BRIGE: Combustion Intermediate Species Measurement Using Microwave and Laser Diagnostics

BRIGE：使用微波和激光诊断进行燃烧中间物质测量

• 批准号: 1032523
• 负责人: Zhili Zhang
• 金额: $ 17.5万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2015-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1032523&HistoricalAwards=false
• 关键词: BRIGE; Combustion; Intermediate; Species; Measurement

1032523ZhangThe overall goal of this Broadening Participation Research Initiation Grants in Engineering (BRIGE) plan is to create novel microwave and laser diagnostic techniques for quantitative intermediate species measurements in fossil fuel and biofuel combustions at atmospheric and higher pressures and to educate students on the fundamental laser physics, combustion science and energy-related technologies. Combustion of fossil fuels currently provides about 85% of the energy consumed worldwide and generates the majority of the airborne pollutants. Biofuel is an alternative renewable energy source and its combustion reduces emission of some pollutants. In principle, combustion of all fuels proceeds through a multitude of elementary reaction steps. Atomic, molecular radical and complex molecular species play dominant roles in controlling the networks of chemical processes, many of which are not well understood by existing diagnostic techniques since most of those species are transient and at low concentrations. In particular, biofuel combustion is poorly understood due to the enormously complicated chemical processes, which challenge the limitations of diagnostic tools and make numerical simulations exceptionally difficult. Systematic study of the intermediate chemical compounds and their reactions in fossil fuel and biofuel combustions using novel diagnostic techniques may result in revolutionary development of more energy efficient and environmentally friendly devices and facilities, contributing to the solution of economical and societal issues such as global climate change.Intellectual Merit In this research novel microwave and laser diagnostic techniques, resonant coherent microwave scattering from localized Resonance-Enhanced Multi-Photon Ionization (REMPI) and photoionization of molecules at Rydberg states will be used to identify intermediate trace species with a sensitivity at ~100 ppb (parts per billion) level in and around the flame zone in combustions at atmospheric and higher pressures. Species to be followed include H and O atoms, CH3 and HCO radicals, and complex isomer-resolved molecules C6H6 and C7H8 etc. The techniques use one or two frequencytunable lasers to selectively generate ionization of a specific specie and resonant coherent microwave scattering to quantitatively detect the evolution of species concentration through the electrons inside the ionization region. These features combine to offer a high-precision, quenching-robust ionization spectroscopy, which can quantitatively and in-situ measure concentrations of the species at pressures up to and including operating combustor pressures. The application of the novel diagnostic techniques in measuring the intermediate species will greatly advance our understanding of fundamental combustion phenomena. A systematic diagnostic evaluation of biofuel combustions under well-characterized conditions will provide fundamental species information that can be used to validate and calibrate existing chemical kinetic models of biofuel combustions, possibly leading to improved combustion efficiency and more versatile and less polluting biofuel sources and devices.Broader Impact The proposed research will develop a new capability that may have broad impacts on many fields of engineering such as aerospace, mechanical, transportation and other industries that rely on the combustion. The planned research is complemented by a detailed educational plan that will have broad impacts on teaching the next generation of the workforce and the outreach efforts that will have a positive influence toward broad community education. As a part of the proposed educational efforts, the PI will develop two courses directly based on the research. The laboratory work will be designed for the courses to facilitate a more open-ended approach to engineering education upon which the students will gain critical experience in learning how to apply theory and bridge gaps between theory and real-world tests. Graduate students working in this project will target the underrepresented or minority groups. We will expose the proposed research activities to both local public schools and schools from underrepresented communities through the university's existing K-12 outreach program, Women in Engineering Program, the High School Introduction to Engineering System (HITES) and the Middle School Introduction to Engineering Program (MITE) to attract interested high school students to enroll in science and engineering programs. The PI and students employed in this project will be speakers and mentors at these events.

1032523张本“扩大参与研究启动资助工程”（bridge）计划的总体目标是创建新的微波和激光诊断技术，用于在大气和高压下对化石燃料和生物燃料燃烧进行定量测量，并教育学生了解基本的激光物理、燃烧科学和能源相关技术。化石燃料的燃烧目前提供了全球约85%的能源消耗，并产生了大部分空气污染物。生物燃料是一种可替代的可再生能源，其燃烧可减少一些污染物的排放。原则上，所有燃料的燃烧都要经过许多基本反应步骤。原子、分子自由基和复杂分子物种在控制化学过程网络中起着主导作用，其中许多是现有诊断技术无法很好地理解的，因为大多数这些物种是短暂的和低浓度的。特别是，由于生物燃料的化学过程极其复杂，人们对其燃烧知之甚少，这挑战了诊断工具的局限性，使数值模拟变得异常困难。使用新的诊断技术系统地研究化石燃料和生物燃料燃烧中的中间化合物及其反应，可能会导致更节能和环保的设备和设施的革命性发展，有助于解决经济和社会问题，如全球气候变化。在这项研究中，新的微波和激光诊断技术，共振相干微波散射从局部共振增强多光子电离（REMPI）和分子的光子电离在里德堡态将被用于识别中间痕量物质的灵敏度在~100 ppb（十亿分之一）水平在大气和高压下燃烧的火焰区和周围。研究对象包括H和O原子、CH3和HCO自由基、C6H6和C7H8等同分异构体的复杂分子。该技术使用一个或两个频率可调的激光器选择性地产生特定物质的电离和共振相干微波散射，通过电离区域内的电子定量检测物质浓度的演变。这些特点结合起来，提供了高精度，淬灭鲁棒电离光谱，可以定量和原位测量压力下的物质浓度，包括工作燃烧室压力。新诊断技术在测量中间物质中的应用将极大地促进我们对基本燃烧现象的理解。在良好表征条件下对生物燃料燃烧进行系统的诊断评估将提供基本的物种信息，可用于验证和校准生物燃料燃烧的现有化学动力学模型，可能导致提高燃烧效率和更通用、更少污染的生物燃料来源和设备。更广泛的影响拟议的研究将开发一种新的能力，可能对许多工程领域产生广泛的影响，如航空航天、机械、运输和其他依赖燃烧的行业。计划中的研究还辅之以一项详细的教育计划，该计划将对下一代劳动力的教学产生广泛影响，并对广泛的社区教育产生积极影响。作为提议的教育努力的一部分，PI将直接以研究为基础开发两门课程。实验室工作将为课程设计，以促进更开放的工程教育方法，学生将在学习如何应用理论和弥合理论与实际测试之间的差距方面获得重要经验。在这个项目中工作的研究生将针对代表性不足或少数群体。我们将通过大学现有的K-12外展计划、女性工程计划、高中工程系统介绍（HITES）和中学工程介绍计划（MITE）向当地公立学校和代表性不足的社区的学校展示拟议的研究活动，以吸引感兴趣的高中生参加科学和工程计划。在这个项目中雇用的PI和学生将在这些活动中担任演讲者和导师。