Toward a precise modeling for wall chemical effects in flame-wall interactions, radical adsorption on different wall surfaces are directly evaluated through a newly-developed molecular beam scattering technique using a non-equilibrium plasma–driven beam source as well as an ultra-high vacuum chamber. Firstly, sensitivities of adsorption rates for each radical species to the wall chemical effect are examined through a series of numerical simulations with detailed gas/surface chemistry for a methane-air premixed flame. Since H-atom has a higher diffusivity and its adsorption significantly inhibits a chain branching reaction of H + O₂= O + OH, H is considered to be the most influential radical on the flame characteristics such as heat release rate or CO emission if compared to OH, O and CH₃. Based on the sensitivity analysis, H adsorptions are quantified for quartz and SUS321 surfaces with the plasma molecular beam scattering measurements. It is confirmed that H atomic beam can be successfully produced through the plasma dissociation of H₂ molecules. Then, the produced H beam is irradiated onto quartz and SUS321 surfaces at different wall temperatures T_w. It is found that H is adsorbed on the quartz and SUS321 surfaces, and reaction probabilities of H P_H has its maxima at T_w ∼673 K for both surfaces. This is probably because that the recombination rate increases as T_w increases, while the desorption rate is also promoted and overcomes the recombination rate at T_w > 673 K. The P_H for the SUS321 is in agreement with that in our previous combustion experiments and more precise value can be obtained by the present method.

为了精确建模火焰壁相互作用中的壁化学效应，可通过使用非平衡等离子体驱动束源以及超高真空的新开发的分子束散射技术直接评估不同壁表面上的自由基吸附室。首先，通过一系列数值模拟，对甲烷-空气预混火焰的详细气体/表面化学性质进行了一系列数值模拟，考察了每种自由基对壁化学效应的吸附速率的敏感性。由于H原子具有较高的扩散性，并且其吸附显着抑制了H + O ₂的链支化反应= O + OH，如果与OH，O和CH ₃相比，则H被认为是对火焰特性（如放热率或CO排放）的影响最大的基团。基于敏感性分析，通过等离子体分子束散射测量，可以量化石英和SUS321表面的H吸附量。已经证实，通过H ₂分子的等离子体解离可以成功地产生H原子束。然后，将产生的H束以不同的壁温T _w照射到石英和SUS321表面上。发现H吸附在石英和SUS321表面上，并且H P _H的反应概率在T _w处具有最大值两面约673K。这可能是因为重组率随着牛逼_W¯¯增加，而解吸速率也促进并克服了重组率在牛逼_{w ^}  > 673 K的P _{^ h}为SUS321是同意与我们以前的燃烧实验通过本方法可以获得更精确的值。