Abstract The behaviors of fires fueled by materials that produce different levels of soot (diesel and alcohol) were studied under hot and humid conditions with natural ventilation. Experimental tests were performed under different initial ambient temperatures (20 °C and 30 °C) and relative humidity levels (50% and 90%), and flame temperature, thermal radiation and mass loss rate were measured. A theoretical flame radiation model was established and verified. The fire development index (FDI) was defined as the ratio of the peak flame temperature, Tp, to the duration, tp, during initial fire development stage, and the fire severity index (FSI) was defined as the product of the flame thermal radiation, Rav, and the duration, td, during fully developed stage. The results validated the reasonableness of the established theoretical model. During initial fire development stage, increasing the initial ambient temperature increased the FDI, while increasing the relative humidity decreased it. During fully developed stage, increasing the initial ambient temperature or humidity resulted in a decrease in the FSI under limited-fuel conditions, and the ambient temperature more significantly affected the pool fires fueled by alcohol than those that consumed diesel. Additionally, under conditions of high temperature and high humidity, both the indices were reduced.

中文翻译：

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不同烟度等级燃料在湿热条件下的着火行为

摘要 研究了在自然通风的湿热条件下由产生不同水平烟尘（柴油和酒精）的材料助长的火灾行为。在不同的初始环境温度（20°C 和 30°C）和相对湿度水平（50% 和 90%）下进行了实验测试，并测量了火焰温度、热辐射和质量损失率。建立并验证了理论火焰辐射模型。火灾发展指数 (FDI) 定义为火灾发展初期峰值火焰温度 Tp 与持续时间 tp 的比值，火灾严重性指数 (FSI) 定义为火焰热辐射的乘积、Rav 和完全发育阶段的持续时间 td。结果验证了所建立的理论模型的合理性。在火灾发展初期，提高初始环境温度会增加 FDI，而增加相对湿度会降低 FDI。在完全发育阶段，增加初始环境温度或湿度导致有限燃料条件下 FSI 降低，并且环境温度对酒精燃料池火灾的影响比柴油燃料池火灾影响更大。此外，在高温高湿条件下，这两个指标均有所下降。与使用柴油的池火相比，环境温度对以酒精为燃料的池火的影响更大。此外，在高温高湿条件下，这两个指标均有所下降。与使用柴油的池火相比，环境温度对以酒精为燃料的池火的影响更大。此外，在高温高湿条件下，这两个指标均有所下降。