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A Numerical Study on Temperature Prediction Bias using FDS in Simulated Thermal Environments of Fire

모사된 화재의 열적환경에서 FDS를 이용한 온도 예측오차에 관한 수치해석 연구

  • Han, Ho-Sik (Department of Fire and Disaster Prevention, Daejeon University) ;
  • Kim, Bong-Jun (Department of Fire and Disaster Prevention, Daejeon University) ;
  • Hwang, Cheol-Hong (Department of Fire and Disaster Prevention, Daejeon University)
  • 한호식 (대전대학교 소방방재학과) ;
  • 김봉준 (대전대학교 소방방재학과) ;
  • 황철홍 (대전대학교 소방방재학과)
  • Received : 2017.01.05
  • Accepted : 2017.04.05
  • Published : 2017.04.30

Abstract

A numerical study was conducted to identify the predictive performance for the bare-bead thermocouple (TC) using FDS (Fire Dynamics Simulator) in simulated thermal environments of fire. A relative prediction bias of TC temperature calculated from reverse-radiation correction by FDS was evaluated with the comparison of previous experimental data. As a result, it was identified that the TC temperatures predicted by FDS were lower than the temperatures measured by bare-bead TC for the ranges of heat flux and gas temperature considered. The relative prediction bias of TC temperature by FDS was gradually increased with the increase in radiative heat flux and also significantly increased with the decrease in the gas temperature. Quantitatively, at the gas temperature of $20^{\circ}C$, the TC temperature predicted by FDS had the relative bias of approximately -20% with the radiative heat flux of $20kW/m^2$ corresponding to thermal radiation level of the flashover. It is predicted from the present study that more accurate validation of fire modeling will be possible with the quantitative prediction bias occurred in the process of reverse-radiation correction of temperature predicted by FDS.

Keywords

temperature;bare-bead thermocouple;radiation correction;fire modeling;FDS(Fire Dynamics Simulator)

Acknowledgement

Supported by : 국민안전처

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