Evolution of artificial disturbances in a shear layer at M=1.43

Abstract The evolution of artificial disturbances in a laminar boundary layer on a flat plate model in the presence of an incident shock wave is considered. The flow is supersonic with the freestream Mach number M = 1.43. The study is carried out by hot-wire anemometry. A dielectric barrier discharge is used to generate disturbances. Data on the distribution in space of the average and non-stationary components of the mass flow are obtained. Disturbances created by the discharge and their evolution along the separation zone are recorded.

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Visualization of hypersonic incident shock wave boundary layer interaction

Journal of Visualization ◽

10.1007/s12650-019-00622-0 ◽

2020 ◽

Vol 23 (2) ◽

pp. 207-214 ◽

Cited By ~ 2

Author(s):

Zhang Qinghu ◽

Zhu Zhiwei ◽

Lin Jingzhou ◽

Xie Futian ◽

Zhong Jun

Keyword(s):

Boundary Layer ◽

Shock Wave ◽

Incident Shock ◽

Incident Shock Wave ◽

Layer Interaction ◽

Wave Boundary Layer ◽

Boundary Layer Interaction ◽

Wave Boundary

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Visualization of the structure of an incident shock wave/turbulent boundary layer interaction

Shock Waves ◽

10.1007/s00193-014-0530-7 ◽

2014 ◽

Vol 24 (6) ◽

pp. 583-592 ◽

Cited By ~ 6

Author(s):

L. He ◽

S. Yi ◽

Z. Chen ◽

Y. Zhu

Keyword(s):

Boundary Layer ◽

Shock Wave ◽

Turbulent Boundary Layer ◽

Incident Shock ◽

Incident Shock Wave ◽

Layer Interaction ◽

Boundary Layer Interaction

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ON THE GASDYNAMIC MECHANISMS OF EXOTHERMIC REACTION WAVE FORMATION BEHIND SHOCK WAVES

NONEQUILIBRIUM PROCESSES. Vol. 2. Fundamentals of combustion ◽

10.30826/nepcap2018-2-20 ◽

2020 ◽

Author(s):

A. Kiverin ◽

◽

I. Yakovenko ◽

Keyword(s):

Boundary Layer ◽

Shock Wave ◽

Gas Flow ◽

Exothermic Reaction ◽

Incident Shock ◽

Incident Shock Wave ◽

Wave Formation ◽

Mixture Flow ◽

Reflected Shock ◽

Reaction Wave

The paper analyzes the gasdynamic evolution of the test mixture flow in the shock tube at the stage prior to reaction start. The numerical analysis clearly shows that the incepience of reaction kernels is associated with the specific features of flow development in the boundary layer behind an incident shock wave. It is shown that similar to the processes in the gas flow near a solid surface, the gasdynamic instability arises and develops in the flow behind a shock wave. The linear stage of instability development determines the formation of roll-up vortices at a certain distance behind the shock front. Further, at the nonlinear stage, these roll-up vortices transform in more complex structures that diffuse into the bulk flow. Evolution of vortices causes temperature redistribution on the scales of the boundary layer. On the one hand, there is a certain heating due to the kinetic energy dissipation. On the other hand, there are heat losses to the wall. As a result, the temperature field near the wall becomes nonuniform. The reflected shock amplifies temperature perturbations when interacts with the developed boundary layer. This mechanism determines the formation of hot kernels in which the reaction starts. So, the localized sites of exothermal reaction are arising providing conditions for reaction wave formation and propagation in the precompressed test gas.

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A study on the focusing phenomenon of a weak shock wave

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/095440603771665241 ◽

2003 ◽

Vol 217 (11) ◽

pp. 1209-1220 ◽

Cited By ~ 3

Author(s):

H-D Kim ◽

Y-H Kweon ◽

T Setoguchi ◽

S Matsuo

Keyword(s):

Shock Wave ◽

Mach Number ◽

Peak Pressure ◽

Weak Shock ◽

Incident Shock ◽

Incident Shock Wave ◽

Weak Shock Wave ◽

Tvd Scheme ◽

Local Pressure ◽

Gas Dynamic

When a plane shock wave reflects from a concave wall or when a curved shock wave reflects from a straight wall, it is focused at a certain location, resulting in extremely high local pressure and temperature. This focusing is due to a non-linear phenomenon of a shock wave. This focusing phenomenon has been extensively applied in a variety of engineering and medical areas. In the current study, the focusing phenomenon of a weak shock wave over a reflector is numerically investigated using a computational fluid dynamics (CFD) method. The total variation diminishing (TVD) scheme is used to solve the unsteady, two-dimensional, compressible, Euler equations. The Mach number of the incident shock wave is changed in the range from 1.1 to 1.5. Several different types of reflectors are employed to investigate the effect of the reflector on the focusing phenomenon of the weak shock wave. The focusing characteristics of the shock wave are investigated in terms of peak pressure, gas dynamic and geometrical foci. The results obtained are compared with previous experiment results that are available. The results show that the peak pressure of shock wave focusing and its location strongly depend on the Mach number of the incident shock wave and the reflector geometry. The location of the gas dynamic focus is always shorter than that of the geometrical one. This tendency is more remarkable as the incident shock wave becomes stronger. The present computations predict the experimental results with a very good accuracy.

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Unsteady aspects of an incident shock wave/turbulent boundary layer interaction

Journal of Fluid Mechanics ◽

10.1017/s0022112009007630 ◽

2009 ◽

Vol 635 ◽

pp. 47-74 ◽

Cited By ~ 43

Author(s):

R. A. HUMBLE ◽

F. SCARANO ◽

B. W. van OUDHEUSDEN

Keyword(s):

Boundary Layer ◽

Shock Wave ◽

Turbulent Boundary Layer ◽

Incident Shock ◽

Incident Shock Wave ◽

Reflected Shock Wave ◽

Reversed Flow ◽

Layer Interaction ◽

Reflected Shock ◽

Boundary Layer Interaction

An incident shock wave/turbulent boundary layer interaction at Mach 2.1 is investigated using particle image velocimetry in combination with data processing using the proper orthogonal decomposition, to obtain an instantaneous and statistical description of the unsteady flow organization. The global structure of the interaction is observed to vary considerably in time. Although reversed flow is often measured instantaneously, on average no reversed flow is observed. On an instantaneous basis, the interaction exhibits a multi-layered structure, characterized by a relatively high-velocity outer region and low-velocity inner region. Discrete vortical structures are prevalent along their interface, which create an intermittent fluid exchange as they propagate downstream. A statistical analysis suggests that the instantaneous fullness of the incoming boundary layer velocity profile is (weakly) correlated with the size of the separation bubble and position of the reflected shock wave. The eigenmodes show an energetic association between velocity fluctuations within the incoming boundary layer, separated flow region and across the reflected shock wave, and portray subspace features that represent the phenomenology observed within the instantaneous realizations.

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