High-Pressure Combustion of Transient Dense Sprays: An Experimental, Theoretical, and Numerical Investigation of the Relationship between Spray Physics and NOx Emissions

本文研究了柴油机喷油量作为控制参数与排放的关系。 具体而言，该研究解决了一氧化氮的形成和高压密集喷雾燃烧动力学，脉冲喷射和喷雾瞬变之间的关系。 实验工具包括一个定制的柴油发动机模拟器，能够产生类似的条件下，在柴油喷射前，红外散射测量，以量化燃料液滴的大小和液体的体积分数在密集的喷雾区域，和线拉曼测量，以量化燃料/空气比和温度。 通过傅里叶变换红外光谱法进行的燃烧后气体分析允许测量作为操作参数和喷射燃料的函数的一氧化氮。 建模包括微尺度（单个液滴）、中尺度（多个液滴）和宏观尺度系统。 模型用于预测发动机中作为喷射参数的函数的排放趋势。 为了使物理系统和数值系统尽可能接近一致，建模和实验工作之间的持续互动是必要的。

This is a study of the relationship between fuel injection as a controlling parameter and emissions from diesel engines. Specifically, the study addresses the relationships between formation of nitric oxide and high-pressure dense-spray combustion dynamics, pulsed injections and spray transients. Experimental tools include a custom-built diesel engine simulator capable of producing conditions similar to those in a diesel immediately prior to injection, infrared scattering measurements to quantify fuel droplet size and liquid volume fraction in the dense-spray region, and line Raman measurements to quantify fuel/air ratio and temperature. Post-combustion gas analysis by Fourier transform infrared spectroscopy allows measurement of nitric oxide as functions of operating parameters and fuel injected. Modeling includes microscale (single droplet), mesoscale (multiple droplet), and macroscale systems. Models are used to predict emission trends in engines as a function of injection parameters. Continuous interaction between the modeling and experimental efforts are necessary to make the physical and numerical systems as nearly identical as possible.