Collaborative Research: A Fundamental Investigation of Fire Initiation and Fire Behavior in Sparse Vegetation

本合作研究项目的目的是开发先进的建模技术，用于描述低冠层容重植被的火灾发生和传播。预测野火蔓延的能力对于保护生命、财产和自然资源至关重要。目前的操作模型可以很好地预测模型相关条件下的整体火灾行为（例如，死燃料床），但对于活灌木或高水分含量的树木，它们的表现并不好。详细的物理模型，无论是在实验室还是在景观尺度上，都需要改进的亚网格尺度的燃烧模型，特别是在描述由于植被相对稀疏而不像密集燃料床的植被中的火灾行为时。这项技术将基于对活燃料的基本燃烧测量，但它将适用于景观尺度火灾的模型。研究目标将通过四个相互关联的任务来实现：(1)活叶和小枝中的火焰传播测量；(2)灌木中不同体积密度的火焰传播测量；(3)灌木和树木的火焰传播模型；(4)多灌木火灾行为模型。这项研究将为火灾蔓延现象提供一个连贯的画面，从单个燃料元件（如一片叶子）的点火开始，到通过更大的燃料阵列（如森林）自我维持的火灾蔓延。所研究的基本物理和化学过程也与导致树冠火灾的表面火焰传播问题有关。提高对稀疏植被中火灾行为的基本理解将有助于提高其他领域的预测能力，如火灾安全或纵火调查，以确定火源。了解在稀疏的植物燃料床中火灾可能或不可能蔓延的条件，将有助于了解如何通过改进燃料管理更有效地控制这些燃料类型中的火灾蔓延。该研究项目聚焦于稀疏植被中的火灾行为，通过提供一种新的创新方法来探索从单一燃料元件到多种燃料元件的点火和燃烧，将激发加州大学洛杉矶分校和杨百翰大学工程专业少数民族和女性研究生学习的兴趣。在加州大学洛杉矶分校和杨百翰大学接受培训的研究生和本科生将有独特的机会与美国农业部林业局在里弗赛德和蒙大拿州实验室的科学家密切互动。这项研究有可能被关注灌木林地火灾蔓延的国际组织使用，这些组织包括澳大利亚、地中海周边国家、南非和智利。

0933785MahalingamThe purpose of this collaborative research project is to develop advanced modeling technology for describing fire initiation and propagation in vegetation with low canopy bulk density. The ability to predict the spread of wildland fires is paramount in protecting life, property, and natural resources. Current operational models predict overall fire behavior well for the conditions for which the model was correlated (e.g., dead fuel beds), but they do not perform as well for live bushes or trees with high moisture content. Detailed physical models, at either laboratory or landscape scale, require improved sub-grid scale models of combustion, especially to describe fire behavior in vegetation that does not act like a dense fuel bed due to the relative sparseness of the vegetation. This technology will be based on fundamental combustion measurements of live fuels, but it will apply to models of landscape-scale fires. The research objective will be achieved via four inter-related tasks: (1) flame propagation measurements in live leaves and small branches, (2) fire spread measurements in shrubs for varying bulk densities, (3) flame propagation models of bushes and trees, and (4) multi-bush fire behavior models.The research will provide a cohesive picture of the phenomenon of fire spread starting from ignition of a single fuel element, such as a leaf, to a self-sustaining fire spreading through a larger fuel array such as a forest. The fundamental physical and chemical processes investigated are also relevant to the problem of surface fire propagation leading to ignition of crown fires. An improved fundamental understanding of fire behavior in sparse vegetation will be beneficial in promoting better predictive capability in other areas such as fire safety or arson investigation pertaining to identifying ignition sources. Gaining an understanding of the conditions under which a fire may or may not propagate within a sparse vegetative fuel bed will provide understanding of how to control fire spread more effectively in these fuel types through improved fuel management. This research program focused on fire behavior in sparse vegetation will stimulate interest in graduate studies among ethnic minorities and women in engineering at both at UCR and BYU by providing a new and innovative means of exploring ignition and combustion from single fuel elements to fire spread through multiple fuel elements. Graduate and undergraduate students trained at UCR and BYU will have the unique opportunity to interact closely with scientists at the USDA Forest Service laboratories in Riverside and Montana. This research has the potential to be used by international organizations concerned with fire spread in shrub lands which includes Australia, countries surrounding the Mediterranean Sea, South Africa, and Chile.