Acquisition of a High-Pulse-Energy, Narrow-Linewidth, UV Laser Source: Improved Quantitative Gas-Phase Mixing Measurements in Turbulent Spray Flows

1336913sutton该项目涉及采购组件，以组装超高脉冲能量（300mj /脉冲，254 nm），可调谐，窄线宽（~ 30 MHz）紫外激光系统。该仪器将成为紫外线过滤瑞利散射（FRS）测量系统的主要组成部分，用于研究湍流喷雾流中的汽化和气相混合过程。随后使用新的紫外激光和FRS系统的实验将针对烃类火焰的气相测温，这将产生有关烟尘传输和反应化学的新信息。也许最著名的湍流喷雾存在于能量转换系统中，其中液体燃料进入氧化环境，蒸发，并在反应前与氧化剂混合。在多相喷雾环境中，气相混合一直没有得到广泛的研究，这主要是由于液相的共存使得气相浓度的独立测量非常困难。PI将使用新的高能紫外激光器（254 nm）与原子汞过滤器结合使用，在液相液滴干扰最小的情况下进行定量气相测量的紫外FRS测量。大多数工程系统使用由多个阶段组成的工作介质，这一事实解决了项目更广泛的影响。特别是，喷雾流在许多应用中具有重要意义，包括汽车发动机，液体推进剂火箭发动机，工业炉和燃气轮机。随着对汽化和气相混合过程的更好理解，改进喷油器和燃烧器的设计将成为可能，从而改善对点火的控制，提高效率，提高稳定性，减少污染物排放。在与研究相关的教育方面，拟议的激光系统将被博士后研究人员和本科生/研究生使用，以加强他们在最新测量技术方面的培训。我们的技术未来取决于开发新的方法和能够解决这些复杂问题的新劳动力。

1336913SuttonThis project involves the acquisition of components to assemble an ultra-high-pulse-energy (300 mJ/pulse at 254 nm), tunable, narrow-linewidth (~ 30 MHz) UV laser system. This instrument will be the primary component used within a UV filtered Rayleigh scattering (FRS) measurement system to investigate vaporization and gas-phase mixing processes within turbulent spray flows. Subsequent experiments using the new UV laser and FRS system will target gas-phase thermometry in sooting hydrocarbon flames which will yield new information concerning soot transport and reaction chemistry. Perhaps the best known examples of turbulent sprays exist in energy conversion systems in which a liquid fuel issues into an oxidizing environment, evaporates, and mixes with the oxidizer before reacting. Gas-phase mixing has not been studied extensively in multi-phase spray environments primarily due the co-existence of the liquid phase that makes the independent measurement of the vapor-phase concentration very difficult. The PI will use the new high-energy UV laser (254 nm) in conjunction with an atomic mercury filter to perform UV FRS measurements for quantitative gas-phase measurements with minimal interference from the liquid-phase droplets. Broader impacts of the project are addressed by the fact that the majority of engineering systems operate with working mediums that consist of multiple phases. In particular, spray flows are of significant interest in many applications including automotive engines, liquid-propellant rocket engines, industrial furnaces, and gas-turbines. With a better understanding of the vaporization and gas-phase mixing processes, improvements in fuel injector and combustor design will be possible, resulting in an improved control over ignition and a potential for increased efficiency, increased stability, and decreased pollutant emissions. In terms of research-related education, the proposed laser system will be used by post-doctoral researchers and undergraduate/graduate students to enhance their training in state-of-the art measurement techniques. Our technological future depends on developing both new methodologies and a new workforce capable of tackling such complicated problems.