Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, Texas 78712, USA.
Opt Lett. 2011 Nov 1;36(21):4185-7. doi: 10.1364/OL.36.004185.
Experiments were performed to explore the use of two-photon planar laser-induced fluorescence (PLIF) of krypton gas for applications of scalar imaging in supersonic flows. Experiments were performed in an underexpanded jet of krypton, which exhibited a wide range of conditions, from subsonic to hypersonic. Excellent signal-to-noise ratios were obtained, showing the technique is suitable for single-shot imaging. The data were used to infer the distribution of gas density and temperature by correcting the fluorescence signal for quenching effects and using isentropic relations. The centerline variation of the density and temperature from the experiments agree very well with those predicted with an empirical correlation and a CFD simulation (FLUENT). Overall, the high signal levels and quantifiable measurements indicate that Kr-PLIF could be an effective scalar marker for use in supersonic and hypersonic flow applications.
实验旨在探索使用双光子平面激光诱导荧光（PLIF）的氪气进行超声速流场标量成像的应用。实验在氪的欠膨胀射流中进行，该射流呈现出从亚声速到高超声速的广泛条件。获得了优异的信噪比，表明该技术适合单次成像。通过校正荧光信号的猝灭效应并使用等熵关系，数据被用于推断气体密度和温度的分布。实验得出的密度和温度中心线变化与经验相关性和 CFD 模拟（FLUENT）预测的非常吻合。总的来说，高信号水平和可量化的测量表明 Kr-PLIF 可以成为超声速和高超声速流动应用中有效的标量标记物。
