Studies of the Compositional and Temperature Effects on the Optical Properties of Flame Soot

摘要Charalampopoulos 9528598 拟议的研究的目的是研究的化学成分，温度和/或微观结构上的烟灰的折射率的影响。 拟议的研究包括非现场和现场测量。 在非原位研究中，将从预混的丙烷/氧气和乙炔/氧气火焰中收集颗粒，并形成光滑的颗粒。 将分析这些小球的碳/氢比，并通过椭圆偏振测量法测定它们在0.30 - 10 mm波长范围和25 - 250 ℃温度范围内的折射率。 通过校正空隙率效应，将确定构成颗粒表面的颗粒的折射率。 对相同火焰的现场研究，包括散射、消光和偏振测量，将用于获得颗粒直径、初级颗粒/附聚物的数量、附聚物的数量和初级颗粒的折射率。 聚集体的已知配置和折射率将被添加到CO/空气扩散火焰，以测试实验和数据反演方法。 通过这项调查，PI希望能够解释烟灰颗粒的非球形度，使用直链团聚体测试原位研究的方法，比较原位和非原位方法获得的折射率，并确定确定烟灰折射率的关键参数。

Abstract Charalampopoulos 9528598 The objectives of the proposed research is to study the effects of chemical composition, temperature and/or microstructure on the refractive indices of soot. The proposed studies involve both ex-situ and in-situ measurements. In the ex-situ studies particles will be collected from premixed propane/oxygen and acetylene/oxygen flames and formed into smooth pellets. These pellets will be analyzed for their carbon/hydrogen ratios and from ellipsometric measurements their refractive indices will be determined in the wavelength range 0.30 - 10 mm and for the temperature range 25 to 2500C. By correcting for voidage effects, the refractive indices of the particles which constitute the pellet surfaces will be determined. In-situ studies on the same flames, consisting of scattering, extinction and polarization measurements, will be used to obtain particle diameters, number of primary particles/agglomerate, number of agglomerates and the refractive indices of the primary particles. Aggregates of known configuration and refractive indices will be added to a CO/Air diffusion flame in order to test the experimental and data inversion approaches. Through this investigation the PI hopes to be able to account for the non-sphericity of the soot particles, test the methodology of the in-situ studies using straight-chain agglomerates, compare refractive indices obtained by the in-situ and ex-situ methods, and identify the critical parameters in determining soot refractive indices.