X-ray computed tomography for flame-structure analysis of laminar premixed flames
X-ray computed tomography for flame-structure analysis of laminar premixed flames
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DOI：
10.1016/j.combustflame.2018.11.015
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发表时间：
2019-02-01
影响因子：
4.4
通讯作者：
Ihme, Matthias
中科院分区：
文献类型：
--
作者：
Boigne, Emeric;Muhunthan, Priyanka;Ihme, Matthias
定量X射线计算机断层扫描（XCT）诊断反应流的开发和演示应用预混火焰在开放和光学不可访问的几何形状。一个实验室的X射线扫描仪被用来调查甲烷/空气火焰，稀释氪作为一种惰性的不透射线的示踪气体。考察了采集速率和示踪气体浓度对信噪比的影响。结果表明，统计收敛的三维衰减测量可以得到有限的影响，从示踪气体和在一个可接受的采集时间内。具体方面的断层重建和实验过程进行检查，特别强调实验的不确定性的量化。提出了一种由X射线衰减测量确定密度和温度的方法。这些实验的补充一维和多维计算，以量化氪对火焰行为的影响。为了证明XCT的光学不可接近的火焰的优点，在一个复杂的火焰几何形状的管状限制进行测量。使用一个coflow提供一个均匀的示踪气体浓度，以提高定量温度评价。这些测量结果表明，XCT火焰结构分析和多维温度测量使用实验室X射线系统的可行性。进一步改善这种诊断的机会进行了讨论。(C)2018燃烧院爱思唯尔公司出版All rights reserved.
Quantitative X-ray computed tomography (XCT) diagnostics for reacting flows are developed and demonstrated in application to premixed flames in open and optically inaccessible geometries. A laboratory X-ray scanner is employed to investigate methane/air flames that were diluted with krypton as an inert radiodense tracer gas. Effects of acquisition rate and tracer gas concentration on the signal-to-noise ratio are examined. It is shown that statistically converged three-dimensional attenuation measurements can be obtained with limited impact from the tracer gas and within an acceptable acquisition time. Specific aspects of the tomographic reconstruction and the experimental procedure are examined, with particular emphasis on the quantification of experimental uncertainties. A method is developed to determine density and temperature from the X-ray attenuation measurements. These experiments are complemented by one- and multi-dimensional calculations to quantify the influence of krypton on the flame behavior. To demonstrate the merit of XCT for optically inaccessible flames, measurements of a complex flame geometry in a tubular confinement are performed. The use of a coflow to provide a uniform tracer-gas concentration is shown to improve the quantitative temperature evaluation. These measurements demonstrate the viability of XCT for flame-structure analysis and multi-dimensional temperature measurements using laboratory X-ray systems. Further opportunities for improving this diagnostic are discussed. (C) 2018 The Combustion. Institute. Published by Elsevier Inc. All rights reserved.