Freely propagating, one-dimensional, laminar, premixed flames of ethylene–air are analysed at standard temperature and pressure (STP) and at elevated temperature and pressure conditions to reveal the differences in flame structure. For high-temperature and low-pressure conditions, there is a significant contribution to the total heat release in the post-flame region leading to an ambiguity in the definition of the characteristic flame structure thickness. The potential implications on the identification of the appropriate turbulent flame regime in Borghi or Re-Da regime diagrams are highlighted. The contributions of individual reactions to the total heat release across the entire flame structure are analysed to understand the impact of turbulence–chemistry interactions.

中文翻译：

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高度预热混合物的预混火焰厚度定义的模糊性及其对湍流燃烧状态的影响

在标准温度和压力 (STP) 以及升高的温度和压力条件下对乙烯-空气的自由传播、一维、层流、预混火焰进行分析，以揭示火焰结构的差异。对于高温和低压条件，对火焰后区域的总热量释放有显着贡献，导致特征火焰结构厚度的定义不明确。强调了在 Borghi 或 Re-Da 状态图中识别合适的湍流火焰状态的潜在影响。分析单个反应对整个火焰结构总热量释放的贡献，以了解湍流-化学相互作用的影响。