Static and dynamic characterization of a focused laser differential interferometer
Static and dynamic characterization of a focused laser differential interferometer
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聚焦激光差分干涉仪的静态和动态表征
DOI：
10.1007/s00348-020-03013-6
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发表时间：
2020
影响因子：
2.4
通讯作者：
J. Austin
中科院分区：
文献类型：
--
作者：
J. M. Lawson;M. Neet;I. J. Grossman;J. Austin
通过静态和动态台架测试，对聚焦激光差分干涉仪（FLDI）进行了实验表征。静态响应探测使用一个稳定的，层流氦射流，和动态响应进行了研究，使用超声波声束。在射流的情况下，使用马赫-曾德尔干涉仪与FLDI同时集成操作独立测量折射率场。静态响应的实验数据进行了比较与数值模拟的FLDI的基础上几何光学和光线跟踪算法，而动态响应进行了比较，从同一理论的解析传递函数。实验和理论之间发现密切的定量协议，验证这种方法来建模FLDI性能。重点是量化的空间灵敏度的系统，这是一个关键特性的FLDI，特别是当应用于超高速地面试验设施，湍流存在于剪切层或边界层外的核心流。
A focused laser differential interferometer (FLDI) is experimentally characterized via static and dynamic benchtop testing. The static response is probed using a steady, laminar helium jet, and the dynamic response is investigated using an ultrasonic acoustic beam. In the case of the jet, the refractive index field is independently measured using a Mach-Zehnder interferometer operating simultaneously integrated with FLDI. The experimental data for the static response are compared with numerical simulations of the FLDI based on geometric optics and a ray-tracing algorithm, while the dynamic response is compared with an analytical transfer function derived from the same theory. Close quantitative agreement is found between experiment and theory, validating this approach to modeling FLDI performance. Emphasis is given to quantification of the spatial sensitivity of the system which is a key characteristic of FLDI, especially when applied to hypervelocity ground testing facilities where turbulent flow exists in shear or boundary layers outside the core flow.