Computational and Experimental Study of Oxygenated Hydrocarbon Fuel Chemistry in Non-premixed Flames

非预混火焰中含氧烃燃料化学的计算和实验研究

• 批准号: 1133211
• 负责人: Lisa Pfefferle
• 金额: $ 32.5万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-10-01 至 2014-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1133211&HistoricalAwards=false
• 关键词: Computational; Experimental; Study; Oxygenated; Hydrocarbon

1133211PfefferleIntellectual Merit: Plants are about 50 % oxygen by weight. Thus as society inevitably moves from fossil fuels towards renewable fuels, the oxygen content of combustion fuels will increase. The presence of oxygenated hydrocarbons in the fuel introduces important combustion science and public health issues that are addressed by the proposed research. First, oxygenates may reduce emissions of soot particles. Second, they can also increase emissions of other toxic combustion byproducts such as aldehydes. In order to rationally optimize soot reductions while minimizing air toxics emissions, we need to understand the chemical mechanisms of fuel decomposition and aromatic hydrocarbon formation for oxygenates. The number of oxygenates that can be made from vegetation is large, and the sooting tendencies and fuel decomposition products vary greatly as a function of oxygenate structure; thus strictly empirical approaches for choosing among them are not reliable. A strategy that analyzes a large number of oxygenated fuels and leads to methods that can predict mechanisms and reactivity from fuel structure is needed. Although the combustion chemistry of hydrocarbons and some small oxygenates has been widely studied, little is known for most oxygenated hydrocarbons. We propose a novel approach that is based on rapid, on-line species measurements and computational simulations in co-flow flames where a small amount of the oxygenated fuel is added to a base fuel of methane. The base methane flame is has been well characterized and computations provide good agreement with experimental species measurements. Our strategy involving perturbation of a well-characterized system enables high-quality measurements and also facilitates simulations because the solutions from previously computed base methane flames can be used as a starting estimate for all of the doped flames. Importantly, our methods compare the fate of oxygenated fuel species under identical flame conditions emphasizing differences in chemical mechanisms over other factors.In earlier work we validated this methodology for regular hydrocarbons including heptanes, hexenes, hexadienes, cycloalkanes and aromatics. Here we will extend it to 100+ oxygenated hydrocarbons with up to 20 carbon atoms. Our results will provide an important comparison to other studies of oxygenates combustion chemistry, most of which use premixed flames and a limited number of oxygenated fuel structures. The analysis of a wide range of structures is required for development of structure/reactivity relationships allowing robust mechanism testing and a rational basis for oxygenated fuel selection to optimize emissions benefits.Broader Impacts: Our work sets the stage for cleaner engine design and renewable fuels utilization by expanding the database to oxygenated hydrocarbons, and by providing rational correlation and extrapolation data for the effect of fuel structure on soot production and possible toxic oxygenated emissions. We will collaborate with local industry to facilitate this. We have provided detailed results from our previous studies to numerous groups around the world who have used them to test computational models. The databases generated here will be archived for direct access to researchers around the world. Undergraduate students have participated in our previous research and will perform laboratory modules related to this project. We will also involve students from local non-PhD granting colleges and high schools in our work and helping them develop research projects at their home institutions and to interest them in continuing study in the sciences.

1133211PFEFFERFERLEINTLECTUAL FEARIT：植物的重量约为50％的氧气。 因此，随着社会不可避免地从化石燃料转向可再生燃料，燃烧燃料的氧含量将增加。 燃料中的氧化碳氢化合物的存在引入了拟议的研究解决的重要燃烧科学和公共卫生问题。 首先，氧化物可以减少烟灰颗粒的排放。 其次，它们还可以增加其他有毒燃烧副产物（如醛）的排放。 为了合理地优化烟灰的减少，同时最大程度地减少了空气毒物的排放，我们需要了解燃料分解的化学机制和芳族烃的形成。可以用植被制成的氧化物数量很大，而烟雾趋势和燃料分解产物的变化差异很大，这是氧化结构的函数。因此，在其中进行严格的经验方法是不可靠的。需要分析大量氧化燃料的策略，并导致可以预测燃料结构的机制和反应性的方法。尽管碳氢化合物和一些小氧化酸盐的燃烧化学已被广泛研究，但对于大多数氧化烃而言，鲜为人知。 我们提出了一种新的方法，该方法基于共同流火焰中快速的，在线物种的测量和计算模拟，其中将少量的含氧燃料添加到甲烷的碱燃料中。基础甲烷火焰的表征很好，计算与实验物种测量值良好。 我们涉及良好特征系统扰动的策略可以实现高质量的测量，并促进模拟，因为先前计算的基础甲烷火焰的溶液可以用作所有掺杂火焰的起始估计。重要的是，我们的方法比较了在相同的火焰条件下，强调化学机制在其他因素上的差异的命运。在这里，我们将其扩展到具有多达20个碳原子的100多种氧化烃。我们的结果将与其他氧化燃烧化学的研究提供重要的比较，其中大多数使用预混合火焰和有限数量的氧化燃料结构。 建立结构/反应性关系需要进行多种结构的分析，从而允许稳健的机制测试以及含氧燃料选择的合理基础，以优化排放效果。BROADER的影响：我们的工作为清洁发动机设计和可再生燃料利用而通过为燃料型的植入型植入和燃料的生产而扩展效应的效果，并为植入型的生效造型，并为植入型的生效造型而进行，并为燃料的生产效应提供了额外的发展。并可能有毒的氧化排放。我们将与当地行业合作，以促进这一点。 我们已经为世界各地的众多小组提供了使用它们来测试计算模型的详细结果。 此处生成的数据库将被存档，以直接访问世界各地的研究人员。本科生已经参加了我们以前的研究，并将执行与该项目相关的实验室模块。我们还将让来自当地非PHD授予大学和高中的学生参与我们的工作，并帮助他们在本机构开发研究项目，并让他们感兴趣，以继续在科学领域进行研究。