Abstract Although the effect of pressure on the characteristics of laminar diffusion flame has been extensively studied, there is need of simple similarity correlations for flame shape and radiation fraction, which can be useful for application to turbulent flows and fire safety. In this paper, similarity analysis for flow and soot models is developed, where non-dimensional parameters were defined for the flame geometry and the radiation fraction. For validation, small ethanol pool fires with diameter of 1.5 cm were conducted in a pressure chamber at different pressures ranging from 1 to 5 atm, where the flame shape and radiation fraction were measured. Results show the characteristic lengths of the flame geometry including flame height, flame width, flame oscillation length, flame frequency and flame volume could be well correlated using the non-dimensional similarity parameter. Furthermore, the globle relationship for non-dimensional radiation fraction was verifed based on measured value in current and previous study, where the non-dimension radiation fraction could be well correlated by the −0.30 power of S m f μ ν 2 g 1 3 . Comparison with literature experiments are also presented and discusssed.

中文翻译：

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压力对层流射流扩散火焰特性的影响：相似性分析与实验研究

摘要 虽然压力对层流扩散火焰特性的影响已得到广泛研究，但仍需要火焰形状和辐射分数的简单相似关系，这对于湍流和消防安全的应用是有用的。在本文中，开发了流动和烟尘模型的相似性分析，其中定义了火焰几何形状和辐射分数的无量纲参数。为了验证，直径为 1.5 厘米的小型乙醇池火灾在压力室中进行，压力范围为 1 到 5 个大气压，测量火焰形状和辐射分数。结果显示了火焰几何的特征长度，包括火焰高度、火焰宽度、火焰振荡长度、使用无量纲相似性参数可以很好地关联火焰频率和火焰体积。此外，基于当前和先前研究中的测量值验证了无量纲辐射分数的全局关系，其中无量纲辐射分数可以通过S mf μ ν 2 g 1 3 的-0.30次幂很好地相关。还介绍并讨论了与文献实验的比较。