Proceedings of the Combustion Institute ( IF 3.4 ) Pub Date : 2018-07-23 , DOI: 10.1016/j.proci.2018.07.038 N.A.K. Doan , N. Swaminathan
The criterion used to define MILD combustion in non-premixed condition is analysed using Direct Numerical Simulation (DNS) of MILD combustion of methane-diluted air established with internal exhaust gas recirculation. The simulations reveal multiple interacting reaction zones in MILD combustion which are extremely different from conventional combustion. Furthermore, DNS deduced S-curves highlight the role of chemically active species. Specifically, the temperature rise is accompanied with an increase in the scalar dissipation rate of mixture fraction, which is quite contrasting to the classical S-curve from the classical flame theories. This observation is explained on a physical basis.
中文翻译:
自由基在MILD燃烧初期的作用
使用内部废气再循环建立的甲烷稀释空气的MILD燃烧的直接数值模拟(DNS),分析了用于定义非预混合条件下的MILD燃烧的标准。该模拟揭示了MILD燃烧中多个相互作用的反应区,这些反应区与常规燃烧极为不同。此外,DNS推断的S曲线突出了化学活性物质的作用。特别地,温度上升伴随着混合分数的标量耗散率的增加,这与来自经典火焰理论的经典S曲线形成鲜明对比。这种观察是在物理基础上进行解释的。