【作者】 翁韬；

【导师】 廖光煊；

【作者基本信息】 中国科学技术大学 ， 安全技术及工程， 2007， 博士

【摘要】 城镇森林交界域(Wildland-Urban interface，WUI)火灾是新的课题，国外对城镇森林交界域火灾的研究已经成为热点。与发达国家相比，我国在城镇森林火灾防治的研究方面总体上处于落后状态，在相关关键技术的研究方面基本上处于空白，导致在实际建设城镇森林工程时缺乏科学参考和技术手段。面向城镇森林交界域火灾防治的重大需求，围绕城镇森林交界域火灾这一国际火灾科学的前沿课题，研究基于热辐射机制的城镇森林交界域的火蔓延模型，预测火灾发展的趋势，发展城镇森林交界域火灾预测应急辅助决策系统，为有效应对城镇森林交界域火灾提供科学的方法和技术指导，是本文的研究目标。首先，以典型树冠火为对象，研究典型树冠火对建筑的热辐射影响，从而建立城镇森林交界域典型的火行为模型。根据热辐射的可叠加性，通过深入研究实际植被的火焰特征，在单树直圆柱热辐射几何模型的基础上，发展了单树斜圆柱热辐射几何模型，并应用环路积分法求解了上述几何模型的视角系数，并进一步扩展到多树情况下，建立了多树热辐射的简化模型。通过对典型树冠火热辐射的实验研究，以雪松为实验树，测量了实验树的热释放速率、由单颗雪松产生的树冠火的空间热辐射随时间的变化，并将测量值与利用单树热辐射模型计算出的理论值进行了对比分析，验证了单树热辐射模型的合理性；然后测量了由多个雪松同时燃烧产生的空间热辐射随时间的变化，并将测量值与利用多树热辐射模型计算出的理论值进行了对比分析，验证了多树热辐射模型的合理性。研究表明在开放空间无外部通风或通风较弱的条件下，单树热辐射模型和多树热辐射模型能够较为准确的预测树冠火辐射热流密度随时间的变化。接着，利用元胞自动机模型来建立城镇森林交界域火蔓延模型，从理论上研究分析了城镇森林交界域燃料分布的特点。通过研究，给出了城镇森林交界域火蔓延有植被到植被的火蔓延、植被到建筑的火蔓延、建筑到建筑的火蔓延和建筑到植被的火蔓延四种类型；在Berjak的林火元胞自动机火蔓延子模型和A.Ohgai的社区元胞自动机火蔓延子模型基础上，分别建立了建筑到植被火蔓延子模型和植被到建筑火蔓延子模型，综合植被到植被火蔓延子模型、建筑到建筑火蔓延子模型、建筑到植被火蔓延子模型和植被到建筑火蔓延子模型四个子模型，构建了适合整个城镇森林交界域的复合火蔓延模型。最后，将元胞自动机与GIS网格结合起来，以复合火蔓延模型为核心，以SuperMap和VC++为平台设计建立了城镇森林交界域火灾应急辅助决策系统，利用该系统对Black Tiger典型城镇森林交界域实际的火灾案例进行案例分析，通过模拟实际的火灾过程，分析了系统的实用性。研究表明，建立的Black Tiger城镇森林交界域火灾应急辅助决策系统可以形象直观的模拟火蔓延过程，火蔓延趋势与实际的Black Tiger火灾事故发展的趋势一致；在相同时间内火蔓延燃烧过的距离与实际记录的距离大致一致；系统能较好的模拟森林火蔓延的发展趋势；系统能够模拟决策建筑是否烧毁，建筑燃烧蔓延的情况符合实际。更多还原

【Abstract】 Wildland-Urban interface (WUI) fire is a new issue in fire science, and is becoming one of the hotspots of WUI fire. In contrast with the developed countries, the WUI fire research in china poses a relatively under developed state, remaining much blankness in those correlative key techniques and leading to the lacking of scientific references and technical methods in real city construction projects. Facing the great needs of WUI fire prevention and encircling the international frontier subject of fire spread in WUI fire, this paper focuses in the construction of fire spread model based on thermal radiation mechanism of WUI fire to predict the fire spread trend and in developing the Aid-Decision for Emergency response in Wildland-Urban Interface with in-time scientific guiding and technical reference of WUI fire as our objections.Firstly, taking crown fire as the typical object, we studied the thermal radiationeffect of crown fire to the construction and built the WUI fire behave model.According to the superposition ability and through fire characteristics of realvegetation, we developed the thermal geometry radiation model of inclined columnfor single tree and calculated its visual angle coefficient, and expanded it to thesituation of multiple trees forming the simplified model of multi-tree thermal radiation.Through experimental study of typical crown fire using pine tree, we first measuredits heat release rate and the inter-space thermal radiation variation of crown fire ofsingle pine tree and compared the experimental data with the model prediction,validating the rationality of the thermal radiation model of single tree. At last, wemeasured the inter-space thermal radiation variation of multiple trees combustion andalso compared the results with the model prediction. The research showed that underthe condition of no outer ventilation/low ventilation in open space, the single treemodel and multiple trees model can accurately predict the variation of radiation heatflux. Secondly, using cellular automaton model to construct the WUI fire spread model, we theoretically analyzed the fuel distribution of WUI and gave the four fire spread models in WUI fire spread including the fire spread from vegetation to vegetation, fire spread from vegetation to construction, fire spread from construction to construction and the fire spread from construction to vegetation, based on the Berjak’s fire spread model and A.Ohgai’s model, forming the multiplex fire spread model suit for the entire WUI fire.At last, combining the cellular automaton and the GIS network grid, circling themultiplex fire spread model, we set up the Aid-Decision system for Emergencyresponse through computer techniques and performed the case study of Black Tigerfire with the system. According to the real fire spread process, we examined thepracticability of this system. The result showed that the Aid-Decision system forEmergency response can visually and simulate the fire spread process of Black Tigerfire. The simulation of fire spread matches the real fire development well. Result alsoshowed that the fire spread distance of simulation is approximate to the recording data,proving that this system can well simulate the tendency of forest fire spread and thepossibility of damage to the construction.更多还原