A means for calibrating total heat flux gauges using a comparative (substitution) technique was established. An apparatus consisting of a reference radiometer, a stable infrared radiant heater capable of producing flux levels up to 3.7 W/sq cm, and a precision alignment mechanism was constructed. The reference radiometer was characterized by the Radiometric Physics Division at flux levels in the range 0.8 mW/sq cm to 0.9 W/sq cm. Its accuracy was found to be within 3 percent over this range which spans 3 orders of magnitude. As the radiometer is a highly linear thermocouple-based device having a self-calibration feature, this accuracy is expected to hold up to 4.2 W/sq cm, the upper limit of this device. Although the overall accuracy of calibrations performed in the new apparatus must still be established, it is expected to be within 3 to 5 percent.
Interim Report Federal Aviation Administration
- Pub Date:
- April 1990
- Heat Flux;
- Infrared Radiation;
- Instrumentation and Photography