Changes in Fire Characteristics according to the Distance Between the Fire Source and Sidewall in a Reduced-Scale Compartment

Hong-Seok, Yun; Cheol-Hong, Hwang

doi:2019.33.1.50

Fire Sci. Eng. > Volume 33(1); 2019 > Article

Fire Science and Engineering 2019;33(1):50-59.
DOI: https://doi.org/10.7731/KIFSE.2019.33.1.050 Published online February 28, 2019.

축소 구획실에서 화원과 측벽의 거리에 따른 화재특성 변화

윤홍석, 황철홍

¹대전대학교 대학원 방재학과 대학원
²대전대학교 소방방재학과

Changes in Fire Characteristics according to the Distance Between the Fire Source and Sidewall in a Reduced-Scale Compartment

Yun Hong-Seok, Hwang Cheol-Hong

¹Dept. of Disaster Prevention, Daejeon University
²Department of Fire and Disaster Prevention, Daejeon University

요약

과환기 화재조건에서 화원과 측벽의 거리에 따른 화재특성에 관한 실험 및 수치해석 연구가 수행되었다. 1/3 축소된 ISO 9705 화재실이 제작되었으며, Spruce wood crib이 연료로 사용되었다. 구획 내부의 현상 이해를 위하여 Fire Dynamics Simulator (FDS)를 활용한 시뮬레이션이 수행되었다. 개방된 공간 화재에 비해 구획실 화재는 벽면의 열 피드백 효과로 인하여 질량 감소율과 열발생률이 증가됨이 확인되었다. 측벽과 화원의 거리가 감소됨에 따라 화염으로의 공기 유입 제한에도 불구하고 주요 화재특성인 최대 질량 감소율, 열발생률, 화재 성장률, 온도 및 열유속이 증가되었다. 특히 측벽과 화원이 접촉되었을 때 이들 물리량의 가장 큰 변화가 확인되었다. 추가로 화원과 측벽의 거리에 따른 구획 내부의 유동구조의 변화로 인하여 온도의 수직분포에 상당한 변화가 발생됨이 확인되었다.

Abstract

Experimental and numerical studies on the fire characteristics according to the distance between the fire source and sidewall under the over-ventilated fire conditions. A 1/3 reduced ISO 9705 room was constructed and spruce wood cribs were used as fuel. Fire Dynamics Simulator (FDS) was used for fire simulations to understand the phenomenon inside the compartment. As a result, the mass loss rate and heat release rate were increased due to the thermal feedback effect of the wall in the compartment fire compared to the open fire. As the distance between the fire source and sidewall was reduced, the major fire characteristics, such as maximum mass loss rate, heat release rate, fire growth rate, temperature, and heat flux, were increased despite the limitations of air entrainment into the flame. In particular, a significant change in these physical quantities was observed for the case of a fire source against the sidewall. In addition, the vertical distribution of temperature was changed considerably due to a change in the flow structure inside the compartment according to the distance between the fire source and sidewall.

Key Words: Compartment fire, Fire-wall interaction, Sidewall effect, Thermal feedback, Fire characteristics