摘要
与普通地上建筑房间不同,半地下室的采光通风通常依赖于房间上部的扁平窗户,一旦发生火灾,溢出火焰将对地上整栋建筑产生灾害性影响,并且外界正向风也会进一步影响溢出火焰形态特征,针对这种通风条件下的开口火溢流行为仍缺乏研究.通过利用小尺寸腔室火灾实验平台,开展了风洞实验研究,模拟正向风作用下半地下室窗口火溢流行为,研究了扁平开口位于腔室顶部时,溢出火焰高度随火源热释放速率和正向风风速的演化规律.实验结果表明,溢出火焰充满整个腔室开口且呈现明显的“贴壁火”燃烧状态,火焰高度随热释放速率的增大而增大,随正向风风速增大而减小.通过对影响火焰高度的因素进行无量纲分析,建立了正向风作用下类似于半地下室窗口溢出火焰高度的无量纲理论模型Z_(f)/l_(1)=1.65(1+Fr)^(-0.26)Q_(ex)^(*2/3),外立面无量纲火焰高度与无量纲溢出热释放呈现2/3的指数关系(Z_(f)/l_(1)~Q_(ex)^(*2/3)),与经典的壁面火焰高度模型一致.
Unlike the common compartment,the semi-basement usually depends on the window which is narrow and elevated to top high up on the wall near the ceiling to meet the need of lighting and aeration.Once the semi-basement is on fire,the ejected flame will have disastrous effects on the whole building above the ground,and the external facing wind will affect the facade flame as well,which still lacks researches.This paper utilized a re-duced-scale fire compartment and a wind tunnel to conduct a series of simulating experiments on semi-basement fire.The ejected flame height from the window under various heat release rates and external facing wind speeds was measured.Results show that the ejected flame blocks the opening and extends flatly against the facade.The flame height increases with increasing heat release rate but decreases with increasing wind speeds.The experimental re-sults are interpreted by the dimensionless analysis.A non-dimensional model for the flame height under various conditions is proposed.
作者
侯路遥
孙协鹏
易继威
胡隆华
Hou Luyao;Sun Xiepeng;Yi Jiwei;Hu Longhua(State Key Laboratory of Fire Science,University of Science and Technology of China,Hefei 230026,China)
出处
《燃烧科学与技术》
CAS
CSCD
北大核心
2023年第3期313-318,共6页
Journal of Combustion Science and Technology
基金
国家自然科学基金重点国际合作研究资助项目(52020105008)
国家自然科学基金资助项目(52206181).
关键词
正向风
半地下室窗口
腔室火灾
溢出火焰高度
external facing wind
semi-basement window
compartment fire
facade flame height
