An experimental study on fine structures of supersonic laminar/turbulent flow over a backward-facing step based on NPLS
An experimental study on fine structures of supersonic laminar/turbulent flow over a backward-facing step based on NPLS
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基于NPLS的向后台阶超音速层流/湍流精细结构实验研究
DOI：
10.1007/s11434-011-4888-y
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发表时间：
2012-01
影响因子：
--
通讯作者：
Zhu YangZhu
中科院分区：
文献类型：
--
作者：
Yi ShiHe;He Lin;Tian LiFeng;Zhu YangZhu
在aMa=3.0低噪声进气道风洞中，对5 mm高后台阶（BFS）上的膨胀波扇、再附着激波、超声速边界层等细部结构进行了测量。通过改变台阶上游壁面表面粗糙度，可以形成超声速层流和超声速湍流。利用纳米平面激光散射技术对四个典型区域的整体流场和精细结构进行了时空特征测量。通过对瞬态流场整体结构的测量，揭示了膨胀波扇、再附着激波、超声速边界层及其分离、再附着和再开发等流动结构。对比两种时间平均流场，可以看出超声速紊流（STF-BFS）的膨胀角更大，再循环区域更短，其重新发展的边界层以较小的倾角增加，而超声速层流（SLF-BFS）的再附着激波角相同。在时间演化特征上，在SLF-BFS中，k - hvortices受剪切、膨胀、再附着和三维效应的影响，而在STF-BFS大尺度结构中，k - hvortices受膨胀、黏度和反压作用导致的再附着点倾斜和变形的影响。局部区域的研究表明，在SLF-BFS中，压缩波明显收敛为再附着激波的出现是由于局地对流马赫数和自由剪切层k - h涡的诱导。然而，在STF-BFS中，压缩波和k - h涡几乎不明显，再附着激波的形成与壁面压缩效应有关。
Fine structures of supersonic flow over a 5 mm high backward facing step (BFS), including expansion wave fan, reattachment shock, supersonic boundary layer were measured in aMa=3.0 low-noise indraft wind tunnel. By varying the superficial roughness of the wall upstream from the step, supersonic laminar flow and supersonic turbulent flow could be formed over a BFS. Measurements on the spatiotemporal features of the holistic flow field and the fine structures in four typical regions were carried out using NPLS (nano-based planar laser scattering). Flow structures, including expansion wave fan, reattachment shock, supersonic boundary layer and its separation, reattachment and redevelopment are revealed by measuring the holistic structure of the transient flow field. Comparing the two time-averaged flow fields with each other, it is apparent that supersonic turbulent flow over a BFS (STF-BFS) has a larger expansion angle and a shorter recirculation region, and its redeveloped boundary layer increases at a smaller obliquity while the angle of reattachment shock is the same for the supersonic laminar flow over a BFS (SLF-BFS). With regard to time-evolution features, theK-Hvortices in the SLF-BFS suffers from shearing, expansion, reattachment and three-dimensional effects while in the STF-BFS large-scale structures are affected by the incline and distortion at the reattachment point due to expansion, viscosity and reverse-pressure. Studies on local regions indicate that in the SLF-BFS, the emergence of compression waves which distinctly converge into a reattachment shock is due to the local convective Mach number and the inducement ofK-Hvortices in the free shear layer. Nevertheless, in the STF-BFS, compression waves andK-Hvortices are barely evident, and the formation of a reattachment shock is related to the wall compressive effect.
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影响因子：
2.4
作者：
G. Shen;G. Ma
通讯作者：
G. Shen;G. Ma
DOI：
10.1023/b:appl.0000014915.18571.06
发表时间：
2003-03
期刊：
Flow, Turbulence and Combustion
影响因子：
--
作者：
J. Neumann;H. Wengle
通讯作者：
J. Neumann;H. Wengle
影响因子：
2.4
作者：
N. Furuichi;T. Hachiga;M. Kumada
通讯作者：
N. Furuichi;T. Hachiga;M. Kumada
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
DOI：
10.2514/6.1996-322
发表时间：
1996-01
期刊：
--
影响因子：
--
作者：
Jeffrey S. Cohen;J. Bennett
通讯作者：
Jeffrey S. Cohen;J. Bennett