SGER: Auto-ignition of Wood

项目概述：木材自动点火。这是一笔用于探索性研究的小额资助。建立了木材自燃模型，并进行了数值求解。该模型考虑了固相和气相的物理和化学过程。在固气界面边界条件中包含了在固体表面入射热流较低时很重要的炭表面氧化。数值代码可以再现自燃实验结果，并最终解释控制木材自燃的潜在物理和化学过程。自燃是火灾蔓延和发展的重要机制。它具有根本意义，但它的复杂性阻碍了对控制它的重要机制的明确研究。虽然本研究的重点是木材，但所提出的建模也可以涉及其他炭化和非炭化固体。木材在氧气环境中的加热导致原始材料的表面放热氧化和热分解。阴燃点火可以发生在表面，火焰点火也是可能的。这两种点火形式以前在自燃过程中没有加以区分。更广泛的影响这项基础性工作对公众和基础设施的整体安全至关重要。值得注意的是，它包含了森林火灾蔓延的问题，因为这种蔓延涉及到离散木质材料的辐射加热，导致氧化和燃烧。从教育的角度来看，这项工作的结果在一个独特的程序中传递给消防工程专业的学生。这一结果将是第一个解决表面和气相点火过程的同类结果，对公共安全和森林和建筑物中火灾的蔓延具有重要意义。

Project Summary: Auto-ignition of woodThis is a Small Grant for Exploratory Research. A model for autoignition of wood is developed and solved numerically. The model considers physical and chemical processes in both solid and gas phases. The char surface oxidation, important when the incident heat flux to the solid surface is low, is included in the solid-gas interface boundary conditions. The numerical code can reproduce the experimental results for autoignition and ultimately can explain the underlying physical and chemical processes governing the autoignition of wood. Auto-ignition is a significant mechanism in the spread and growth of fire. It is of fundamental interest, but its complexity has prevented a definitive study of the important mechanisms that control it. Although the focus of this study is wood, the proposed modeling can relate to other charring and non-charring solids as well. The heating of wood in an oxygen atmosphere leads to exothermic surface oxidation and thermal decomposition of the virgin material. Smoldering ignition can occur at the surface, and flaming ignition is also possible. These two forms of ignition have not previously been distinguished in the process of autoignition. Broader ImpactThis fundamental work is important to the overall safety of the public and infrastruture. Significantly, it embraces the problem of spread in forest fires since this spread involves the radiant heating of discrete woody material causing oxidation and flaming. From an educational point of view, the results of this work are transmitted to fire-protection engineering students in a unique program. This result will be the first of its kind in addressing both the surface and gas-phase ignition processes, and is significant to public safety and the spread of fire in forests and structures.