Accurate Determination of Branching Fractions in Ammonia Combustion

氨燃烧中支化分数的准确测定

• 批准号: 2329341
• 负责人: Claude Goldsmith
• 金额: $ 35.34万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-09-01 至 2027-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2329341&HistoricalAwards=false
• 关键词: Accurate; Determination; Branching; Fractions; Ammonia

Ammonia is a potential bridge fuel for carbon-neutral combustion. However, the combustion of ammonia can lead to various nitrogen oxides (NOx), which are major pollutants, and which can exacerbate climate change. To mitigate the impact of NOx on human health and the environment, government regulations increasingly require reduced emissions of nitrogen oxides from combustion sources. The ability to make accurate predictions of NOx formation levels will benefit engineers and scientists who need to quantify the impact of a new fuel or a new engine design on NOx emissions. These NOx submechanisms also will benefit the broader atmospheric science community, both at the local level (e.g. smog) and at the global level (e.g. climate change). The goal of this project is to measure the branching fractions for several reactions that are important in the kinetics of ammonia combustion, particularly those related to various nitrogen oxides. The investigators hypothesize that by measuring the transient concentration of two or more species simultaneously, the uncertainty in the branching fractions can be reduced relative to the current state of the art in NOx literature. To test this hypothesis, the investigators will use tunable diode laser absorption spectroscopy (TDLAS) to measure the transient concentration of NO, NO2, N2O, H2O, and/or temperature behind the reflected shock in a shock tube. These profiles will serve as validation targets for a kinetic model.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.

氨是碳中性燃烧的潜在桥梁燃料。然而，氨的燃烧会导致主要污染物的各种氮氧化物（NOX），并且会加剧气候变化。为了减轻NOX对人类健康和环境的影响，政府法规越来越多地要求减少燃烧来源的氮氧化物排放。对NOX形成水平进行准确预测的能力将使需要量化新燃料或新发动机设计对NOX排放的影响的工程师和科学家有益。这些NOX亚机构在地方一级（例如烟雾）和全球层面（例如气候变化）也将使更广泛的大气科学界受益。该项目的目的是测量几种在氨燃烧动力学中很重要的反应的分支部分，尤其是与各种氮氧化物相关的反应。研究人员假设，通过同时测量两个或多种物种的瞬态浓度，相对于NOX文献中最新的ART状态，分支部分的不确定性可以减少。为了检验这一假设，研究人员将使用可调二极管激光吸收光谱（TDLA）来测量NO，NO2，N2O，H2O和/或温度的瞬态浓度，并在冲击管中反射的冲击后面。这些概况将作为动力学模型的验证目标。该奖项反映了NSF的法定任务，并认为使用基金会的知识分子优点和更广泛的影响审查标准，被认为值得通过评估。