Research Initiation Award: Metal Additive Effects on Soot Morphology in Laminar Diffusion Flames

本实验研究了铁添加剂对层流、环状、乙烯/空气扩散火焰中碳烟颗粒形态的影响。这项工作的主要目标是确定燃烧环境中添加剂物种的状态和形态，以及它们对火焰坐标的依赖。其他需要解决的基本问题包括添加剂是否在燃烧早期或后期干预，以确定铁燃烧产物是否遮挡在烟尘相中，如果是，则检查它们作为火焰位置的函数在碳基质中的掺入情况。将通过对从不同火焰位置收集的颗粒物相进行元素分析来量化烟尘相中的铁燃烧产物的含量(如果存在)。最近开发的侵入性取样技术与透射电子显微镜结合使用，以提供火焰中颗粒相的形态和元素表征的样品。拟议的基础研究将有助于更好地理解金属添加剂对实验室烟尘形成、生长、氧化和排放的基本机制的影响，这些烟尘是由明确界定的火焰产生的。我们解决这些问题的能力可能会定义新的方法，以增强和优化燃料添加剂的使用，以抑制烟尘。

This experimental study addresses the influence of iron additives on soot-particle morphology in laminar, coannular, ethylene/air diffusion flames. The primary objective of the work is to determine both state and morphology of the additive species within the combustion environment, as well as their dependence on flame coordinates. Other fundamental issues to be addressed include whether the additive intervenes at an early or late combustion stage, to determine if iron combustion products are occluded in the soot phase, and in case they are, to examine their incorporation within the carbon matrix as a function of flame location. The incorporation of iron combustion products within the soot phase (if present) will be quantified through an elemental analysis of the particulate phase collected from various flame locations. A recently developed intrusive sampling technique winl be used in conjunction with transmission electron microscopy to provide the samples for morphological and elemental characterization of the particulate phase within the flames. The proposed fundamental research would contribute to a better understanding of the metal-additive influence on the basic mechanisms involved in the formation, growth, oxidation and emission of soot from laboratory, well-defined flames. Our ability to resolve these issues may define new ways to enhance and optimize fuel-additive use for soot suppression.