Flow visualization of supersonic laminar flow over a backward-facing step via NPLS
Flow visualization of supersonic laminar flow over a backward-facing step via NPLS
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通过 NPLS 对向后台阶上的超音速层流进行流动可视化
DOI：
10.1007/s00193-012-0378-7
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发表时间：
2013-07
期刊：
影响因子：
2.2
通讯作者：
Zhu, Y. Z.
中科院分区：
文献类型：
--
作者：
Yi, S. H.;Tian, L. F.;He, L.;Zhu, Y. Z.
在低噪声进气道风洞中进行了5 mm高后台阶超音速层流的实验研究。为了研究ma = 3.0和3.8的后向台阶层流的精细结构，采用纳米示踪平面激光散射技术对层流进行了显示。在瞬态流场中，揭示了超声速层流边界层、分离、再附着、再发展的湍流边界层、膨胀波扇和再附着激波等流动结构。在theMa= 3.0 BFS（后向阶跃）流动中，通过对四个典型区域的测量可以发现，弱激波的出现与自由剪切层中出现的K-H （Kelvin-Helmholtz）涡有关，并且这些波收敛为再附激波的过程明显。通过大量的测量，可以得到时均流场的结构。再附着发生在台阶下游的位置，大约7-7.5小时的距离。重新附着后，恢复边界层迅速发展为湍流，厚度以4.6°的角度增加。在x = 14h位置，重新发展的边界层厚度约为原始厚度的10倍，但仍未转变为充分发展的湍流。而在theMa= 3.8的流动中，由于膨胀减小，弱激波很少出现。根据平均结果，认为再附着点在x = 15h附近。重新附着的冲击不清晰，这意味着膨胀和压缩效应不强烈。
An experimental study on a supersonic laminar flow over a backward-facing step of 5 mm height was undertaken in a low-noise indraft wind tunnel. To investigate the fine structures ofMa= 3.0 and 3.8 laminar flow over a backward-facing step, nanotracer planar laser scattering was adopted for flow visualization. Flow structures, including supersonic laminar boundary layer, separation, reattachment, redeveloping turbulent boundary layer, expansion wave fan and reattachment shock, were revealed in the transient flow fields. In theMa= 3.0 BFS (backward-facing step) flow, by measuring four typical regions, it could be found that the emergence of weak shock waves was related to the K–H (Kelvin–Helmholtz) vortex which appeared in the free shear layer and that the convergence of these waves into a reattachment shock was distinct. Based on large numbers of measurements, the structure of time-averaging flow field could be gained. Reattachment occurred at the location downstream from the step, about 7–7.5 h distance. After reattachment, the recovery boundary layer developed into turbulence quickly and its thickness increased at an angle of 4.6°. At the location ofX= 14h, the redeveloping boundary layer was about ten times thicker than its original thickness, but it still had not changed into fully developed turbulence. However, in theMa= 3.8 flow, the emergence of weak shock waves could be seen seldom, due to the decrease of expansion. The reattachment point was thought to be nearX= 15haccording to the averaging result. The reattachment shock was not legible, which meant the expansion and compression effects were not intensive.
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DOI：
10.1007/s11433-009-0180-4
发表时间：
2009-08
期刊：
Science in China Series G: Physics, Mechanics and Astronomy
影响因子：
--
作者：
L. Tian;S. Yi;Yu-xin Zhao;Lin He;Zhongyu Cheng
通讯作者：
L. Tian;S. Yi;Yu-xin Zhao;Lin He;Zhongyu Cheng
影响因子：
2.4
作者：
G. Shen;G. Ma
通讯作者：
G. Shen;G. Ma
DOI：
10.2514/6.1998-939
发表时间：
1998-01
期刊：
--
影响因子：
--
作者：
A. Matsuo;M. Mizomoto
通讯作者：
A. Matsuo;M. Mizomoto
DOI：
10.1007/s11431-009-0281-3
发表时间：
2009-12
期刊：
Science in China Series E: Technological Sciences
影响因子：
--
作者：
Yu-xin Zhao;S. Yi;L. Tian;Zhongyu Cheng
通讯作者：
Yu-xin Zhao;S. Yi;L. Tian;Zhongyu Cheng
基于NPLS的超声速混合层流动控制研究
DOI：
10.1007/s11433-009-0301-0
发表时间：
2009-12
期刊：
Science in China - Series G: Physics Mechanics and Astronomy
影响因子：
--
作者：
He Lin;Zhao YuXin;Tian LiFeng;Cheng ZhongYu
通讯作者：
Cheng ZhongYu