Quantification of resolution and noise effects on thermal dissipation measurements in turbulent non-premixed jet flames
Quantification of resolution and noise effects on thermal dissipation measurements in turbulent non-premixed jet flames
复制标题
湍流非预混射流火焰中分辨率和噪声对热耗散测量影响的量化
DOI：
10.1016/j.proci.2006.07.242
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发表时间：
2007
影响因子：
3.4
通讯作者：
N. Clemens
中科院分区：
文献类型：
--
作者：
Guanghua Wang;R. Barlow;N. Clemens
采用一维线瑞利测温技术研究了空间分辨率和噪声对湍流非预混CH 4/H2/N2射流火焰热耗散的影响。测量温度场的高信噪比和空间分辨率使得能够确定在每个火焰位置处获得的1-D温度耗散谱中的截止波数。从这个截止推断出的局部尺度类似于无反应流中的巴彻勒尺度。在这里研究的火焰中的下游位置，它是一致的巴彻勒尺度的基础上使用当地雷诺数的标度律的估计。光谱截止信息用于设计数据分析方案，以确定平均热耗散。层流火焰测量用于表征实验噪声和校正湍流火焰结果中的噪声引起的表观耗散。这些实验确定的分辨率和噪声校正技术相结合，给出基本上完全解决和无噪声的平均散热测量。本文还讨论了利用高分辨率一维瑞利成像测量的光谱结果来设计基于拉曼的混合分数耗散测量的滤波方案的前景。
One-dimensional (1-D) line Rayleigh thermometry is used to investigate the effects of spatial resolution and noise on thermal dissipation in turbulent non-premixed CH4/H2/N2jet flames. The high signal-to-noise ratio and spatial resolution of the measured temperature field enables determination of the cutoff wavenumber in the 1-D temperature dissipation spectrum obtained at each flame location. The local scale inferred from this cutoff is analogous to the Batchelor scale in nonreacting flows. At downstream locations in the flames studied here, it is consistent with estimates of the Batchelor scale based on the scaling laws using local Reynolds numbers. The spectral cutoff information is used to design data analysis schemes for determining mean thermal dissipation. Laminar flame measurements are used to characterize experimental noise and correct for the noise-induced apparent dissipation in the turbulent flame results. These experimentally determined resolution and noise correction techniques are combined to give measurements of the mean thermal dissipation that are essentially fully resolved and noise-free. The prospects of using spectral results from high-resolution 1-D Rayleigh imaging measurements to design filtering schemes for Raman-based measurements of mixture fraction dissipation are also discussed.