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Published on: December 12, 2013
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A Summary of Heat-Flux Sensor Calibration Data.
A V Murthy1, G T Fraser2, D P DeWitt2
1Aero-Tech, Inc., Hampton, VA.
Summary
This study statistically evaluated heat-flux sensor responsivity, finding agreement within 3% between NIST and customer calibrations for over half the sensors tested. This indicates encouraging results despite variations in calibration methods and sensor types.
Area of Science:
- Metrology
- Radiometry
- Sensor Technology
Background:
- Accurate heat-flux measurement is critical in various scientific and engineering applications.
- Standardized calibration procedures are essential for reliable sensor performance.
- Electrical substitution radiometers (ESRs) serve as primary standards for radiometric measurements.
Purpose of the Study:
- To statistically evaluate the responsivity of customer-supplied heat-flux sensors.
- To compare calibration results obtained by NIST with those provided by customers.
- To assess the agreement between different calibration techniques and sensor types.
Main Methods:
- Calibration of heat-flux sensors using an electrical substitution radiometer (ESR) as a transfer standard up to 5 W·cm(-2).
- Statistical analysis of responsivity data from circular-foil and thermopile heat-flux sensors.
- Comparison of responsivity values measured by NIST and by the sensor customers.
Main Results:
- Over 50% of the tested heat-flux sensors showed agreement within 3% between NIST and customer responsivity measurements.
- The study encompassed circular-foil and thermopile sensor types.
- Measurements were performed up to a heat flux of 5 W·cm(-2).
Conclusions:
- The agreement between NIST and customer calibration results is encouraging, despite variations in customer calibration techniques and sensor types.
- The findings support the reliability of heat-flux sensor calibrations when using appropriate transfer standards.
- Further investigation may be warranted to explore the factors contributing to discrepancies in the remaining sensors.
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