BRIGE: Combustion Intermediate Species Measurement Using Microwave and Laser Diagnostics

1032523 ZhangThe的总体目标，这扩大参与研究启动工程（BRIGE）计划赠款是创造新的微波和激光诊断技术的定量中间物种测量化石燃料和生物燃料燃烧在大气压和更高的压力，并教育学生的基本激光物理学，燃烧科学和能源相关技术。 目前，化石燃料的燃烧提供了全球消耗的约85%的能源，并产生了大部分的空气污染物。生物燃料是一种可替代的可再生能源，它的燃烧减少了一些污染物的排放。原则上，所有燃料的燃烧都是通过许多基本反应步骤进行的。原子、分子自由基和复杂的分子物种在控制化学过程网络方面起着主导作用，其中许多物种还没有被现有的诊断技术很好地理解，因为这些物种大多数是短暂的，浓度很低。特别是，生物燃料燃烧由于极其复杂的化学过程而知之甚少，这挑战了诊断工具的局限性，并使数值模拟异常困难。利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更环保的设备和设施的革命性发展，有助于解决全球气候变化等经济和社会问题。智力成果在这项研究中，新的微波和激光诊断技术，来自局域共振增强多光子电离（REMPI）的共振相干微波散射和处于里德伯态的分子的光电离将用于识别中间痕量物质，其在大气压和更高压力下燃烧中的火焰区中和周围的灵敏度为~100 ppb（十亿分之一）水平。要遵循的物种包括H和O原子，CH 3和HCO自由基，和复杂的异构体分辨分子C6 H6和C7 H8等。该技术使用一个或两个频率可调谐激光器选择性地产生电离的特定物种和共振相干微波散射定量检测物种浓度的演变，通过电离区域内的电子。这些特征联合收割机提供了高精度、猝灭稳定的电离光谱，其可以在高达并包括操作燃烧器压力的压力下定量和原位测量物质的浓度。新的诊断技术在测量中间组分中的应用将极大地推进我们对基本燃烧现象的理解。在充分表征的条件下对生物燃料燃烧的系统诊断评价将提供基本的物种信息，其可用于验证和校准生物燃料燃烧的现有化学动力学模型，更广泛的影响拟议中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、交通运输等依赖燃烧的行业。计划中的研究得到了详细的教育计划的补充，该计划将对下一代劳动力的教育产生广泛的影响，并将对广泛的社区教育产生积极影响。作为拟议教育工作的一部分，PI将直接根据研究开发两门课程。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现实世界测试之间的差距方面获得关键经验。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，工程计划中的女性，高中介绍工程系统（HITES）和中学介绍工程计划（MITE），将拟议的研究活动暴露给当地公立学校和学校，以吸引感兴趣的高中学生报名参加科学和工程课程。PI和在这个项目中雇用的学生将在这些活动的发言人和导师。

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.