Heat flux measurements in stagnation point methane/air flames with thermographic phosphors
Heat flux measurements in stagnation point methane/air flames with thermographic phosphors
复制标题
使用热成像荧光粉测量停滞点甲烷/空气火焰中的热通量
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
B. Atakan
中科院分区：
文献类型：
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作者：
M. Salem;S. Staude;U. Bergmann;B. Atakan
利用热像荧光粉的光致磷光研究了近一维平板预混火焰的壁面温度和热流密度。研究的火焰为当量比为φ = 1、φ = 0.75和φ = 1.25的甲烷/空气层流火焰。火焰以驻点的方式燃烧着，靠在一个水冷的盘子上。该板的中心部分是氧化铝陶瓷板，其从两侧涂覆有铬掺杂的氧化铝（红宝石），并且用Nd：YAG激光器或绿色发光二极管（LED）阵列激发，以从两侧测量壁温度，从而测量来自火焰的热通量率。气体的出口速度在0.1至1.2 m/s之间变化。燃烧器到板的距离（H）为燃烧器出口直径（d = 30 mm）的0.5至2倍。测量的热通量率指示火焰稳定机制从燃烧器稳定到滞止板稳定火焰的变化。将结果与一维驻点流的模拟结果进行了比较，并给出了详细的反应机理。为了验证该模型，气相温度测量的化学计量驻点火焰的OH-LIF。结果表明，火焰稳定机制和与它的热通量从低到高的质量通量变化。这种几何形状可能非常适合进一步研究的基本火焰壁相互作用。
Light-induced phosphorescence from thermographic phosphors was used to study the wall temperatures and heat fluxes from nearly one-dimensional flat premixed flames. The investigated flames were stoichiometric, lean and rich laminar methane/air flames with equivalence ratios of φ = 1, φ = 0.75 and φ = 1.25 at ambient pressure. The flames were burning in a stagnation point arrangement against a water-cooled plate. The central part of this plate was an alumina ceramic plate coated from both sides with chromium-doped alumina (ruby) and excited with a Nd:YAG laser or a green light-emitting diode (LED) array to measure the wall temperature from both sides and thus the heat flux rate from the flame. The outlet velocity of the gases was varied from 0.1 to 1.2 m/s. The burner to plate distance (H) ranged from 0.5 to 2 times the burner exit diameter (d = 30 mm). The measured heat flux rates indicate the change of the flame stabilization mechanism from a burner stabilized to a stagnation plate stabilized flame. The results were compared to modeling results of a one-dimensional stagnation point flow, with a detailed reaction mechanism. In order to prove the model, gas phase temperatures were measured by OH-LIF for a stoichiometric stagnation point flame. It turns out that the flame stabilization mechanism and with it the heat fluxes change from low to high mass fluxes. This geometry may be well suited for further studies of the elementary flame wall interaction.