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International Journal of Thermophysics

, Volume 36, Issue 12, pp 3310–3319 | Cite as

Comparison of Blackbody Sources for Low-Temperature IR Calibration

  • S. Ljungblad
  • M. Holmsten
  • L. E. Josefson
  • P. Klason
Article
  • 217 Downloads

Abstract

Radiation thermometers are traditionally mostly used in high-temperature applications. They are, however, becoming more common in different applications at room temperature or below, in applications such as monitoring frozen food and evaluating heat leakage in buildings. To measure temperature accurately with a pyrometer, calibration is essential. A problem with traditional, commercially available, blackbody sources is that ice is often formed on the surface when measuring temperatures below \(0\,{}^{\circ }\hbox {C}\). This is due to the humidity of the surrounding air and, as ice does not have the same emissivity as the blackbody source, it biases the measurements. An alternative to a traditional blackbody source has been tested by SP Technical Research Institute of Sweden. The objective is to find a cost-efficient method of calibrating pyrometers by comparison at the level of accuracy required for the intended use. A disc-shaped blackbody with a surface pyramid pattern is placed in a climatic chamber with an opening for field of view of the pyrometer. The temperature of the climatic chamber is measured with two platinum resistance thermometers in the air in the vicinity of the disc. As a rule, frost will form only if the deposition surface is colder than the surrounding air, and, as this is not the case when the air of the climatic chamber is cooled, there should be no frost or ice formed on the blackbody surface. To test the disc-shaped blackbody source, a blackbody cavity immersed in a conventional stirred liquid bath was used as a reference blackbody source. Two different pyrometers were calibrated by comparison using the two different blackbody sources, and the results were compared. The results of the measurements show that the disc works as intended and is suitable as a blackbody radiation source.

Keywords

Blackbody IR calibration Radiation thermometry 

References

  1. 1.
    L. Knazovicka, R. Strnad, in Proceedings of Ninth International Temperature Symposium (Los Angeles), Temperature: Its Measurement and Control in Science and Industry, vol. 8, ed. by C.W. Meyer. AIP Conference Proceedings, vol. 1552 (AIP, Melville, 2013), pp. 678–681Google Scholar
  2. 2.
    H.Y. Ko, B.J. Wen, S.F. Tsa, G.W. Li, Int. J. Thermophys. 30, 98 (2009)CrossRefADSGoogle Scholar
  3. 3.
    J. Hameury, B. Hay, J.R. Filz, Int. J. Thermophys. 26, 1973 (2005)CrossRefADSGoogle Scholar
  4. 4.
    STEEP 320 version 1.4, Manual, Virial, IncGoogle Scholar
  5. 5.
    Uncertainty Budgets for Calibration of Radiation Thermometers Below the Silver Point, CCT-WG5 on Radiation Thermometry, pp. 1–41 (2011). http://www.bipm.org/wg/CCT/CCT-WG5/Allowed/Miscellaneous/Low_T_Uncertainty_Paper_Version_1.71.pdf

Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • S. Ljungblad
    • 1
  • M. Holmsten
    • 1
  • L. E. Josefson
    • 1
  • P. Klason
    • 1
  1. 1.SP Technical Research Institute of SwedenBoråsSweden

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