Collaborative Research: Plasma Assisted Ammonia Combustion: Kinetics, Flame Stabilization and Emission

氨被认为是一种可再生燃料。然而，氨燃烧存在两个主要问题，这两个问题阻碍了其实际应用。一是氨火焰非常不稳定，很容易被扑灭。另一个问题是它的高排放，污染了环境。在这个项目中，一个合作小组将研究使用等离子体(放电)来强化氨燃烧过程，同时减少排放。等离子体-氨燃烧相互作用以前没有被研究过。该奖项将使用实验和计算工具研究潜在的物理和化学过程。从实验数据中获得的新见解将用于开发可用于与可再生能源相关的研究的计算模型。在这个项目中，本科生和研究生将接受实验和计算技能的实践培训。他们成为美国科学、技术、工程和数学(STEM)劳动力的新贡献者。明尼苏达大学和佐治亚理工学院都有很大的机会让代表不足的学生和研究人员参与进来。该项目的目标是了解通过非平衡等离子体同时稳定氨焰和减少NOx排放的物理和化学过程。该项目有两个关键假设：(1)等离子体引入的快速氨氧化/分解增强了火焰；(2)等离子体产生的NH和NH2减少了NOx的排放。因此，这项研究的范围和目标是：(1)研究氨等离子体的基本化学动力学，以了解不同还原电场(E/N)下的等离子体对氨等离子体的即时解离和氧化作用。这将通过在流动反应器中进行实验和一维(1D)数值模拟来实现，其中包括详细的等离子体和燃烧化学动力学的测量和一维(1D)数值模拟；(Ii)通过在模型燃气轮机燃烧室中使用NH、NH2、NO和OH平面激光诱导荧光(PLIF)和由详细的1D建模导出的简化等离子体模型进行三维(3D)直接数值模拟(DNS)来研究等离子体动力学和火焰动力学(包括稀薄喷吹和热声燃烧不稳定性)之间的相互作用。实验工作将由佐治亚理工学院团队进行，数值工作将由明尼苏达大学团队进行。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。

Ammonia is considered as a renewable fuel. However, ammonia combustion suffers from two major issues which are preventing its practical application. One is that ammonia flame is very unstable and can easily get extinguished. The other issue is its high emission, which pollutes the environment. In this project, a collaborative team will investigate using plasma (electric discharge) to enhance ammonia combustion process and reduce emission at the same time. The plasma-ammonia combustion interaction has not been studied previously. This award will investigate the underlying physical and chemical processes using experimental and computational tools. The new insights gained from experimental data will be used to develop computational models that can be used in research related to renewable energy. In this project, undergraduate and graduate students will receive hands-on training in experimental and computational skills. They become new contributors to the science, technology, engineering, and mathematics (STEM) workforce of United States. Significant opportunities exist at both University of Minnesota and Georgia Institute of Technology to engage underrepresented students and researchers.The goal of this project is to understand the physical and chemical processes to stabilize ammonia flames and reduce NOx emission simultaneously by non-equilibrium plasma. This project has two key hypotheses: (1) prompt ammonia oxidation/decomposition introduced by plasma enhances flame; (2) the production of NH and NH2 from plasma reduces NOx emission. Accordingly, the scope and objectives of this proposed research are: (i) investigation of fundamental ammonia plasma chemical kinetics to understand its prompt dissociation and oxidation induced by plasma at different values of reduced electric field (E/N). This will be achieved by conducting experiments in a flow reactor with speciation measurement and one-dimensional (1D) numerical simulations with detailed plasma and combustion chemical kinetics; (ii) investigation of interactions between plasma kinetics and flame dynamics (including lean blow-off and thermoacoustic combustion instability) by conducting experiments in a model gas turbine combustor using NH, NH2, NO and OH planar laser induced fluorescence (PLIF) and three-dimensional (3D) direct numerical simulations (DNS) with a simplified plasma model deduced from detailed 1D modeling. The experimental work will be conducted by the Georgia Institute of Technology team and the numerical work will be conducted by the University of Minnesota team.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.