• Research Organization: Central Electricity Generating Board, Berkeley (UK). Berkeley Nuclear Labs.
• Sponsoring Organization: Sponsor not identified
• NSA Number: NSA-29-028643
• OSTI ID: 4939274
• Report Number(s): RD/B/N--2514; RPC/HT/N--(73)19
• Country of Publication: United Kingdom
• Language: English

Related Subjects

AGR TYPE REACTORS
FUEL ELEMENT CLUSTERS
FUEL PINS
HEAT TRANSFER
N77300* --Reactors--Power Reactors
Non-breeding
Graphite Moderated
PERFORMANCE TESTING
PROBES
SPATIAL DISTRIBUTION
SURFACES
TEMPERATURE MEASUREMENT
THERMOCOUPLES