CAREER: Multi-isotopologue absorption spectroscopy for hydrogen-carrier and nitrogen-based low-carbon energy

运输和发电部门的下一代燃料预计将包括传统燃料（碳基）和可再生或替代燃料（氢基或氮基）。然而，这种未来燃料及其混合物的反应途径还没有得到很好的理解，这阻止了它们部署到低碳、更省油的新一代发动机（包括涡轮机、汽车、喷气和火箭发动机）中。在这项工作中，一种新的激光诊断方法，旨在测量同位素标记的燃料混合物中的多种同位素，用于研究基本的化学反应途径，包括污染物的形成。该项目的成功完成将提供（1）一种广泛适用的新型测量技术，将推进基础燃烧和大气科学研究，以及（2）对这些新型可再生燃料混合物中点火和污染物形成的基本化学的新见解。综合教育活动将通过开放源代码软件开发、将实验室活动纳入圣安东尼奥大学不断发展的航空航天课程以及针对圣安东尼奥和德克萨斯州下格兰德河山谷的初中和高中学生的有针对性的基于项目的外联活动，对多个级别（从中学到研究生院）的学生产生影响。本项目的研究目标是开发和探索多同位素激光吸收光谱技术在下一代低碳载氢和氮基燃料高温反应流中的测量、研究和动力学路径建模方面的应用。该技术旨在填补实验高温动力学研究中的空白，该研究通常无法明确跟踪从反应物到中间体再到产物的反应途径中的特定原子。 这项研究将使新的类别的混合碳/低碳燃料混合物的燃烧研究。据推测，该技术将提供不同燃料类型（碳基，氮基，含氧）和官能团的混合物的反应途径的新见解。与新的同位素标记的动力学模型和不确定性加权灵敏度分析相结合，该框架提供了一种新的手段，用于减少使用同位素标记的化学品进行实验所需的数量和成本。该项目中产生的新型高压和高温光谱数据和模型也将加速高超音速流、火箭推进和行星探测遥感方面的研究，为圣安东尼奥和南得克萨斯州燃烧科学以外的研究提供广泛的应用。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值进行评估来支持和更广泛的影响审查标准。

The next generation of fuels for the transportation and power generation sectors is expected to involve a mix of both traditional (carbon-based) and renewable or alternative fuels (hydrogen- or nitrogen-based). However, the reaction pathways of such future fuels and mixtures thereof are not well understood, preventing their deployment into the low-carbon, more fuel-efficient new generation of engines (including turbine, automotive, jet, and rocket engines). In this work, a novel laser diagnostic method, designed to measure multiple isotopes in isotopically-labeled fuel mixtures, is used to investigate fundamental chemical reaction pathways, including the formation of pollutants. Successful completion of the project will provide (1) a broadly applicable and novel measurement technique that will advance basic combustion and atmospheric science research and (2) new insights into the fundamental chemistry of ignition and pollutant formation in these new class of renewable fuel mixtures. Integrated education activities will impact students at multiple levels (middle school through graduate school) through open-source software development, integration of laboratory activities into The University of San Antonio’s growing aerospace curriculum, and targeted project-based outreach activities with middle school and high school students in San Antonio and the Lower Rio Grande Valley in Texas. The research objective of this project is to develop and explore applications of multi-isotopologue laser absorption spectroscopy for measurement, investigation, and modeling of kinetic pathways in high temperature reacting flows of next-generation and low-carbon hydrogen-carrier and nitrogen-based fuels. The technique is aimed at filling a gap in experimental high-temperature kinetics studies, which often cannot unambiguously track specific atoms in their reaction pathways from reactants to intermediates to products. The study will enable new classes of combustion studies for blended carbon / low-carbon fuel mixtures. It is hypothesized that the technique will provide new insights into reaction pathways for mixtures of varying fuel types (carbon-based, nitrogen-based, oxygenated) and functional groups. Paired with novel isotopically-labeled kinetic models and uncertainty-weighted sensitivity analyses, the framework provides a new means for reducing the required number and costs of experiments using isotopically-labeled chemicals. The novel high-pressure and high-temperature spectroscopy data and models generated in this project will also accelerate research in hypersonic flows, rocket propulsion, and remote sensing in planetary exploration, providing for broad applications of the research beyond combustion science for San Antonio and South Texas.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.