倾斜隧道贴壁火灾顶棚烟气最大温升模拟研究  

Study on Maximum Ceiling Smoke Temperature Rise of Inclined Tunnel Wall Fires

作　　者：张培红[1] 何晓祥 郭尹亮[1] ZHANG Peihong;HE Xiaoxiang;GUO Yinliang(School of Resources and Civil Engineering,Northeastern University,Shenyang,China,110819)

机构地区：[1]东北大学资源与土木工程学院,辽宁沈阳110819

出　　处：《沈阳建筑大学学报（自然科学版）》2024年第2期232-240,共9页Journal of Shenyang Jianzhu University：Natural Science

基　　金：国家自然科学基金项目(52374188,51774067)。

摘　　要：目的 研究在火灾浮力效应、壁面辐射热反馈及空气卷吸限制效应的协同作用下倾斜隧道贴壁火灾发展的特性。方法 利用FDS软件对倾斜隧道贴壁火进行数值模拟,分析顶棚烟气最大温升及其位置;考虑火源中心与侧壁的距离、坡度,建立了无量纲预测模型,进行拟合分析。结果 当贴壁火热释放速率分别为2.7、4.0和5.0 MW时,隧道贴壁火的顶棚最大温升分别在坡度为2%、1%、0时达到最大值,之后随着坡度的增大呈指数衰减;与轴线火相比,当坡度小于10%时,贴壁火的最大温升点与火源中心更近,坡度大于10%时,贴壁火的最大温升点位置更远;贴壁火和轴线火的拟合结果很好,相关系数分别为0.98和0.95。结论 侧壁限制对最大温升的影响随着火源中心与侧壁距离的缩小而更加显著;随着隧道坡度增大,倾斜隧道贴壁火的火焰同时向火灾上游和侧壁倾斜,空气卷吸和对流换热作用不断增强,从而影响火焰的受力机制和火源表面接受到的辐射热反馈,顶棚最大温升随坡度增加呈指数衰减。To study the particularity of fire development law in inclined tunnel wall fire under the synergistic effect of fire buoyancy effect,wall radiant heat feedback and air entrainment restriction mechanism,using FDS to analyze the maximum ceiling smoke temperature rise and its location in inclined tunnel wall fire,considering slope and distance between the fire center and the side wall,a dimensionless prediction model of ceiling smoke maximum temperature rise and maximum temperature rise point is constructed.In inclined tunnel wall fire,the influence of the side wall limitation on the maximum temperature rise is more significant with the decrease of the distance between the fire source center and the side wall.The maximum temperature rise of the heat release rate of 2.7,4 and 5 MW tunnel wall fire reaches a maximum at 2%,1%and 0 slope respectively;As the slope continues to increase,the maximum ceiling smoke temperature rise decays exponentially with tunnel slope.Compared with the axis fire,it is closer that the distance between the maximum temperature rise point of the wall fire and the center of the fire source when the slope is less than 10%,when the slope is greater than 10%,the position of the maximum temperature rise point of the wall fire is slightly farther.With the increase of tunnel slope,air enrolling and convective heat transfer are continuously enhanced,and the flame of inclined tunnel wall fire tilts towards the upstream and side wall at the same time,which affects the force mechanism of the flame and the radiant heat feedback received by the fire source surface,the maximum temperature rise of the ceiling decreases exponentially with the increase of the slope.

关 键 词：倾斜隧道 贴壁火 轴线火 最大温升 最大温升点位置 

分 类 号：X932[环境科学与工程—安全科学]