Characterization of organic tracers for laser-based quantitative diagnostics of fuel concentration, temperature, and equivalence ratio in practical combustion processes

汽油直喷和均质压缩点火（HCCI）等内燃机的创新概念需要在点火前详细了解气体混合物。这包括燃料和空气浓度以及温度。利用示踪剂和荧光燃料化合物进行基于激光诱导荧光（LIF）的燃料可视化在过去二十年中已经发展成为一种重要的工程工具。然而，根据燃料-空气比或温度来准确解释荧光信号需要对化合物的光物理行为有良好的基础知识。在一项国际合作中，我们最近表明，对于同时升高压力和温度的重要条件（即内燃机），特别缺乏有关这些特性的信息。因此，我们建议改进定量、多维示踪- lif测量的基础，为当前发动机研究所需的全谱应用提供技术。该项目的目标是(a)扩展对选定有机化合物的光谱知识(b)改进用于信号解释的光物理模型(c)研究示踪剂的稳定性极限(d)演示光学可及发动机缸体中的测量结果。该提案包括继续与斯坦福大学和密歇根大学安娜堡分校的合作。

Innovative concepts for internal combustion engines like gasoline direct injection and homogeneous charge compression ignition (HCCI) require a detailed knowledge about the gas mixture prior to ignition. This includes fuel and air concentration as well as temperature. The use of tracers and fluorescing fuel compounds for fuel visualization based on laser-induced fluorescence (LIF) has grown to an important engineering tool over the last two decades. However, accurate interpretation of fluorescence signals in terms of fuel-air ratio or temperature requires sound fundamental knowledge of the com-pounds photo-physical behavior. In an international collaboration we have recently shown that there is a particular lack of information about these properties for important conditions of simultaneous elevated pressure and temperature (i.e. in internal combustion engines). We therefore propose to improve the fundamental basis for quantitative, multi-dimensional tracer-LIF measurements to provide techniques for the full spectrum of applications demanded by current engine research. The objectives of this project are to (a) expand the spectroscopic knowledge on selected organic compounds (b) improve the photo-physical models for signal interpretation (c) study the stability limits of the tracers and (d) demonstrate the measurements in the cylinder of an optically accessible engine. This proposal includes continuation of the collaboration with Stanford Univ. and Univ. of Michigan in Ann Arbor.