NPLS Based Experimental Investigation on Fine Flow Structures over Supersonic Backward-Facing-Step under Interference of Oblique Shock Wave

被引：0
|
作者：
Luo X.-Q. [1 ]
Zhu Y.-Z. [1 ,2 ,3 ]
Lin W. [1 ]
Wang H.-T. [1 ]
Tong Y.-H. [1 ]
Shi Q. [1 ]
机构：
[1] Department of Aerospace Science and Technology, College Space Engineering University, Beijing
[2] State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact, PLA Engineering University, Nanjing
[3] China Astronaut Research and Training Center, Beijing
来源：
Tuijin Jishu/Journal of Propulsion Technology | 2022年 / 43卷 / 12期
关键词：
Backward-facing-step; Boundary layer; Large scale structure; Nano-tracer-based planar laser scattering; Oblique shock wave; Supersonic;
D O I：
10.13675/j.cnki.tjjs.210384
中图分类号：
学科分类号：
摘要：
In order to analyze the law of interaction between oblique shock wave and flow around steps after supersonic speed, in a small low-noise wind tunnel with Ma=3.8, experimental studies with step heights of 5mm and 10mm were carried out. Nano-tracer-based planar laser scattering (NPLS) technology was used to obtain the fine flow structure images. An oblique wedge is installed on the upper surface of the upstream flow field to generate oblique shock waves. The interference effects of oblique shock waves with different incident angles and acting positions on the backward-facing-step (BFS) flow structure of different heights were compared. Without oblique shock interference, the shear layer near the steps flows into a wide range of low-velocity areas. However, when the oblique shock wave acts on the redeveloping boundary layer, the flow inverse pressure gradient downstream of the step is significant. As a result, the boundary layer after the shock wave significantly lifts, forming a large number of large-scale/coherent vortex structures. The movement speed of the large-scale structure is about 20% lower than that of the incoming flow, and the developing period is larger than 20μs. After the point of action the flow accelerates almost to the mainstream speed. The oblique shock wave reflects on the boundary layer. The shape of the reflected shock wave is severely distorted, and many irregular small shock wave structures are induced simultaneously. © 2022 Journal of Propulsion Technology. All rights reserved.
引用
收藏
相关论文
共 28 条
  • [1] (2015)
  • [2] (2015)
  • [3] Scherberg M G, Smith H E., An Experimental Study of Supersonic Flow over a Rearward Facing Step, AIAA Journal, 5, 1, pp. 51-56, (2012)
  • [4] Arai T, Sugiyama H, Homareda M, Et al., Turbulence Characteristics of Supersonic Boundary Layer Past a Backward Facing Step, (1995)
  • [5] Rom J, Seginer A., Laminar Heat Transfer to a Two-Dimensional Backward Facing Step from the High-Enthalpy Supersonic Flow in the Shock Tube, AIAA Journal, 2, 2, pp. 251-255, (2015)
  • [6] Baker P J, Martin B W., Heat Transfer in Supersonic Separated Flow over a Two-Dimensional Backward-Facing Step, International Journal of Heat and Mass Transfer, 9, 10, pp. 1081-1088, (1966)
  • [7] Correa S, Warren R., Supersonic Sudden-Expansion Flow with Fluid Injection-An Experimental and Computational Study, (1989)
  • [8] Gai S L, Reynolds N T, Ross C, Et al., Measurements of Heat Transfer in Separated Highenthalpy Dissociated Laminar Hypersonic Flow Behind a Step, Journal of Fluid Mechanics, 199, pp. 541-561, (1989)
  • [9] Leontiev A I, Popovich S S, Vinogradov Y A, Et al., Experimental Research of Supersonic Flow Heat Transfer in the Wake of a Backward-Facing Step, Journal of Physics: Conference Series, 1369, 1, (2019)
  • [10] (2014)
123