The Lateral Ignition and Flame Spread Test (LIFT) is used to characterize fire ignition and flame spread on solid materials. This test requires the operator to visually monitor the flame spread over a combustible material and manually record the position of the flame during an experiment. Visual inspection limits the quantity of data obtained from a test and introduces uncertainty in the measurement. In this study, we use narrow-spectrum light with a peak wavelength of 450 nm and a digital camera with frequency-matched optical filters to capture images of surface charring, which underlies the flaming combustion, in a LIFT apparatus. The imaging technique reduced unwanted energy emissions from the flame in the visible light spectrum, allowing the test operator to directly view the charring of the material; which is otherwise hidden behind the flames. We describe data processing routines to analyze the sequences of high-resolution images. The method improves temporal and spatial resolution of the surface charring compared to visual observations.

中文翻译：

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窄谱照明和图像处理在横向点火和火焰蔓延测试中测量表面炭形成的应用

横向点火和火焰蔓延测试 (LIFT) 用于表征固体材料上的着火和火焰蔓延。该测试要求操作员目视监控火焰在可燃材料上的蔓延，并在实验过程中手动记录火焰的位置。目视检查限制了从测试中获得的数据量，并在测量中引入了不确定性。在这项研究中，我们使用峰值波长为 450 nm 的窄光谱光和带有频率匹配滤光片的数码相机在 LIFT 设备中捕获表面炭化的图像，这是火焰燃烧的基础。成像技术减少了可见光谱中火焰的有害能量排放，使测试操作员可以直接查看材料的炭化情况；否则隐藏在火焰后面。我们描述了数据处理程序来分析高分辨率图像的序列。与目视观察相比，该方法提高了表面炭化的时间和空间分辨率。