Journal of the Korean Society of Safety (한국안전학회지)

The Korean Society of Safety (한국안전학회)
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An Experimental Study on Temperature Measurement Bias using Thermocouple in Simulated Thermal Environments of Fire

모사된 화재의 열적환경에서 열전대를 이용한 온도 측정오차에 관한 실험적 연구

  • Han, Ho-Sik (Department of Fire and Disaster Prevention, Daejeon University) ;
  • Yun, Hong-Seok (Department of Fire and Disaster Prevention, Daejeon University) ;
  • Hwang, Cheol-Hong (Department of Fire and Disaster Prevention, Daejeon University) ;
  • Kim, Sung-Chan (Department of Fire Safety, Kyungil University)
  • Received : 2016.12.17
  • Accepted : 2017.02.14
  • Published : 2017.04.30
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Abstract

An experimental study was conducted to identify the quantitative measurement bias for the bare-bead thermocouple (TC), which was widely used for measuring temperature in fire experiments. To this end, an apparatus could be controlled individually gas flow rate, preheating temperature and incident radiative heat flux was developed to simulate the thermal environments of fire. A relative measurement bias of bare-bead TC was evaluated with the comparison of double-shield aspirated TC. As a result, the relative measurement bias of bare-bead TC was gradually increased with the increase in radiative heat flux with constant gas temperature. The relative bias was also significantly increased with the decrease in gas temperature. Quantitatively, at the gas temperature of $20^{\circ}C$, the bare-bead TC had the relative bias of approximately 400% with the radiative heat flux of $20kW/m^2$ corresponding to thermal radiation level of the flashover. The present study was intend to provide fire researchers with methodologies for the reanalyses of temperature measured using bare-bead TC, radiation corrections, and validation of fire modeling.

Keywords

References

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