附加挡板集中排烟模式优化研究  

Study on optimization of centralized smoke exhaust mode with additional baffle

作　　者：姜学鹏[1,2,3] 张键鸿 吕彦昕 JIANG Xuepeng;ZHANG Janhong;LU Yanxin(School of Resource and Environmental Engineering,Wuhan University of Science and Technology,Wuhan 430081,China;Fire Safety Technology Institute,Wuhan University of Science and Technology,Wuhan 430081,China;Industrial Safety Engineering Technology Research Center of Hubei Province,Wuhan University of Science and Technology,Wuhan 430081,China)

机构地区：[1]武汉科技大学资源与环境工程学院,武汉430081 [2]武汉科技大学消防安全技术研究所,武汉430081 [3]武汉科技大学湖北省工业安全工程技术研究中心,武汉430081

出　　处：《安全与环境学报》2023年第9期3172-3179,共8页Journal of Safety and Environment

基　　金：国家自然科学基金项目(51874213);湖北省重点研发计划项目(2020BCB072)。

摘　　要：为改善公路隧道集中排烟时产生的吸穿现象,优化传统顶部集中排烟模式,采用火灾动力学模拟工具(Fire Dynamics Simulator,FDS)建立全尺寸模型对附加排烟挡板的不同火源功率及排烟口尺寸隧道集中排烟模式进行探讨,对排烟口区域流场、温度场以及CO体积流量进行分析。结果显示:附加水平挡板能有效改善吸穿现象,挡板与排烟口尺寸比k达到1.5后能够起到较好的排烟效果;此时继续增加挡板尺寸对系统排烟能力提升有限,挡板在距排烟口0.3 m时,系统排烟能力最佳;此时发生完全吸穿现象的临界弗罗德数Fr=2.3,大于前人给出完全吸穿Fr=1.8的判据。FDS is used to establish a full-scale model to discuss the improvement of Suction through phenomenon.First,the research is carried out under the 10/15 MW fire scenario by changing the ratio of the baffle to three different sizes of smoke vents(k=Lp/Lvent)and the installation height of different baffles.The results show that the additional horizontal baffle can effectively improve the suction-through phenomenon by analyzing the flow field,temperature field,and CO volume flow in the area of the exhaust port.The temperature,the volume flow of CO,and the exhaust efficiency below the exhaust port tend to be stable after k=1.5,so the optimal size ratio k of the baffle is determined to be 1.5.When the installation height of the baffle is 0.3 m away from the exhaust port,the CO content in the exhaust flue gas is the largest,and the exhausting ability is the strongest.Therefore,it is determined that the optimal size ratio k of the horizontal baffle is 1.5,and the optimal installation height h is 0.3 m.Finally,in the case of adding the optimal size and installation height of the horizontal plate,the critical smoke emission volume of 5/10/15 MW three kinds of firepower is studied by changing the exhaust air speed.The critical Frode number under different smoke exhaust volumes is calculated by analyzing the key parameters such as the temperature and thickness of the flue gas layer.And the results show that the additional baffle can prevent the smoke from sinking to the evacuation height under the same fire source power and smoke exhaust volume.This is because the cold air enters from both sides of the baffle,rather than vertically into the exhaust port,when suction through the centralized smoke exhaust mode of the additional baffle occurs.The calculated Frode number F,=2.3 when the phenomenon of complete suction-through occurs,which is greater than the criterion of F,=1.8 given by the predecessors.

关 键 词：安全工程 集中排烟 排烟挡板 吸穿 临界弗罗德数 

分 类 号：X959[环境科学与工程—安全科学]