SURFACE TEMPERATURE MEASUREMENTS WITH THERMO-ELECTRIC MATERIALS
Abstract
A study was made of the errors in surfacetemperature measurements made with a thermocouple (TC), wouples, *High temperature research, Reliability, Instrumentation, Aero dynamic heating, Simulation, Surfaces, Tempera ture, Heat transfer, Thermal conductivity, Noise, Vibration, Calibration, Stability, Materials, Wire, Copper alloys, Nickel alloys, Platinum alloys, Rhodium alloys, Chromium alloys, Aluminum alloys, Bibliography, Coatings.A study was made of the errors in surfacetemperature measurements made with a thermocouple (TC), when both TC wires and surface are exposed to radiant energy. The errors arise from the net heat transfer at the TC junction, and the qulity and stability (change in calibration) of the TC materials. The response of surface TC's to transient heating was studied. For a single specimen thickness, transient response is greater for large TC wire diameter during the initial transient heating period but becomes independent of TC wire diameter when the heat flux rate reaches steady state. The magnitude of errors arising from instability, hich is independent of the quality of TC materials, depends upon the exposure condition and duration. The calibration of commercial thermocouples, whether noble metal or base metal, will probably change less than 1 F after exposure at less than 1000 F in air for 1000 hours. Failure of TC's due to vibration at 40 cps and 2 to 3g acceleration for up to 4 hours is unlikely up to temperatures of about 1300 F. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1962
- Accession Number
- AD0286098
Entities
Organizations
- SRI International