NO producing mechanism and effects of additional water vapor on NO reduction of n-decane/air flames were examined numerically in the present study. A new phenomenon was found that the variation trend of contribution of chemical effect of water vapor on NO reduction with pressure changes with the equivalence ratio. To illustrate this, NO emissions without and with water vapor addition were examined. Results showed that the new phenomenon is because that NO-producing pathways vary with both equivalence ratio and pressure, and hence the reactions through which the added water vapor influences NO production also vary with equivalence ratio and pressure.

中文翻译：

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添加水蒸气对正癸烷/空气火焰NO还原的影响

在本研究中，通过数值研究了NO产生的机理和额外的水蒸气对正癸烷/空气火焰NO还原的影响。发现了一种新的现象，即水蒸气的化学作用对NO还原的贡献随压力当量比的变化趋势。为了说明这一点，研究了不添加水蒸汽和添加水蒸汽的NO排放。结果表明，新现象是因为当量比和压力都改变了NO的产生途径，因此添加水蒸气影响NO产生的反应也随当量比和压力而变化。