Supersonic flow imaging via nanoparticles
Supersonic flow imaging via nanoparticles
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DOI：
10.1007/s11431-009-0281-3
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发表时间：
2009-12
期刊：
影响因子：
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通讯作者：
Yu-xin Zhao;S. Yi;L. Tian;Zhongyu Cheng
中科院分区：
文献类型：
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作者：
Yu-xin Zhao;S. Yi;L. Tian;Zhongyu Cheng
由于超声速流动中存在可压缩性、激波、不稳定性和湍流等因素的影响，目前的流动显示和成像技术在高时空分辨率和高信噪比测量方面遇到了一些问题。因此，纳米粒子的平面激光散射法（NPLS）的发展。该方法以纳米粒子为示踪剂，脉冲平面激光器为光源，通过CCD记录流场中粒子的图像，实现了高时空分辨率的超声速流场成像。根据多相流理论和斜激波标定实验，研究了纳米粒子在超声速流场中的流动跟随能力。利用光散射理论分析了纳米粒子的激光散射特性。理论和实验研究结果表明，纳米粒子的动力学行为和光散射特性极大地提高了NPLS的时空分辨率和信噪比，使NPLS能够以较高的时空分辨率清晰地成像激波、膨胀、马赫盘、边界层、滑移线和混合层等流场。
Due to influence of compressibility, shock wave, instabilities, and turbulence on supersonic flows, current flow visualization and imaging techniques encounter some problems in high spatiotemporal resolution and high signal-to-noise ratio (SNR) measurements. Therefore, nanoparticle based planar laser scattering method (NPLS) is developed here. The nanoparticles are used as tracer, and pulse planar laser is used as light source in NPLS; by recording images of particles in flow field with CCD, high spatiotemporal resolution supersonic flow imaging is realized. The flow-following ability of nanoparticles in supersonic flows is studied according to multiphase flow theory and calibrating experiment of oblique shock wave. The laser scattering characteristics of nanoparticles are analyzed with light scattering theory. The results of theoretical and experimental studies show that the dynamic behavior and light scattering characteristics of nanoparticles highly enhance the spatiotemporal resolution and SNR of NPLS, with which the flow field involving shock wave, expansion, Mach disk, boundary layer, sliding-line, and mixing layer can be imaged clearly at high spatiotemporal resolution.