Design and analysis of the scramjet nozzle with contact discontinuity

In this paper, we study the intersection (interaction) between several steady shocks traveling in the same direction. The interaction between overtaking shocks may be regular or irregular. In the case of regular reflection, the intersection of overtaking shocks leads to the formation of a resulting shock, contact discontinuity, and some reflected discontinuities. The type of discontinuity depends on the parameters of incoming shocks. At the irregular reflection, a Mach shock forms between incoming overtaking shocks. Reflected discontinuities come from the points of intersection of the Mach stem with the incoming shocks. We also consider the possible types of shockwave configurations that form both at regular and irregular interactions of several overtaking shocks. The regions of existence of overtaking shock waves with different types of reflected shock and the intensity of reflected shocks are defined. The results obtained in the study can potentially be useful for designing supersonic intakes and advanced jet engines.

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Detonation-to-shock wave transmission at a contact discontinuity

Shock Waves ◽

10.1007/s00193-018-0804-6 ◽

2018 ◽

Vol 28 (5) ◽

pp. 981-992 ◽

Cited By ~ 4

Author(s):

J. T. Peace ◽

F. K. Lu

Keyword(s):

Shock Wave ◽

Contact Discontinuity ◽

Wave Transmission

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Collision of merger and accretion shocks: formation of Mpc-scale contact discontinuity in the Perseus cluster

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slaa147 ◽

2020 ◽

Vol 498 (1) ◽

pp. L130-L134

Author(s):

Congyao Zhang ◽

Eugene Churazov ◽

Klaus Dolag ◽

William R Forman ◽

Irina Zhuravleva

Keyword(s):

Contact Discontinuity ◽

Alternative Scenario ◽

X Ray ◽

Cold Fronts ◽

Contact Discontinuities ◽

Accretion Shock ◽

Perseus Cluster ◽

Accretion Shocks

ABSTRACT Two Mpc-size contact discontinuities have recently been identified in the XMM–Newton and Suzaku X-ray observations in the outskirts of the Perseus cluster (Walker et al.). These structures have been tentatively interpreted as ‘sloshing cold fronts’, which are customarily associated with differential motions of the cluster gas, perturbed by a merger. In this study, we consider an alternative scenario, namely, that the most prominent discontinuity, near the cluster virial radius, is the result of the collision between the accretion shock and a ‘runaway’ merger shock. We also discuss the possible origin of the second discontinuity at ${\sim}1.2{\rm \, Mpc}$.

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Magnetic Rayleigh–Taylor instability at a contact discontinuity with an oblique magnetic field

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936490 ◽

2020 ◽

Vol 634 ◽

pp. A96

Author(s):

E. Vickers ◽

I. Ballai ◽

R. Erdélyi

Keyword(s):

Magnetic Field ◽

Growth Rate ◽

Dispersion Relation ◽

Contact Discontinuity ◽

Homogeneous Magnetic Field ◽

Taylor Instability ◽

Wide Range ◽

Rayleigh Taylor Instability ◽

The Magnetic Field ◽

Theoretical Results

Aims. We investigate the nature of the magnetic Rayleigh–Taylor instability at a density interface that is permeated by an oblique homogeneous magnetic field in an incompressible limit. Methods. Using the system of linearised ideal incompressible magnetohydrodynamics equations, we derive the dispersion relation for perturbations of the contact discontinuity by imposing the necessary continuity conditions at the interface. The imaginary part of the frequency describes the growth rate of waves due to instability. The growth rate of waves is studied by numerically solving the dispersion relation. Results. The critical wavenumber at which waves become unstable, which is present for a parallel magnetic field, disappears because the magnetic field is inclined. Instead, waves are shown to be unstable for all wavenumbers. Theoretical results are applied to diagnose the structure of the magnetic field in prominence threads. When we apply our theoretical results to observed waves in prominence plumes, we obtain a wide range of field inclination angles, from 0.5° up to 30°. These results highlight the diagnostic possibilities that our study offers.

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Field-line reconnexion in the two-dimensional asymmetric case

Journal of Plasma Physics ◽

10.1017/s0022377800001215 ◽

1983 ◽

Vol 30 (2) ◽

pp. 321-344 ◽

Cited By ~ 17

Author(s):

V. S. Semenov ◽

I. V. Kubyshkin ◽

M. F. Heyn ◽

H. K. Biernat

Keyword(s):

Shock Wave ◽

Shock Waves ◽

Contact Discontinuity ◽

Two Dimensional ◽

Rarefaction Waves ◽

Plasma Parameters ◽

Different Types ◽

Asymmetric Case ◽

Detailed Mathematical Analysis ◽

Alfven Velocity

A detailed mathematical analysis of plane steady-state reconnexion is given for the case when the plasma parameters and the magnetic fields are not identical on both sides of the current sheet. Asymptotic solutions in the sense that the inflow velocity is much less than the local Alfvén velocity as well as the arrangement of shock waves are obtained. Rotational (Alfvén) waves, slow shock waves, rarefaction waves (expansion fans), and a contact discontinuity may occur. Four different types of solution, corresponding to different shock wave configurations, are possible. They depend on the parameters of the inflow regions in a unique way.

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