OBLIQUE SHOCK WAVE INCIDENCE ON A PLATE (TWO-DIMENSIONAL FLOW)

2018 ◽  
Author(s):  
Ivan Egorov
Keyword(s):  
Shock Wave ◽  
Oblique Shock ◽  
Oblique Shock Wave ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Two Dimensional Flow ◽  
Wave Incidence

Iterative Solutions of the Equations Jor Plane Oblique Shock Waves

1959 ◽  
Vol 63 (587) ◽  
pp. 669-672 ◽  
Author(s):  
A. R. Collar
Keyword(s):  
Shock Wave ◽  
Mach Number ◽  
Supersonic Flow ◽  
Free Stream ◽  
Oblique Shock ◽  
Oblique Shock Wave ◽  
Two Dimensional ◽  
Iterative Solutions ◽  
Flow Through ◽  
Image Position

If a plane oblique shock wave, inclined to the free stream at the angle ε, is produced in two-dimensional supersonic flow of Mach number M by (for example) a wedge which deflects the flow through an angle δ, the equation connecting these quantities may be writtenIn this form, δ is given explicitly when M, ε are fixed. Similarly, we may obtain M explicitly when ε, δ are fixed; equation (1) may be written (see, for example, Liepmann and Puckett, Equation 4.27)

scholarly journals Instabilities in oblique shock wave/laminar boundary-layer interactions

2016 ◽  
Vol 789 ◽  
pp. 1-35 ◽  
Author(s):  
F. Guiho ◽  
F. Alizard ◽  
J.-Ch. Robinet
Keyword(s):  
Boundary Layer ◽  
Shock Wave ◽  
Shear Layer ◽  
Laminar Boundary Layer ◽  
Oblique Shock ◽  
Oblique Shock Wave ◽  
Two Dimensional ◽  
Linear Framework ◽  
Displacement Thickness ◽  
The Impact

The interaction of an oblique shock wave and a laminar boundary layer developing over a flat plate is investigated by means of numerical simulation and global linear-stability analysis. Under the selected flow conditions (free-stream Mach numbers, Reynolds numbers and shock-wave angles), the incoming boundary layer undergoes separation due to the adverse pressure gradient. For a wide range of flow parameters, the oblique shock wave/boundary-layer interaction (OSWBLI) is seen to be globally stable. We show that the onset of two-dimensional large-scale structures is generated by selective noise amplification that is described for each frequency, in a linear framework, by wave-packet trains composed of several global modes. A detailed analysis of both the eigenspectrum and eigenfunctions gives some insight into the relationship between spatial scales (shape and localization) and frequencies. In particular, OSWBLI exhibits a universal behaviour. The lowest frequencies correspond to structures mainly located near the separated shock that emit radiation in the form of Mach waves and are scaled by the interaction length. The medium frequencies are associated with structures mainly localized in the shear layer and are scaled by the displacement thickness at the impact. The linear process by which OSWBLI selects frequencies is analysed by means of the global resolvent. It shows that unsteadiness are mainly associated with instabilities arising from the shear layer. For the lower frequency range, there is no particular selectivity in a linear framework. Two-dimensional numerical simulations show that the linear behaviour is modified for moderate forcing amplitudes by nonlinear mechanisms leading to a significant amplification of low frequencies. Finally, based on the present results, we draw some hypotheses concerning the onset of unsteadiness observed in shock wave/turbulent boundary-layer interactions.

Three-dimensional effects in wind tunnel studies of shock wave reflection

2000 ◽  
Vol 407 ◽  
pp. 85-104 ◽  
Author(s):  
B. W. SKEWS
Keyword(s):  
Shock Wave ◽  
Wave Reflection ◽  
Wedge Angle ◽  
Three Dimensional ◽  
Wave System ◽  
Two Dimensional ◽  
Shock Wave Reflection ◽  
Dimensional Flow ◽  
Dimensional Effects ◽  
Two Dimensional Flow

This paper concentrates on establishing the three-dimensional flow geometry associated with studies of shock wave reflection between two symmetrical wedges in supersonic flow. It considers the issue of hysteresis in such flows, and draws a distinction between three different aspects of hysteresis, associated with: ideal two-dimensional flow, flow with noise, and three-dimensional effects. The three-dimensional nature of the flow field is elucidated by the use of oblique shadowgraph photography where the optical axis of the shadowgraph system passes at an oblique angle, of as much as 55°, through the test section. The traces of the wave system reflecting off the tunnel window are identified and are used to assist in identification of wave profiles. The nature of the approach of the peripheral Mach reflections collapsing towards the centre of the flow becomes evident, as does the mechanism of transition from Mach reflection to regular reflection. Distinct evidence of the effects of flow perturbations at the mechanical equilibrium transition point are presented, as are changes in the rate of growth of the Mach stem near this point.It is shown that three-dimensional effects can have a major effect on the wedge angle for transition. In the present tests, at Mach 3.1 and a wedge aspect ratio of 0.5, this occurs at a wedge angle of about 5° higher than the theoretical maximum for the corresponding two-dimensional flow, where the dual solution domain extends over only two degrees.

scholarly journals Simulation of flow field in steam ejector and analysis of shock wave characteristics

2018 ◽  
Vol 198 ◽  
pp. 03001
Author(s):  
Yi Cui
Keyword(s):  
Shock Wave ◽  
Flow Field ◽  
Back Pressure ◽  
Two Dimensional ◽  
Dimensional Flow ◽  
Wave Characteristics ◽  
Steam Ejector ◽  
Two Dimensional Flow ◽  
Fluent Software ◽  
Throat Diameter

Fluent software is used to simulate the two-dimensional flow field in the steam ejector. The generation, development and end of shock in the flow field are analyzed. The influence of the shock wave characteristics on the ejector performance is discussed. The results show that the working back pressure in the steam ejector and the throat diameter of the nozzle all affect the position and intensity of the shock wave. When the shock wave ends prematurely or belatedly , it all affect the performance of the injector.

Analytical investigation of two-dimensional unsteady shock-on-shock interactions

1997 ◽  
Vol 340 ◽  
pp. 101-128 ◽  
Author(s):  
H. LI ◽  
G. BEN-DOR
Keyword(s):  
Shock Wave ◽  
Mach Reflection ◽  
Analytical Investigation ◽  
Vehicle Body ◽  
Oblique Shock Wave ◽  
Pressure Jump ◽  
Two Dimensional ◽  
Shock Interactions ◽  
Two Dimensional Flow ◽  
Transition Criterion

The unsteady inviscid two-dimensional flow field and the wave configurations which result when a supersonic vehicle strikes a planar oblique shock wave were modelled and analytically predicted using some approximations and simplifying assumptions. Based on the two- and three-shock theories together with the geometric shock dynamics theory, both regular (windward) and irregular (leeward) shock-on-shock (S-O-S) interactions were investigated, and the transition criterion between them was suggested. For the case of regular S-O-S interaction, the transmitted shock wave reflects over the vehicle body surface either as a regular (RR) or a Mach reflection (MR) depending on the inclination angle and the strength of the impingement shock wave. A pronounced peak surface pressure jump was found to exist during the transition from RR to MR. A RR[harr ]MR transition criterion when the flow ahead of the shock pattern is not quiescent was proposed. Predictions based on the model developed here are superior to those of approximate theories when compared to the available experimental data and numerical simulations.

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