CAREER: Low-Temperature Plasma Assisted Combustion of Oxygenated Fuels for Cleaner and Sustainable Mobility

同时开发电动汽车，以及使用可再生生物燃料的下一代发动机，已被证明是满足能源需求和提高交通部门未来可持续性的有效战略。然而，事实证明，在发动机的整个运行领域，在高度燃料贫化的条件下，用表现出大量含氧组分的燃料实现可靠的燃烧是一项技术挑战。低温等离子体(LTP)被认为是克服这一障碍的一种使能技术，因为它们被证明具有增强燃烧、提供快速气体加热和促进火核生长的能力。但是，在等离子体机械效应和基本燃烧现象之间的相互作用以有效地结合LTP和生物燃料的利用方面，仍然存在知识差距。利用为等离子体辅助燃烧(PAC)研究量身定做的独特实验平台和建模工具，该项目旨在揭示这些化学基础，这些基础可以展示增强的化学反应能力、改进的能量提取和点火，以及减少污染物的形成。该项目的成果将与学术界和工业界公开分享，以支持LTP创新，并对车辆、航空航天和能源相关应用的燃烧工程产生立竿见影的影响，对经济全球化和发展中经济体产生重大好处。为了整合LTP燃烧研究和教育，该项目将：(1)利用以游戏为基础的学习，逐步使本科生/研究生课程引入新知识；(2)参与K-12推广计划，扩大未被充分代表的STEM学生的参与；以及(3)通过制作新的动画视频向公众传播研究成果，强调能源可持续发展的重要性，同时教育其社会、政治和经济影响。基于LTP的技术对于推动下一代内燃机转向可再生生物燃料和稀燃策略至关重要。该项目解决了对等离子体对燃烧反应性和点火特性的影响缺乏基本了解的问题，并增加了对含氧燃料的新的重视。这项工作也为LTP在改善燃烧工程方面的优点提供了新的证明。这些贡献将通过研究LTP等离子体对含氧燃料的低温燃烧(LTC)反应动力学和点火特性的影响，以及随后对污染物形成和稀释燃烧反应性的影响来实现。结果将通过等离子体耦合实验设备和数值模型来展示，以测量关键的化学物种和燃烧指标，并模拟重要的反应，以阐明以下方面的理解：(1)基于氧官能度的LTP对一系列含氧燃料的LTC化学反应性的改变；(2)在存在残余气体组分和污染物形成动力学的情况下LTC反应性的随后改变；(3)含氧燃料的点火和放热特性向贫油和稀燃条件的改变；以及(4)为预测模拟工具开发PAC特有的动力学机制。这一贡献意义重大，因为预计它将构成目前缺乏证明通过LTP改变高辛烷值含氧燃料化学反应性的能力的研究进展。最终，这项研究将支持LTP作为一项技术，使先进的压燃式发动机的反应性控制成为可能，并推动未来可再生生物燃料的设计，以实现可持续的移动未来。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Concurrent development of electric vehicles, along with next-generation engines using renewable biofuels has shown to be an effective strategy to meet the energy demands and improve the future sustainability of the transportation sector. However, achieving reliable combustion with fuels that exhibit a large selection of oxygenated components, at highly fuel-lean conditions, across the operational domain of the engine has proven a technological challenge. Low-temperature plasmas (LTP) are seen as an enabling technology to overcome this barrier, due to their demonstrated ability to enhance combustion, provide fast-gas heating and facilitate flame kernel growth. But there remains a knowledge gap on the interaction between plasmachemical effects and the basic combustion phenomenon to effectively couple the utilization of LTP and biofuels. Leveraging unique experimental platforms and modeling tools tailored for plasma-assisted combustion (PAC) research, this project aims to uncover these chemical fundamentals that could demonstrate enhanced chemical reactivity, improved energy extraction and ignition, with reduced pollutant formation. The results from this project will be shared openly with both academia and industry to support LTP innovation and have an immediate impact on combustion engineering for vehicular, aerospace and energy-related applications, with overarching benefits towards economic globalization and developing economies. To integrate LTP combustion research and education, this project will: (1) leverage game-based learning to progressively engage the undergraduate/graduate curriculum to introduce new knowledge; (2) engage with a K-12 outreach program to broaden the participation of underrepresented STEM students; and (3) disseminate research findings to the general public by developing a new animation video with emphasis on the importance of energy sustainability, while educating on its social, political and economic implications. LTP-based technologies are essential to advance next-generation internal combustion engines toward renewable biofuels and dilute-burn strategies. This project addresses the lack of fundamental understanding of plasmachemical effects on combustion reactivity and ignition characteristics, and adds a new emphasis on oxygenated fuels. This work also provides a new demonstration of the merits of LTP to improve combustion engineering. These contributions will be achieved through a study of LTP plasmachemical effects on the low-temperature combustion (LTC) reaction kinetics of oxygenated fuels and ignition characteristics, and subsequent implications on pollutant formation and dilute-burn reactivity. Outcomes will be demonstrated through plasma-coupled experimental facilities and numerical models to measure key chemical species and combustion metrics, and simulate important reactions to elucidate an understanding of: (1) the alteration of LTC chemical reactivity by LTP for a range of oxygenated fuels based on oxygen functionality; (2) subsequent alteration of LTC reactivity in the presence of residual gas components and pollutant formation kinetics; (3) the alteration of ignition and heat-release characteristics of oxygenated fuels toward fuel-lean and dilute-burn conditions; and (4) development of a PAC-specific kinetic mechanism for predictive simulation tools. This contribution is significant because it is expected to constitute a progression of research that is currently lacking to demonstrate the ability to alter the chemical reactivity of high-octane oxygenated fuels through LTP. Ultimately, this research will support LTP as a technology to enable reactivity control for advanced compression-ignition engines and drive future designs toward renewable biofuels to achieve a sustainable future for mobility.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.