Multi-Component Reactive Pressure-dependent Chemistry Verified by Multi-Scale Uncertainty Quantification

新兴的内燃机技术显示出提高燃油经济性和减少环境污染的前景。然而，工程师们面临着设计挑战，因为这些改进的发动机需要空前精确的燃料燃烧化学控制。优化设计现在要求对燃烧化学的科学描述达到前所未有的精确。对于使用计算机模型的工程师来说尤其如此。为了满足这些需求，该项目的目标是创建和验证预测燃烧化学模型。这个项目将在分子水平上创建燃烧化学的描述，然后根据燃烧测量验证这些描述。这项研究中描述的基本化学行为也将有助于更好地理解行星大气。最后，该项目将在课堂上为学生带来研究发现，培训研究生进行最先进的计算机建模，并在学校参观和实验室参观中与当地K-12学生分享科学思维过程。拟议研究的技术目标是创建一个符合第一原理和燃烧实验的多尺度、不确定量化的H2/CO/CH2O燃烧模型。一个主要的焦点是建立高反应性发动机环境的唯象反应类型和速率定律，特别是对于对温度、压力和混合物组成具有复杂依赖关系的非热动力学序列。PI建议1)对重要的非热动力学序列进行最先进的第一性原理计算；2)构建一个多尺度燃烧模型，直接连接分子行为(从第一性原理计算)到宏观行为(在燃烧实验中可测量)；以及3)测试模型与第一性原理和燃烧实验的一致性，通过逆不确定度量化来验证模型。到项目结束时，所建立的反应类型和速率定律将作为燃烧和大气中其他反应的原型，所产生的高精度模型将准备好用于其他科学和工程应用。

Emerging combustion engine technologies show promise for improved fuel economy and reduced environmental pollution. However, engineers face design challenges because these improved engines require unprecedentedly precise control of fuel combustion chemistry. Optimal design now requires scientific descriptions of combustion chemistry to be unprecedentedly precise. This is especially true for engineers using computer models. To serve these needs, the project goal is to create and validate predictive combustion chemistry models. This project will create descriptions of combustion chemistry at the molecular level and then validate these descriptions against combustion measurements. The fundamental chemical behavior characterized in this research will also lead to a greater understanding of planetary atmospheres. Finally, this project will bring research discoveries to students in the classroom, train graduate students in state-of-the-art computer modeling, and share the scientific thought process with local K-12 students in school visits and lab tours.The technical objective of the proposed research is to create a multi-scale, uncertainty-quantified model of H2/CO/CH2O combustion that is consistent with both first principles and combustion experiments. A primary focus is establishing the types of phenomenological reactions and rate laws of highly reactive engine environments, especially for non-thermal kinetic sequences that have complex dependences on temperature, pressure, and mixture composition. The PI proposes to 1) perform state-of-the-art first principles calculations for important non-thermal kinetic sequences; 2) construct a multi-scale combustion model that directly bridges molecular behavior, calculable from first principles, to macroscopic behavior, measurable in combustion experiments; and 3) test model consistency with both first principles and combustion experiments to validate the model via inverse uncertainty quantification. By the project end, the established reaction types and rate laws will serve as prototypes for other reactions in combustion and atmospheres, and the produced high-accuracy model will be ready to use in other scientific and engineering applications.