CAREER: Progression from soot to nanocrystalline carbon in elevated temperature flames

职业生涯：高温火焰中从烟灰到纳米晶碳的进展

基本信息

批准号：
2143979
负责人：
Joaquin Camacho
金额：
$ 56.2万
依托单位：
San Diego State University Foundation
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2022
资助国家：
美国
起止时间：
2022-03-01 至 2027-02-28
项目状态：
未结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2143979&HistoricalAwards=false
关键词：
CAREER Progression soot nanocrystalline carbon

项目摘要

Soot formation remains a crucial factor in combustion performance, public health and the environment. There is a rising need to characterize soot formation in extremely hot flames due to prominence of kerosene-fueled rockets, oxy-fuel combustion systems and other emerging combustion processes. The scientific objective is to shed light on soot formation in flames hotter than traditionally studied. A complementary experimental and computational modeling approach will be used to isolate fundamental phenomena unique to this soot formation regime. Imminent space cargo and tourism enterprises require soot models for rocket thruster design and particulate emissions predictions. Nanocrystalline carbon forms during rocket flight powered by kerosene and other hydrocarbon propellants. A more thorough consideration of performance and unknown environmental impacts (i.e. public health, climate, etc.) is facilitated by studying soot formation at elevated temperature. High temperature oxyfuel combustion, preheated air systems and enriched air processing are also examples of emerging combustion technologies operating hotter than conventional combustion. In terms of societal impact, the urgent need for more inclusive participation in graduate school and academic careers will be enhanced through collaboration with the McNair program and Bridges Community College program. Virtual teaching modules for thermofluids theory and applications will also be developed to increase participation of local high-school students.Quantification of competing soot formation processes remains a challenge. Fuel-rich flame chemistry models leading to gas-phase soot precursors vary widely for conventional combustion temperatures and no studies for elevated temperature flames exist. The same can be said for the underlying aerosol dynamics and evolution in soot nanostructure. The central hypothesis is that quantification of reversible soot precursor reactions, reduction in collision efficiency, extreme particle graphitization and, perhaps, ionization processes are required to accurately capture soot behavior at elevated temperatures. At the conclusion of the proposed activities the PI will have: (i) systematically measured individual PAH profiles and soot particle size distributions in well-characterized laminar and turbulent laboratory flames; (ii) characterized evolution in carbon nanostructure and morphology for particles formed in elevated temperature flames; (iii) assessed the role of ionization processes on soot formation in this regime; (iv) incorporated new experimental observations into new models for higher temperature soot formation; (v) demonstrated unique higher-temperature processes governing the transition from soot to newly discovered nanocrystalline carbon structure. The proposed project is significant because self-consistent development of soot formation theory will be facilitated by the comprehensive experimental and modeling approach for the benefit of conventional and higher-temperature regimes.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.

烟灰的形成仍然是燃烧性能，公共卫生和环境的关键因素。由于煤油燃料火箭，氧气燃料燃烧系统和其他新兴燃烧过程的突出，需要在极热火焰中表征烟灰的形成。科学的目标是阐明比传统研究更热的火焰中的烟灰形成。一种互补的实验和计算建模方法将用于隔离这种烟灰形成方案所特有的基本现象。迫在眉睫的太空货物和旅游企业需要火箭推进器设计和颗粒排放预测的烟灰模型。在火箭飞行过程中，由煤油和其他烃推进剂提供动力的火箭飞行过程中的纳米晶形成碳。通过在温度升高的情况下研究烟灰的形成，可以促进对性能和未知环境影响（即公共卫生，气候等）的更透彻的考虑（即公共卫生，气候等）。高温氧气燃烧，预热的空气系统和富集的空气加工也是新兴燃烧技术比传统燃烧更热的示例。在社会影响方面，将通过与McNair计划和Bridges社区学院计划的合作来增强对研究生和学术职业的迫切需求。热流体理论和应用的虚拟教学模块也将开发出来，以增加当地高中生的参与。导致气相烟灰前体的燃料富含火焰化学模型在常规燃烧温度方面差异很大，没有针对温度升高的研究。对于烟灰纳米结构中的基础气溶胶动力学和进化，也可以这样说。中心假设是对可逆的烟灰前体反应的量化，碰撞效率的降低，极端粒子石墨化以及可能需要电离过程来准确捕获高温下的烟灰行为。在提出的活动的结束时，PI将具有：（i）在特征良好的层流和湍流实验室火焰中系统测量的单个PAH轮廓和烟灰粒径分布；（ii）在温度升高中形成的颗粒的碳纳米结构和形态的进化表征；（iii）评估了电离过程在该制度中烟灰形成的作用；（iv）将新的实验观察结果纳入了更高温度烟灰形成的新模型；（v）展示了从烟灰到新发现的纳米晶体结构的过渡的独特高温过程。拟议的项目之所以重要，是因为烟灰形成理论的自以承程序的发展将通过全面的实验和建模方法来促进传统和高温方案的益处。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力和更广泛影响的评估来通过评估来支持的，这是值得的。