EAGER: High-Speed Imaging Studies of Fuel-Spray Physics for Low-Temperature and Low-Density Ambient Conditions

越来越多的发动机和发电系统采用基于喷雾的方法将燃料引入燃烧室。喷雾和喷雾燃烧涉及物理过程（例如，燃料汽化，燃料-空气混合）和化学过程（例如，点火、污染物形成），这两者都没有被完全理解。此外，汽化和混合设定了燃烧的初始条件，因此直接影响燃烧效率和排放。这项研究的目的是调查的物理过程中涉及的燃料喷雾，特别是在燃料喷射到相对低温和低密度的环境条件。这些条件是先进的发动机燃烧策略的特征，例如早期直接喷射，其越来越多地用于提高效率和降低不必要的排放。研究将在一个喷雾室中进行，该喷雾室设计有广泛的光学通道，在实验期间，惰性气体将连续流过该喷雾室，以便在没有燃烧复杂影响的情况下对喷雾物理学进行基础研究。研究将集中在燃料喷雾的液相和气相的渗透、分散和湍流。这些数据将使用新的高速成像技术，将作为该项目的一部分开发。研究人员将尝试开发一种技术，同时使用一个高速摄像机获得液相和气相信息。实验结果可能会导致开发出更好的和更灵活的模型，这些模型可能会挑战关于燃料喷雾的传统智慧，该项目将通过为代表性不足的学生的研究活动和研究生教育提供支持，对代表性不足的群体的参与产生直接和切实的影响。此外，该项目将有利于本科教育的机械工程系在亚拉巴马大学，作为调查员将纳入现有的课程在内燃机的讲座和实验室部分的主题和研究结果。更广泛地说，这项工作将有助于改进预测性喷雾和燃烧模型，这反过来将有助于开发更清洁、更高效的燃烧装置。因此，这项研究有可能影响这个国家的能源安全和能源独立。

Increasingly, engines and power-generation systems are employing spray-based methods to introduce fuel into the combustion chamber. Sprays and spray combustion involve both physical processes (e.g., fuel vaporization, fuel-air mixing) and chemical processes (e.g., ignition, pollutant formation), neither of which are fully understood. In addition, vaporization and mixing set the initial conditions for combustion, and thus directly influence combustion efficiency and emissions. The purpose of this research is to investigate the physical processes involved in fuel sprays, particularly for conditions where fuel is sprayed into relatively low-temperature and low-density surroundings. Such conditions are characteristic of advanced engine combustion strategies, such as early direct-injection, which are increasingly being used to enhance efficiency and lower unwanted emissions. Research will be conducted in a spray chamber designed with extensive optical access, and through which an inert gas will flow continuously during experiments to allow fundamental studies of spray physics in the absence of the complicating effects of combustion. Studies will focus on penetration, dispersion, and turbulence of both the liquid and vapor phases of fuel sprays. These data will be sought using novel high-speed imaging techniques that will be developed as part of this project. The investigator will attempt to develop a technique to obtain both liquid- and vapor-phase information simultaneously using a single high-speed camera. Experimental results could lead to development of improved and more-flexible models that are likely to challenge conventional wisdom about fuel sprays.This project will have a direct and tangible effect on participation from underrepresented groups by providing support for the research activities and graduate education of an underrepresented student. In addition, the project will benefit undergraduate education in the Mechanical Engineering Department at The University of Alabama, as the investigator will incorporate the subject matter and results of the research into both the lecture and laboratory portions of an existing course in combustion engines. More broadly, the work will contribute to improvement of predictive spray and combustion models, which in turn will contribute to the development of cleaner and more-efficient combustion devices. This research, therefore, has the potential to impact the energy security and energy independence of this nation.