Thin Filament Pyrometry Field Measurements in a Medium-Scale Pool Fire

  • Zhigang Wang
  • Wai Cheong Tam
  • Jian Chen
  • Ki Yong Lee
  • Anthony HaminsEmail author


This paper presents the development of a thin filament pyrometry method to characterize the time-varying temperature field in a medium-scale pool fire burning in a quiescent environment. A digital camera with optical filters and zoom lens was used to record the high temperature emission intensity of 14 µm diameter, silicon-carbide filaments oriented horizontally at various heights above the center of a steadily burning 0.30 m diameter methyl alcohol (methanol; CH3OH) pool fire. Experiments collected 30 Hz video of the planar filament array. In a separate experiment, a 50 µm diameter thermocouple was used to acquire independent temperature measurements in the high temperature zone of the fire. A correlation was developed between the probability density functions of the radiation-corrected thermocouple measurements and the camera grayscale pixel intensity of the filaments. This arrangement enables measurement of the time-varying temperature field over a temperature range from about 1150 K to 1900 K with a spatial resolution of 160 µm, a temporal resolution of 0.033 s, and an expanded uncertainty of about 150 K (at a mean temperature of 1300 K). Measurements of the grayscale pixel intensities of the filaments were obtained. False color maps of the temperature field were produced to characterize the high temperature field as a function of time. Using statistical analysis, the local time-averaged temperatures and their variance for each location on the filaments were determined. Time-averaged temperatures were compared favorably to previously reported measurements. The dominant frequency of the puffing fire was determined. The temperature field time series was transformed to consider its character during consecutive phases of the fire’s puffing cycle. The analysis emphasizes the cyclic nature of a pool fire, providing insight on its complex dynamic structure.


Methanol Pool fires, pyrometry Temperature field measurements 



Many thanks are due to Michael Gollner and Peter Sunderland of the University of Maryland at College Park and Howard Baum of NIST for helpful discussions. The authors are grateful to Nippon Carbon Co and Hugh Spilker of COI Ceramics for providing the SiC filament samples.


  1. 1.
    Cetegen BM, Ahmed T (1993) Experiments on the periodic instability of buoyant plumes and pool fires. Combust Flame 93:157–184CrossRefGoogle Scholar
  2. 2.
    Peacock RD, Reneke PA, Forney GP (2013) CFAST—consolidated model of fire growth and smoke transport (Version 6), NIST Special Publication 1041r1.
  3. 3.
    McGrattan K, McDermott R, Hostikka S, Floyd J, Weinschenk C, Overholt K (2016) Fire dynamics simulator. National Institute of Standards and Technology, Gaithersburg, NIST Special Publication 1019, 6th edn.
  4. 4.
    Hamins A, Johnsson E, Donnelly M (2008) Energy balance in a large compartment fire. Fire Saf J 43:180–188CrossRefGoogle Scholar
  5. 5.
    Hariharan SB, Sluder ET, Gollner MJ, Oran ES (2019) Thermal structure of the blue whirl. Proc Combust Inst 37:4285–4293. CrossRefGoogle Scholar
  6. 6.
    Hariharan SB (2017) The structure of the blue whirl: a soot-free reacting vortex phenomenon, Master’s Thesis, University of Maryland at College ParkGoogle Scholar
  7. 7.
    Pitts WM (1996) Thin filament pyrometry in flickering diffusion flames. In: Proceedings of the twenty-sixth symposium (international) on combustion. The Combustion Institute, pp 1171–1179.
  8. 8.
    Weckman EJ, Strong AB (1996) Experimental investigation of the turbulence structure of medium-scale methanol pool fires. Combust Flame 105:245–266CrossRefGoogle Scholar
  9. 9.
    Hamins A, Lock A (2016) The structure of a moderate-scale methanol pool fire, NIST Technical Note 1928.
  10. 10.
    Kim SC, Lee KY, Hamins A (2019) Energy balance in medium-scale methanol, ethanol and acetone pool fires. Fire Saf J 107:44–53. CrossRefGoogle Scholar
  11. 11.
    Hamins A, Klassen M, Gore J, Fischer S, Kashiwagi T (1993) Heat feedback to the fuel surface in pool fires. Combust Sci Technol 97:37–62CrossRefGoogle Scholar
  12. 12.
    Klassen M, Gore JP (1994) Structure and radiation properties of pool fires, NIST Report GCR-94-651, National Institute of Standards and Technology, GaithersburgGoogle Scholar
  13. 13.
    Buch R, Hamins A, Konishi K, Mattingly D, Kashiwagi T (1997) Radiative emission fraction of pool fires burning silicone fluids. Combust Flame 108:118–126CrossRefGoogle Scholar
  14. 14.
    Corlett RC, Fu TM (1966) Some recent experiments with pool fires. Pyrodynamics 1:253–269Google Scholar
  15. 15.
    OMEGA, Thermocouple response time. Website consulted Accessed 7/1/2018
  16. 16.
    Reotemp Instruments, Type S thermocouples. Website consulted Accessed 7/1/2018
  17. 17.
    Bergman TL, Lavine AS, Incropera FP, DeWitt DP (2011) Fundamentals of heat and mass transfer, 7th edn. Wiley, New YorkGoogle Scholar
  18. 18.
    Ichikawa H (2006) Advances in SiC fibers for high temperature applications. Adv Sci Technol 50:17–23. CrossRefGoogle Scholar
  19. 19.
    Maun JD, Sunderland PB, Urban DL (2007) Thin-filament pyrometry with a digital still camera. Appl Opt 46:483–488CrossRefGoogle Scholar
  20. 20.
    Bedat B, Giovanni A, Pauzin S (1994) Thin filament infrared pyrometry: instantaneous temperature profile measurements in a weakly turbulent hydrocarbon premixed flame. Exp Fluids 17:397–404. CrossRefGoogle Scholar
  21. 21.
    Mathworks Documentation: rgb2gray. Website consulted Accessed 7/1/2018
  22. 22.
    Weckman EJ, Sobesiak A (1988) Proceedings of the twenty-second symposium (international) on combustion. The Combustion Institute, p 1299Google Scholar
  23. 23.
    Hamins A, Yang JC, Kashiwagi T (1992) An experimental investigation of the pulsation frequency of flames. In: Proceedings of the twenty-fourth symposium (international) on combustion. The Combustion Institute, pp 1695–1702Google Scholar
  24. 24.
    Petty MD (2013) Advanced topics in calculating and using confidence intervals for model validation. Spring Simul Interoper Workshop 2013:194–204Google Scholar

Copyright information

© This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply  2019

Authors and Affiliations

  1. 1.National Institute of Standards and TechnologyGaithersburgUSA
  2. 2.State Grid Electric Power Research InstituteNanjingChina
  3. 3.Andong National UniversityAndongRepublic of Korea

Personalised recommendations