The ring fire usually originates from the combustion of the annular‐distributed fuel, and it may occur in the low‐temperature environments such as the Arctic area and plateau area, which is kind of different from the conventional environment. In this paper, the annular pools with various shape characteristics were designed. The outside diameter ranged from 14.9 to 30.0 cm, the inside diameter increased from 0 to 24.5 cm, and the diameter ratio was from 0 to 0.858. A series of n‐heptane ring fire experiments were carried out. The results showed that for the annular pools with the same outside diameter, the mass loss rate (MLR) per unit area presents a piecewise trend with the diameter ratio. When the diameter ratio increases from 0 to 0.7, the MLR per unit area increases linearly because of the domination of air entrainment effect. When the diameter ratio is larger than 0.7, the MLR per unit area is independent of the annular shape due to the strong heat dissipation effect. Finally, a parameter named the outside circumference per unit area is put forward to characterize the annular pool. A corrected pressure modeling is established to normalize the ring fire with various shape characteristics.

中文翻译：

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环形池形状特征对正庚烷环火影响的实验研究

环形火灾通常源自环形分布燃料的燃烧，它可能发生在北极地区和高原地区等低温环境中，这与常规环境有所不同。在本文中，设计了具有各种形状特征的环形池。外径范围为14.9至30.0 cm，内径范围为0至24.5 cm，直径比为0至0.858。进行了一系列正庚烷环烧实验。结果表明，对于具有相同外径的环形池，每单位面积的质量损失率（MLR）随直径比呈分段趋势。当直径比从0增加到0.7时，由于空气夹带效应的主导，每单位面积的MLR线性增加。当直径比大于0.7时，由于强的散热效果，每单位面积的MLR不依赖于环形。最后，提出了一个名为每单位面积外周长的参数来表征环形池。建立校正后的压力模型以规范具有各种形状特征的环形火。