Frequency resolved interferometric detection of local density fluctuations in flames
Frequency resolved interferometric detection of local density fluctuations in flames
复制标题
火焰中局部密度波动的频率分辨干涉检测
DOI：
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发表时间：
2014
期刊：
影响因子：
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通讯作者：
J. Woisetschläger
中科院分区：
文献类型：
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作者：
Johannes Peterleithner;Florian Salcher;J. Woisetschläger
低NOx策略通常包括稀薄燃烧以降低火焰温度。在某些条件下，这种相互作用可以作为热声耦合周期性地发生，这就是为什么新的预混燃烧系统往往会有振荡的原因。不断的发展推动了使用激光测振仪测量密度波动的灵敏度。在这个实验中，一个可变几何形状的燃烧器被封闭在一个衬里里，火焰通过四个熔融的二氧化硅窗口光学地进入。通过这种火焰条件可调的燃烧器，大气模型燃烧室的腔体可以在200赫兹左右的频率下被激发。用激光测振仪干涉法、纹影显像法和OH~*/CH~*化学发光法对共振和非共振火焰条件进行了研究和比较。
Low NOx strategies usually include lean combustion in order to reduce the flame temperature. Under certain conditions, this interaction can occur periodically as thermo-acoustic coupling, a reason why new premix combustion systems tend to have oscillations. Ongoing developments have pushed the sensitivity for density fluctuation measurements using laser vibrometers. In this experiment a variable geometry burner was enclosed in a liner, with the flame optically accessible through four fused silica windows. By this burner with adjustable flame conditions the cavity of the atmospheric model combustion chamber was excitable at a frequency around 200Hz. Resonant and non-resonant flame conditions were investigated and compared by laser vibrometer interferometry, schlieren visualization and OH*/CH* chemiluminescence.