Autoignition of Primary Reference Fuels and Blends with Ethanol and Dimethly Ether

1404026 Seshardri，Kalyanasundaram标题：主要参考燃料的自燃以及与乙醇和二甲醚的混合物燃烧在许多工业和工程应用中非常重要，例如汽车发动机和发电厂。这项研究的目标是提供有助于开发设计有效利用化石燃料和二氧化碳中性交通燃料的发动机所需技术的科学知识。所提出的工作包括两个实验，其结果可以验证点火现象的理论/数学分析。致力于该项目的研究生为国家的STEM(科学、技术、工程和数学)工作做出了贡献。自燃是所有长链烃和一些含氧燃料在发动机中存在的固有特性。发动机的有效运行取决于这一特性。为了对层流非预混流动中正庚烷、异辛烷、乙醇、二甲醚的自燃有一个基本的了解，将进行一项全面的实验、计算和分析研究。选择烷烃正庚烷和异辛烷是因为它们被指定为主要的参考燃料，并被认为是柴油和汽油的替代品。将测量自动点火的临界条件。计算将使用详细的化学方法进行。这项研究的很大一部分将致力于使用速率比渐近技术来获得可用于预测自燃的解析表达式。预计主要成果将是燃料自燃的实验数据，测试的化学动力学机制，以及可用于计算流体动力学程序的中高温区域自燃预测的解析表达式。这项研究将对自燃作为一种分链/断链过程有一个明确的基本理解，该过程涉及燃料在不同温度范围内对特定自由基的竞争。这项研究将为分析自燃提供新的数学方法。这些方法都有其边界层理论和奇异摄动分析的基础。因此，它们有望在分析流体力学、热科学和化学科学中的问题时有更广泛的用途。

1404026Seshardri, KalyanasundaramTitle: Autoignition of Primary Reference Fuels and Blends with Ethanol and Dimethly EtherCombustion is important in many industrial and engineering applications, such as automotive engines and power plants. The goal of this research is to provide scientific knowledge that will be useful for developing the technology required for designing engines that make efficient use of fossil fuels and carbon-dioxide-neutral transportation fuels. The proposed effort involves both experiments, with whose results theoretical/mathematical analysis of the ignition phenomena can be validated. Graduate students working on the project contribute to the nation's STEM (science, technology, engineering, and mathematics) work force.Autoignition is an inherent property of all long-chain hydrocarbons and some oxygenated fuels as they occur in engines. Efficient operation of engines depends crucially on this property. A comprehensive experimental, computational and analytical study will be carried out with the goal of obtaining a fundamental understanding of autoignition of n-heptane, iso-octane, ethanol, dimethyl ether, in laminar non-premixed flows. The alkanes n-heptane and iso-octane are selected because they are designated as primary reference fuels and are considered as surrogates of Diesel and gasoline. Critical conditions of autoignition will be measured. Computations will be performed using detailed chemistry. A significant part of the research will be devoted to employing rate-ratio asymptotic techniques to obtain analytical expressions that can be used to predict autoignition. The key outcomes are expected to be, experimental data on autoignition for the fuels, tested chemical kinetic mechanisms, and analytical expressions for predicting autoignition in the intermediate and high temperature regimes that can be employed in computational fluid dynamic codes. The research will provide a clear fundamental understanding of autoignition as a chain-branching/chain-breaking process which involves the competition of the fuels for specific radicals in different temperature regimes. The research will provide new mathematical techniques for analyzing autoignition. These techniques have their foundation in boundary layer theory and singular perturbation analysis. Therefore they are expected to have a much wider use in analyzing problems in fluid mechanics, thermal sciences and chemical sciences.