Abstract Fire accidents induced by indoor energy combustion occurred frequently and caused tremendous loss. This paper investigated the evolution laws of important fire risk parameters for quantitatively assessing the thermal hazard of room with triangular windows by reduced-scale experiments. The fire hazard was characterized by the risk parameters of hot gas temperature inside the room and facade flame height. Results show that the neutral plane position is hardly affected by total heat release rate of fire source, and it mainly depends on triangular opening height rather than base width. The ratios of neutral plane height above opening bottom to opening height are about 0.25, 0.25 and 0.61 for isosceles, right and inverted right triangular openings respectively. Based on theoretical derivation, an appropriate ventilation factor for triangular opening was defined to describe air mass inflow rate during under-ventilated condition. The hot gas temperature inside the room can be predicted based on the newly defined ventilation factor. Finally, a non-dimensional correlation was proposed to characterize facade flame height as a 0.53 power function of a normalized excess heat release rate. This work is of benefits to evaluate the fire hazard of buildings and then to provide calculation basis for building fire protection design.

中文翻译：

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室内能源使用不可控燃烧致热危害及立面火焰表征实验研究

摘要 室内能源燃烧引发的火灾事故频发，造成巨大损失。本文通过缩尺实验研究了定量评估三角窗房间热危害的重要火灾风险参数的演变规律。火灾危险的特征在于室内热气温度和立面火焰高度的风险参数。结果表明，中性面位置几乎不受火源总热释放率的影响，主要取决于三角形开口高度而不是底部宽度。对于等腰、直角和倒直角三角形开口，开口底部上方的中性面高度与开口高度的比率分别约为0.25、0.25和0.61。基于理论推导，三角形开口的适当通风系数被定义为描述通风不足条件下的空气质量流入率。可以根据新定义的通风系数预测房间内的热气温度。最后，提出了一种无量纲相关性，将立面火焰高度表征为归一化过量热释放率的 0.53 幂函数。该工作有利于评价建筑物的火灾危险性，为建筑物的防火设计提供计算依据。53 归一化过量放热率的幂函数。该工作有利于评价建筑物的火灾危险性，为建筑物的防火设计提供计算依据。53 归一化过量放热率的幂函数。该工作有利于评价建筑物的火灾危险性，为建筑物的防火设计提供计算依据。