This paper investigates the temperature evolution inside a compartment (i.e., room) as well as the external flame height ejected through the opening (i.e., window) of fire compartment, which is associated with complex thermal heat/mass transfer and fluid dynamics. The scale effect on this problem is revealed and quantified employing the multi-scale compartments (inner scale ranged from 0.34 to 0.76 m). The fire heat release rate (Global Equivalence Ratio, GRE), opening sizes and compartment scales were varied with 468 experimental conditions. Models for predicting the upper-part temperature evolution with heat release rate (Global Equivalence Ratio, GRE), opening dimensions and compartment scales are established base on the heat balance analysis and the derived non-dimensional quantities. The external flame height shows a considerable difference for various compartment scales, due to the change of temperature inside the compartment hence buoyancy flux of the out-flow through the opening. A general model characterizing the external flame height of various compartment scales is proposed with the newly defined dimensionless excess heat release rate accounting for opening geometry length scale and the upper-part temperature inside the compartment, which shows a good agreement with the experimental results. This study provides important and new contributions over previous knowledge and has potential practical applications generally concerning the scale effect and for the validation of numerical models.

本文研究了车厢（即房间）内部的温度变化以及通过开口（即，防火窗），这与复杂的热/质传递和流体动力学有关。使用多标度隔室（内部标度范围为0.34至0.76 m）显示并量化了对此问题的标度影响。火热释放速率（全球当量比，GRE），开孔尺寸和隔室规模随468个实验条件而变化。基于热量平衡分析和导出的无量纲量，建立了用放热率（全局当量比，GRE），开口尺寸和隔室尺度预测上部温度变化的模型。由于隔室内部温度的变化，因此外部火焰高度对于各种隔室比例显示出相当大的差异，因此流出通过开口的浮力通量。利用新定义的无量纲多余热量释放速率，考虑了开口几何长度标尺和舱室内部上部温度，提出了一个表征各种舱室刻度外部火焰高度的通用模型。这与实验结果吻合良好。这项研究为以前的知识提供了重要而又新的贡献，并具有潜在的实际应用，通常涉及比例效应和数值模型的验证。