反应活性可控氛围下预混压燃发动机颗粒物微观理化特性及其形成机理的研究

反应活性可控压缩燃烧技术是一种可实现发动机高效清洁燃烧的有效措施，可显著降低发动机的颗粒物排放，但是我们还不完全清楚这种燃烧模式下颗粒物的形成机理、粒径分布特性以及颗粒微观特性和氧化活性之间的相互影响关系。为此，本申请拟将化学反应动力学数值模拟计算，热重分析和谱分析等先进测试方法以及发动机排放特性试验等技术手段相结合来研究预混燃料活性、比例、温度等边界参数对颗粒物粒径分布、生长历程、微观结构、表面官能团和氧化活性的影响规律，进而探讨颗粒物微观结构、物理化学特性和氧化活性之间的相互影响关系，最终获得反应活性可控条件下颗粒物前驱体单/多环芳香烃的形成路径、颗粒物微观理化特性对氧化活性的影响机理，从而深刻揭示反应活性可控压缩燃烧方式降低发动机颗粒物的作用机制。本申请所获得的研究结果将为合理组织柴油机燃烧过程、制定颗粒排放物有效控制策略以及科学设计柴油机后处理器提供基础理论依据。

Reactivity charge compression ignition combustion technology is one kind of new combustion modes to realize high-efficiency and low emission combustion, and PM emission can be reduced obviously by this combustion mode. However, the PM formation mechanism, particulate size distribution and the mutual influences between the particulate micro-properties and oxidation reactivity during this combustion mode have not yet been fully verified. For this purpose, the effects of the boundary parameters such as premixed fuel reactivity, proportion and temperatureon the particulate size distribution, the particulate formation process, nanostructure, surface functional group and oxidation reactivity are determined by the numerical simulation of chemical reaction kinetics, advanced test method based on thermogravimetric analysis and multi-spectral analysis as well as the engine test. Furthermore, the mutual influences among particulate nanostructure, particulate physical and chemical properties and oxidation reactivity are discussed. It is finally obtained that the formation path of the particle precursors-single/polycyclic aromatic hydrocarbon, particulate physical and chemical properties and particulate oxidation reactivity under the condition of the reactivity charge compression ignition combustion. Thus, the PM reducing mechanisms in the combustion process of the reactivity charge compression ignition are revealed. The results can provide theoretical fundamentals for organizing the combustion process of diesel engine effectively, formulating the effective control strategies of PM emissions and designing the diesel after-treatment scientifically.