Supercritical hydrothermal combustion is a novel, clean, and efficient combustion method. In this work, a mechanism-based kinetic model of ethanol appropriate for high-pressure hydrothermal environment was developed. Combined with theoretical analysis and continuous ignition experiments, the transient ignition process, ignition temperature, and extinction temperature were discussed. A turbulent combustion model coupling detailed kinetics was constructed to analyze the co-flow diffusion hydrothermal flame. It was found that the ethanol kinetic model can well predict the reaction process, critical ignition temperatures, extinction temperatures, and diffusion combustion process of hydrothermal combustion. The ignition temperatures of 2.40–5.72 wt% ethanol ranged between 500–390 °C, and OH was a significant ignition indicator. As an auxiliary fuel, ethanol is superior to methanol. During co-flow hydrothermal combustion, the interfacial reaction between fuel and oxidant in jet core area had an important influence, and the local high-temperature flame was mainly distributed near the downstream of fuel jet.

中文翻译：

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乙醇在超临界水中的动力学及水热燃烧特性

超临界水热燃烧是一种新型、清洁、高效的燃烧方法。在这项工作中，开发了一种适合高压水热环境的基于机理的乙醇动力学模型。结合理论分析和连续点火实验，讨论了瞬态点火过程、点火温度和熄灭温度。构建了耦合详细动力学的湍流燃烧模型来分析并流扩散热液火焰。研究发现乙醇动力学模型可以很好地预测水热燃烧的反应过程、临界着火温度、熄灭温度和扩散燃烧过程。 2.40-5.72 wt% 乙醇的着火温度范围在 500-390 °C 之间，OH 是一个重要的着火指示剂。作为辅助燃料，乙醇优于甲醇。并流水热燃烧过程中，射流核心区燃料与氧化剂的界面反应产生重要影响，局部高温火焰主要分布在燃料射流下游附近。