To explore the effect of H₂ addition (20 percent by volume) on stratified-premixed methane combustion in a turbulent flow, an experimental investigation on a new flame configuration of the Darmstadt stratified burner is conducted. Major species concentrations and temperature are measured with high spatial resolution by 1D Raman-Rayleigh scattering. A conditioning on local equivalence ratio (range from ϕ = 0.45 to ϕ = 1.25) and local stratification is applied to the large dataset and allows to analyze the impact of H₂ addition on the flame structure. The local stratification level is determined as Δϕ/ΔT at the location of maximum CO mass fraction for each instantaneous flame realization. Due to the H₂ addition, preferential diffusion of H₂ is different than in pure methane flames. In addition to diffusing out of the reaction zone where it is formed, particularly in rich conditions, H₂ also diffuses from the cold reactant mixture into the flame front. For rich conditions (ϕ = 1.05 to ϕ = 1.15) H₂ mass fractions are significantly elevated within the intermediate temperature range compared to fully-premixed laminar flame simulations. This elevation is attributed to preferential transport of H₂ into the rich flame front from adjacent even richer regions of the flow. Additionally, when the local stratification across the flame front is taken into account, it is revealed that the state-space relation of H₂ is not only a function of the local stoichiometry but also the local stratification level. In these flames H₂ is the only major species showing sensitivity of the state-space relation to an equivalence ratio gradient across the flame front.

为了探索湍流中H _2的添加量（按体积计20％）对分层预混合甲烷燃烧的影响，对达姆施塔特分层燃烧器的新火焰构型进行了实验研究。通过一维拉曼-瑞利散射以高空间分辨率测量主要物种的浓度和温度。上局部当比率A调理（范围从φ = 0.45〜φ = 1.25）和局部分层被施加到大的数据集，并允许分析H的影响₂除了在火焰结构。本地分层等级被确定为Δφ在最大CO质量分数的每个瞬时火焰实现位置/ΔT。由于H₂另外，H _2的优先扩散不同于纯甲烷火焰。H ₂除了扩散到形成它的反应区之外，特别是在富裕条件下，还从冷的反应混合物扩散到火焰前沿。与完全预混合的层流火焰模拟相比，在富裕条件下（ϕ = 1.05至ϕ = 1.15），H ₂质量分数在中间温度范围内显着提高。该升高归因于H _2的优先运输从流动的相邻甚至更富裕的区域进入到富裕的火焰前沿。另外，当考虑到横跨火焰前沿的局部分层时，发现H ₂的状态-空间关系不仅是局部化学计量的函数，而且是局部分层水平的函数。在这些火焰中，H ₂是唯一显示状态空间关系对整个火焰前沿的当量比梯度敏感的主要物质。