Abstract Since the horizontal projection upon the building facade are widely used in vertical fire-induced thermal protection, this paper is focused on the temperature decay beneath a horizontal projection of spilled plumes from a compartment window. A series of 1:8 reduced scale experiments were carried out in a cubic compartment. The window dimensions as well as the total heat release rates were variable, whilst the temperature was measured by thermocouples installed beneath a horizontal projection, which was located right attached to the facade wall at the top of the compartment window. The temperature field beneath the horizontal projection was found to be singular to a naturally formed ceiling jet. The elongation of temperature field in the longitudinal direction was observed, which should be attributed to the extra horizontal velocity provided by the window spilled plume, and meanwhile, the horizontal velocity started to take advantage as the flow spreads. Finally, the temperature decay in both longitudinal and transversal directions are well correlated by dimensionless functions. The results would provide crucial references in the realistic interpretation on the thermal and strength performance of building structure in building fire scenarios.

中文翻译：

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舱室窗溢出羽流水平投影下温度衰减的实验研究

摘要 由于建筑物立面上的水平投影广泛用于垂直火灾引起的热防护，因此本文重点研究从隔间窗户溢出的羽流水平投影下的温度衰减。在立方隔间中进行了一系列 1:8 缩小比例的实验。窗户尺寸以及总热量释放率是可变的，而温度是通过安装在水平投影下方的热电偶测量的，该水平投影位于隔间窗户顶部的立面墙上。发现水平投影下方的温度场对于自然形成的天花板射流来说是奇异的。观察到温度场在纵向上的伸长率，这应该归因于窗口溢出羽流提供的额外水平速度，同时，随着流动的扩散，水平速度开始发挥作用。最后，纵向和横向的温度衰减与无量纲函数密切相关。研究结果将为真实解释建筑火灾场景中建筑结构的热性能和强度性能提供重要参考。