NSF-BSF: Plasma Reformed Ammonia as a Carbon Free Fuel: Study of Nanosecond-Pulsed Discharge Kinetics and Combustion Enhancement

NSF-BSF：等离子体重整氨作为无碳燃料：纳秒脉冲放电动力学和燃烧增强的研究

• 批准号: 2236512
• 负责人: Bret Windom
• 金额: $ 43.36万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-12-01 至 2025-11-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2236512&HistoricalAwards=false
• 关键词: NSF; BSF; Plasma; Reformed; Ammonia

Renewable energy systems (e.g., wind, hydro, solar) are primed to play the dominant role in supplying the world’s power, but before independence from fossil fuels can be achieved there must be cost-effective ways to store the renewable energy and utilize it in hard to decarbonize transportation sectors. Ammonia (NH3), which can be synthesized using renewable energy and can easily be stored/transported as a liquid, has garnered significant interest as a carbon-free low-cost chemical energy storage medium and potential fuel for heavy duty freight/marine applications. While the attention being paid to ammonia as an energy storage solution and fuel is warranted, its low reactivity and propensity to produce nitric oxide emissions during combustion represent critical impediments to widescale adoption. Through the joint NSF-BSF program, researchers at Colorado State University and Technion - Israel Institute of Technology are partnering to progress the scientific understanding needed to develop plasma assisted ammonia reforming strategies to enable the use of ammonia in state-of-the-art combustion devices. Key outcomes from the proposed effort include a validated ammonia-plasma chemistry model and a validated combustion simulation strategy for the plasma-reformed ammonia mixtures at engine relevant conditions. The research output will benefit both the energy and transportation sectors – industries which together account for 73% of greenhouse gas emissions worldwide – by supporting the development of high-fidelity models required to shorten the design cycles of next generation carbon-free energy conversion devices. This unique funding opportunity from NSF/BSF will help foster international collaboration leveraging the unique expertise in plasma reformation at Technion and combustion and laser diagnostics at Colorado State University and will support high impact educational and diversity building activities across borders. Findings will be shared in publications, at conferences, and will be integrated into joint undergraduate and graduate coursework at the collaborating institutions. The research will be regularly highlighted in K-12 outreach events.Preliminary plasma- and combustion-kinetic modeling by the proposal team has suggested that the ignitability and flame speed of NRP plasma reformate blends could be comparable to those of conventional fuels across a wide range of operating conditions. Detailed kinetics within the plasma reactor have been examined, including identifying the key role of the NH2 radical for reduction of NO combustion emissions. This work aims to expound upon these modeling results via experimental validation to build a foundation for future system-based development and optimization efforts. The main elements of the work plan are: (1) reformate species measurements within a newly constructed NRP plasma reactor to validate and refine existing NH3 plasma kinetic models, (2) NH2 measurements within the NRP by cavity ring-down spectroscopy (CRDS) to elucidate NH2’s role in plasma kinetics and NOx reduction, and (3) ignition delay and flame speed measurements of the resulting NH3 reformate blends at relevant conditions using a laser-ignited rapid compression machine. These efforts will address gaps in the current literature including: (1) the detailed study of the relative impact of plasma pulse frequency, amplitude, and reactor pressure/temperature on NH3 and NH3/air reformation efficiency in an NRP reactor, constituting a validation dataset for kinetic modeling efforts; (2) the first direct measurement of NH2 radical formation in ns-pulsed systems for quantitative comparison with kinetic models; and (3) the expansion of ignition delay and flame speed measurements of NH3/H2/O2/N2 reformate blends into temperature/pressure regimes that are sparse in current literature, with trace NO/NO2, varying equivalence ratio, and induced turbulence, providing an invaluable dataset to support NH3 combustion chemical mechanism and multi-dimensional simulation development. The improved understanding of NRP plasma reactors and the combustion characteristics of their reformate gases will set the foundation for the development and optimization of a variety of ammonia-to-power conversion systems including internal combustion engines and gas turbines, which could otherwise only progress through cumbersome empirical iteration.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.

可再生能源系统（例如，风能、水力、太阳能）将在世界电力供应中发挥主导作用，但在实现从化石燃料中独立出来之前，必须有成本效益高的方法来储存可再生能源，并将其用于难以脱碳的运输部门。氨（NH3）可以使用可再生能源合成，并且可以容易地作为液体储存/运输，作为无碳低成本化学能量储存介质和用于重型货运/海洋应用的潜在燃料已经引起了极大的兴趣。虽然氨作为一种储能解决方案和燃料受到关注是有必要的，但其低反应性和在燃烧过程中产生一氧化氮排放的倾向是大规模采用的关键障碍。通过NSF-BSF联合项目，科罗拉多州立大学和以色列理工学院的研究人员正在合作，以提高开发等离子体辅助氨重整策略所需的科学认识，从而使氨能够在最先进的燃烧设备中使用。所提出的努力的关键成果包括一个验证氨等离子体化学模型和验证燃烧模拟策略等离子体重整氨混合物在发动机相关条件。研究成果将有利于能源和交通部门-这些行业占全球温室气体排放量的73%-通过支持开发高保真模型来缩短下一代无碳能源转换设备的设计周期。来自NSF/BSF的这一独特的资助机会将有助于促进国际合作，利用Technion在等离子体重整方面的独特专业知识以及科罗拉多州立大学的燃烧和激光诊断，并将支持跨境的高影响力教育和多样性建设活动。研究结果将在出版物中分享，在会议上，并将被整合到合作机构的联合本科生和研究生课程。该研究将定期在K-12推广活动中突出显示。提案团队的初步等离子体和燃烧动力学建模表明，NRP等离子体重整混合物的可燃性和火焰速度在广泛的操作条件下可与传统燃料相媲美。等离子体反应器内的详细动力学已被检查，包括确定的关键作用的NH 2自由基减少NO燃烧排放。这项工作旨在通过实验验证来阐述这些建模结果，为未来基于系统的开发和优化工作奠定基础。工作计划的主要内容是：（1）在新构造的NRP等离子体反应器内的重整物种类测量，以验证和改进现有的NH3等离子体动力学模型，（2）通过光腔衰荡光谱（CRDS）在NRP内的NH 2测量，以阐明NH 2在等离子体动力学和NOx还原中的作用，以及（3）使用激光点火快速压缩机在相关条件下测量所得NH 3重整物混合物的点火延迟和火焰速度。这些努力将解决当前文献中的空白，包括：（1）详细研究等离子体脉冲频率、振幅和反应器压力/温度对NRP反应器中NH3和NH3/空气重整效率的相对影响，构成动力学建模努力的验证数据集;（2）首次直接测量ns脉冲系统中NH 2自由基形成，用于与动力学模型进行定量比较;以及（3）NH3/H2/O2/N2重整混合物的点火延迟和火焰速度测量扩展到当前文献中稀疏的温度/压力区域，具有痕量NO/NO2、变化的当量比和诱导的湍流，提供了支持NH3燃烧化学机理和多维模拟开发的宝贵数据集。对NRP等离子体反应器及其重整气燃烧特性的进一步了解将为开发和优化各种氨-动力转换系统（包括内燃机和燃气轮机）奠定基础。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学术价值和更广泛的影响审查标准。