Comparison of the Flame Height of Pool Fire according to Combustion Models in the FDS

Ho-Sik, Han; Cheol-Hong, Hwang; Chang Bo, Oh; Dongwon, Choi; Sangkyu, Lee

doi:2018.32.3.42

Fire Sci. Eng. > Volume 32(3); 2018 > Article

Fire Science and Engineering 2018;32(3):42-50.
DOI: https://doi.org/10.7731/KIFSE.2018.32.3.042 Published online June 30, 2018.

FDS의 연소모델에 따른 풀화재의 화염높이 비교

한호식, 황철홍, 오창보, 최동원, 이상규

¹대전대학교 소방방재학과
²대전대학교 소방방재학과
³부경대학교 안전공학과
⁴한국원자력안전기술원 계통평가실
⁵한국원자력안전기술원 계통평가실

Comparison of the Flame Height of Pool Fire according to Combustion Models in the FDS

Han Ho-Sik, Hwang Cheol-Hong, Oh Chang Bo, Choi Dongwon, Lee Sangkyu

¹Department of Fire and Disaster Prevention, Daejeon University
²Department of Fire and Disaster Prevention, Daejeon University
³Department of Safety Engineering, Pukyong National University
⁴Department of Reactor System, Korea Institute of Nuclear Safety
⁵Department of Reactor System, Korea Institute of Nuclear Safety

요약

Large Eddy Simulation (LES) 기반의 Fire Dynamics Simulator (FDS) Version(5와 6)에 따른 아격자 난류 및 연소모델의 변화가 헵탄 풀화재의 평균 화염높이에 미치는 영향이 검토되었다. 화재시뮬레이션을 위한 열발생률은 동일한 조건에서 수행된 실험을 통해 제공되었으며, FDS Version에 따른 평균 화염높이의 예측성능은 기존 상관식과의 비교를 통해 평가되었다. FDS 5와 6에 각각 적용된 Smagorinsky 및 Deardorff 난류 모델은 평균 유동장, 화염형상 및 화염높이에 큰 영향을 주지 않는다. 그러나 평균 화염높이를 포함한 풀화재 특성 차이는 주로 FDS 5와 6에 각각 적용된 혼합분율 및 Eddy Dissipation Concept (EDC) 연소모델 차이로 인하여 발생됨을 확인하였다. 마지막으로 FDS 6에 비해 FDS 5는 상당히 긴 화염높이의 예측결과를 제공하며, 기존 상관식과 보다 일치하는 평균 화염높이 예측이 가능함을 확인하였다.

Abstract

The effect of sub-grid turbulence and combustion models on the mean flame height in a heptane pool fire according to the Fire Dynamics Simulator (FDS) version (5 and 6) based on Large Eddy Simulation (LES) was examined. The heat release rate for the fire simulation was provided through experiments performed under identical conditions and the predictive performance of the mean flame height according to FDS version was evaluated by a comparison with the existing correlation. As a result, the Smagorinsky and Deardorff turbulence models applied to FDS 5 and 6, respectively, had no significant effects on the mean flow field, flame shape and flame height. On the other hand, the difference in pool fire characteristics including the mean flame height was due mainly to the difference in the mixture fraction and Eddy Dissipation Concept (EDC) combustion models applied to FDS 5 and 6, respectively. Finally, compared to FDS 6, FDS 5 provided the predictive result of a significantly longer flame height and more consistent mean flame height than the existing correlation.

Key Words: Fire Dynamics Simulator (FDS), Flame height, Pool fire, Combustion model, Turbulence model