Direct numerical simulations of turbulent jet ignition (TJI)-assisted combustion of lean hydrogen–air mixtures are performed in a three-dimensional planar jet configuration for various thermo-chemical conditions. TJI is a novel ignition enhancement method which facilitates the combustion of lean and ultra-lean fuel–air mixtures by rapidly and continuously exposing them to high temperature combustion products. Fully compressible gas dynamics and species equations are solved with high order finite difference methods. The hydrogen–air reaction is simulated by a detailed chemical kinetics mechanism. Turbulence–combustion interactions in TJI systems are studied here for different conditions using the flame heat release, temperature, species concentrations, and a newly defined progress variable. Important phenomena such as localized flame extinction/re-ignition and simultaneous existence of premixed/non-premixed flames in TJI-assisted combustion are also investigated.

中文翻译：

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由热活性湍流射流产生的预混和非预混火焰中的湍流-燃烧相互作用

在各种热化学条件下，在三维平面射流配置中对贫氢-空气混合物的湍流射流点火 (TJI) 辅助燃烧进行直接数值模拟。TJI 是一种新颖的点火增强方法，它通过快速连续地将稀薄和超稀薄的燃料-空气混合物暴露于高温燃烧产物中来促进它们的燃烧。完全可压缩气体动力学和物种方程用高阶有限差分方法求解。氢-空气反应通过详细的化学动力学机制进行模拟。此处使用火焰热释放、温度、物质浓度和新定义的进程变量在不同条件下研究 TJI 系统中的湍流-燃烧相互作用。