在流合成气燃烧中,在偏好的扩散效应下选择反应进展变量,基于详细的化学直接数值模拟
Vinzenz Silvester Wehrmann1, Nilanjan Chakraborty2, Markus Klein3
1Department of Aerospace Engineering, University of the Bundeswehr Munich, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany. vinzenz.wehrmann@unibw.de.
Scientific reports
|June 27, 2024
概括
一个新的反应进展变量准确地模拟了合成气的燃烧,捕捉了燃烧速度的增加和温度的演变. 这对于非化石能源发电和工艺工程的安全至关重要.
科学领域:
- 燃烧科学是一种科学.
- 化学工程是化学工程的组成部分.
- 核安全问题 核安全问题
背景情况:
- 合成气的燃烧对于非化石能源安全至关重要,特别是在氨合成和核电厂.
- 精确的合成气燃烧子网建模需要了解反应进展变量.
- 偏好的扩散效应显著影响燃烧动态.
研究的目的:
- 为了评估不同反应进度变量用于合成气/空气燃烧.
- 了解燃料成分,流和火焰拓学的影响.
- 为工业规模的燃烧模拟确定可靠的变量.
主要方法:
- 精细的化学直接数值模拟 (DDNS) 瘦/空气和合成气/空气火焰.
- 基于氧,和产物种的反应进展变量的分析.
- 与1D未拉伸的预混合火焰进行比较.
主要成果:
- 基于氧气的进度变量无法捕捉由于偏好的扩散而导致的燃烧速度增加.
- 基于的进度变量捕获燃烧速度的增加,但对火焰曲线敏感.
- 基于产品的进度变量准确地表示温度和燃烧速度的增加,但可以超过1.0.
结论:
- 主要产品的线性组合为合成气燃烧建模提供了一个有前途的反应进展变量.
- 对于超亚的地区,基于产品的变量超过1.0仍然存在挑战.
- 基于的变量提供了边界性,但显示了与火焰曲率的偏差.
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