Laser-plasma induced shock waves in micro shock tubes
Laser-plasma induced shock waves in micro shock tubes
复制标题
微型激波管中的激光等离子体诱导激波
DOI：
10.1088/1367-2630/aa83d8
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发表时间：
2017
影响因子：
3.3
通讯作者：
W. Garen
中科院分区：
文献类型：
--
作者：
U. Teubner;Y. Kai;T. Schlegel;D.E. Zeitoun;W. Garen
例如，借助激光器或激波管产生冲击波是宏观尺度上的一个常见课题。另一方面，当前较小规模的趋势变得越来越重要。特别是，直径为亚毫米或微米级的小通道或管中的冲击波在过去几年引起了人们的广泛兴趣。但是，冲击波效应的缩小，例如传播过程中的压力降低和马赫数衰减、粘性和热效应、层流和湍流，从宏观到微观甚至纳米范围不一定是直接的。尽管在这个新领域已有一些理论研究，但对实验的需求很大，但由于缺乏合适的方法，实验大多缺失。目前的工作介绍了一种产生微尺度冲击波的新方法，即激光诱导微冲击波（LIMS）。 LIMS 方法应用飞秒激光在位于微管入口处的薄铝目标中引发光学击穿。随后，高压铝等离子体发射冲击波并开始传播到管内。该专题工作首次提出了在微米级管中明确条件下直接微冲击波产生和传播的实验研究。它们针对不同的条件和直径小至 50 μm 的管进行。与之前涉及压力传感器的毫米直径范围内的冲击波研究不同，本工作采用光学方法进行非接触式测量。这些实验得到了额外模拟的支持。应用一维数值水电编码来模拟冲击波产生过程。通过求解二维纳维-斯托克斯方程来分析微管中激波的进一步传播。两种模拟都与实验结果非常吻合。
Shock wave generation with help of lasers or shock tubes, for example, is a common subject at macroscopic scale. On the other hand, the current tendency towards smaller scales becomes more and more important. In particular, shock waves in small channels or tubes with sub-mm or micron-sized diameter have attracted much interest within the last years. But downscaling of shock wave effects such as pressure decrease and Mach number attenuation during propagation, viscous and heat effects, laminar and turbulent flow is not necessarily straightforward from macro to micro or even nano range. Although several theoretical investigations are available in this new field, there is a strong demand on experiments, which are mostly missing due to the lack of suitable methods. The present work introduces a novel method for the generation of shock waves at microscale, namely laser-induced micro shock waves (LIMS). The LIMS method applies a femtosecond laser to induce an optical breakdown in a thin aluminum target located at the entrance of a micro tube. Subsequently, a shock wave is launched by the high pressure aluminum plasma and starts propagating into the tube. The topical work presents, for the first time, experimental investigations on direct micro shock wave generation and propagation at well-defined conditions in micron-sized tubes. They are performed for different conditions and tubes down to 50 μm diameter. Different from previous shock wave investigations in the mm-diameter range that involve pressure transducers, the present work applies non-contact measurements by optical methods. The experiments are supported by additional simulations. A one-dimensional numerical hydrocode is applied to simulate the shock wave generation process. Further propagation of the shock in a micro tube is analyzed by solving two-dimensional Navier–Stokes equations. Both simulations agree well with the experimental results.
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影响因子：
2.4
作者：
S. Eliezer;A. Ghatak;H. Hora;E. Teller
通讯作者：
S. Eliezer;A. Ghatak;H. Hora;E. Teller
激波管技术在冷气动态喷涂过程中应用的数值研究
影响因子：
3.1
作者：
R. Nickel;K. Bobzin;E. Lugscheider;D. Parkot;W. Varava;H. Olivier;X. Luo
通讯作者：
X. Luo
影响因子：
2.2
作者：
U. Teubner;C. Wuelker;W. Theobald;E. Förster
通讯作者：
U. Teubner;C. Wuelker;W. Theobald;E. Förster
影响因子：
2.2
作者：
Garen, W.;Hegedus, F.;Teubner, U.
通讯作者：
Teubner, U.
影响因子：
2.2
作者：
V. Fortov;I. Lomonosov
通讯作者：
V. Fortov;I. Lomonosov