Underwater oblique shock wave reflection

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Ritwik Ghoshal ◽  
Nilanjan Mitra
Keyword(s):  
Shock Wave ◽  
Wave Reflection ◽  
Oblique Shock ◽  
Oblique Shock Wave ◽  
Shock Wave Reflection

scholarly journals Oblique shock wave reflection at plasma array presence

2021 ◽  
Vol 2100 (1) ◽  
pp. 012008
Author(s):  
S Elliott ◽  
A A Firsov ◽  
S B Leonov
Keyword(s):  
Shock Wave ◽  
Test Section ◽  
Wave Reflection ◽  
Separation Zone ◽  
Plasma Generator ◽  
Oblique Shock ◽  
Oblique Shock Wave ◽  
Stagnation Temperature ◽  
Shock Wave Reflection ◽  
The University

Abstract This work discusses the effect of a filamentary plasma array on shock wave (SW) reflection pattern and on a shock-induced separation zone geometry. It includes experimental and computational components both. The experimentation was performed in the supersonic blowdown test rig SBR-50 at the University of Notre Dame at flow Mach number M=2, stagnation pressure P0=1.7-2.7 bar and stagnation temperature T0=300 K. Oblique shock wave generator composed of a symmetric solid wedge was installed on the top wall of test section while the filamentary plasma generator was arranged on the opposite wall. Thus, the main SW originating from the wedge impinged the plasma area. As a result of the SW-plasma interaction, the flowfield was significantly modified, including a shift of the main SW upstream and redistribution of wall pressure over the test section. The computational analysis allowed a 3D reconstruction of the SW interaction with the plasma array. The physics of SW-plasma array interaction are also discussed.

Nonequilibrium effects in oblique shock-wave reflection

AIAA Journal ◽  
1988 ◽  
Vol 26 (6) ◽  
pp. 698-705 ◽  
Author(s):  
Harland M. Glaz ◽  
Phillip Colella ◽  
James P. Collins ◽  
Ralph E. Ferguson
Keyword(s):  
Shock Wave ◽  
Wave Reflection ◽  
Oblique Shock ◽  
Oblique Shock Wave ◽  
Shock Wave Reflection ◽  
Nonequilibrium Effects

Pseudostationary oblique shock-wave reflections in sulphur hexafluoride (SF 6 ): interferometric and numerical results

1986 ◽  
Vol 408 (1835) ◽  
pp. 321-344 ◽  
Keyword(s):  
Shock Wave ◽  
Mach Number ◽  
Triple Point ◽  
Wave Reflection ◽  
Incident Shock ◽  
Oblique Shock Wave ◽  
Wave Reflections ◽  
Shock Wave Reflection ◽  
Wedge Surface ◽  
Vibrational Equilibrium

Pseudostationary oblique shock-wave reflections in SF 6 were investigated experimentally and numerically. Experiments were concluded in the UTIAS 10 x 18 cm Hypervelocity Shock Tube in the range of incident shock wave Mach number 1.25 < M s < 8.0 and wedge angle 4° < θ w < 47° with initial pressure 4 < P 0 < 267 Torr (0.53-35.60 kPa) at temperatures T 0 near 300 K. The four major types of shock-wave reflection, i. e. regular reflection (RR), single-Mach (SMR), complex-Mach (CMR) and double-Mach reflections (DMR), were observed. These were studied by using infinite-fringe interferograms from a Mach-Zehnder interferometer with a 23 cm diameter field of view. The isopycnics and the density distributions along the wedge surface are presented for the various types of reflection. The analytical transition boundaries between the four types of shock-wave reflection were established up to M s = 10.0 for frozen and equilibrium vibrational SF 6 . An examination of the relaxation length under the present experimental conditions indicated that a vibrational-equilibrium analysis was required. Comparisons of experiment with analysis for transition-boundary maps, reflection angle δ and the first triple-point trajectory angle X verify that the reflections were in vibrational equilibrium. The excellent agreement between the present interferometric results and the numerical results obtained by H. M. Glaz et al . ( Proc. int. colloq. on dynamics of explosives and reactive systems [ Berkeley ] (1985)) with real-gas effects also supports the vibrational equilibrium hypothesis for shocked SF 6 . The behaviour of the angle between the two triple-point trajectories ( X ' — X ) is discussed and the unique pattern of DMR with X ' = 0 was verified experimentally. A numerical analysis for the second triple-point system is obtained for the first time. It is shown that, for a given incident shock Mach number, the highest wedge-surface pressure is achieved through a DMR instead of an RR at high M s .

scholarly journals Numerical and experimental investigation of oblique shock wave reflection off a water wedge

2017 ◽  
Vol 826 ◽  
pp. 732-758 ◽  
Author(s):  
Q. Wan ◽  
H. Jeon ◽  
R. Deiterding ◽  
V. Eliasson
Keyword(s):  
Shock Wave ◽  
Triple Point ◽  
Wave Reflection ◽  
Wave Interaction ◽  
Analytic Solutions ◽  
Incident Shock ◽  
Incident Shock Wave ◽  
Oblique Shock Wave ◽  
Shock Wave Reflection ◽  
Mach Numbers

Shock wave interaction with solid wedges has been an area of much research in past decades, but so far very few results have been obtained for shock wave reflection off liquid wedges. In this study, numerical simulations are performed using the inviscid Euler equations and the stiffened gas equation of state to study the transition angles, reflection patterns and triple point trajectory angles of shock reflection off solid and water wedges. Experiments using an inclined shock tube are also performed and schlieren photography results are compared to simulations. Results show that the transition angles for the water wedge cases are within 5.3 % and 9.2 %, for simulations and experiments respectively, compared to results obtained with the theoretical detachment criterion for solid surfaces. Triple point trajectory angles are measured and compared with analytic solutions, agreement within $1.3^{\circ }$ is shown for the water wedge cases. The transmitted wave in the water observed in the simulation is quantitatively studied, and two different scenarios are found. For low incident shock Mach numbers, $M_{s}=1.2$ and 2, no shock wave is formed in the water but a precursor wave is induced ahead of the incident shock wave and passes the information from the water back into the air. For high incident shock Mach numbers, $M_{s}=3$ and 4, precursor waves no longer appear but instead a shock wave is formed in the water and attached to the Mach stem at every instant. The temperature field in the water is measured in the simulation. For strong incident shock waves, e.g. $M_{s}=4$, the temperature increment in the water is up to 7.3 K.

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