CAREER: Disruption and Vaporization of Superheated Droplets in Compressible Flow

摘要- CTS-9733830 Hermanson，James C. 高速气流中液滴的破碎和汽化发生在两相流、喷雾干燥、火箭喷嘴流、液体燃料喷射和蒸汽涡轮机叶片侵蚀中。 如果实现高水平的分散和快速混合，在许多应用中可以实现相当大的实际优势。 一种技术是闪蒸，其涉及过热液体的剧烈破坏和蒸发。 大多数现有的文献都集中在不可压缩流，并不适用于可压缩流，这是在超音速燃烧室。 过热液滴破裂、汽化和燃料/空气混合的物理学还没有很好地建立起来。 拟议的研究计划是一个全面的，实验研究的基础物理过热液体燃料的破坏和蒸发在超音速流，其中的液滴的整个体积被带到一个高水平的蒸发，以促进闪蒸。 这项工作将是第一步实现的过热液体燃料喷雾在可压缩流中的行为的基本理解，特别注意不同的不稳定性机制，影响液滴的历史。 液滴将被注入到超音速流和他们的加速和随后的蒸发将主要由平面激光诱导荧光和激光火花纹影/阴影检查。

Abstract - CTS-9733830 Hermanson, James C. The breakup and vaporization of liquid droplets in a high-speed gas stream occurs in two-phase flows, spray drying, rocket nozzle flow, liquid fuel injection, and steam turbine blade erosion. Considerable practical advantages in many applications could be realized if high levels of dispersion and rapid mixing were achieved. One technique is that of flash vaporization which involves violent disruption and vaporization of superheated liquids. Most of the extant literature is focussed on incompressible flows and is not applicable to compressible flows, which are found in supersonic combustors. The physics of superheated liquid droplet disruption, vaporization, and fuel/air mixing are not well established. The proposed research program is a comprehensive, experimental investigation of the fundamental physics of superheated liquid fuel disruption and vaporization in supersonic flow, where the entire volume of the droplet is brought to a high level of superheat to promote flash vaporization. This work will be a first step towards achieving a fundamental understanding of the behavior of superheated liquid fuel sprays in compressible flow, with particular attention paid t the different instability mechanism which affect the droplet history. Droplets will be injected into a supersonic stream and their acceleration and subsequent vaporization will be examined primarily by planar laser-induced fluorescence and laser-spark schlieren/shadowgraphs.