Rarefaction shock wave near the critical liquid–vapour point

1983 ◽  
Vol 126 ◽  
pp. 59-73 ◽  
Author(s):  
A. A. Borisov ◽  
Al. A. Borisov ◽  
S. S. Kutateladze ◽  
V. E. Nakoryakov
Keyword(s):  
Shock Wave ◽  
Shock Tube ◽  
Critical Point ◽  
Wave Front ◽  
Propagation Velocity ◽  
Test Substance ◽  
Unperturbed State ◽  
Long Wave ◽  
Rarefaction Shock ◽  
Negative Shock

The existence of a rarefaction shock wave or negative shock wave in a substance whose unperturbed state is close to the thermodynamic critical liquid–vapour point has been demonstrated experimentally. Its evolution and propagation velocity in a shock tube with Freon-13 as the test substance are described. It is shown that the steepness of the wave front does not diminish as the wave evolves. An equation is derived that describes the evolution of long-wave perturbations near the critical point.

Three-dimensional shock tube flows for dense gases

2007 ◽  
Vol 583 ◽  
pp. 423-442 ◽  
Author(s):  
ALBERTO GUARDONE
Keyword(s):  
Shock Wave ◽  
Shock Tube ◽  
Shock Front ◽  
Numerical Simulations ◽  
Three Dimensional ◽  
Dense Gas ◽  
Complex Flow ◽  
The Many ◽  
The One ◽  
Rarefaction Shock

The formation process of a non-classical rarefaction shock wave in dense gas shock tubes is investigated by means of numerical simulations. To this purpose, a novel numerical scheme for the solution of the Euler equations under non-ideal thermodynamics is presented, and applied for the first time to the simulation of non-classical fully three-dimensional flows. Numerical simulations are carried out to study the complex flow field resulting from the partial burst of the shock tube diaphragm, a situation that has been observed in preliminary trials of a dense gas shock tube experiment. Beyond the many similarities with the corresponding classical flow, the non-classical wave field is characterized by the occurrence of anomalous compression isentropic waves and rarefaction shocks propagating past the leading rarefaction shock front. Negative mass flow through the rarefaction shock wave results in a limited interaction with the contact surface close to the diaphragm, a peculiarity of the non-classical regime. The geometrical asymmetry does not prevent the formation of a single rarefaction shock front, though the pressure difference across the rarefaction wave is predicted to be weaker than the one which would be obtained by the complete burst of the diaphragm.

Theory for producing a single-phase rarefaction shock wave in a shock tube

2001 ◽  
Vol 445 ◽  
pp. 37-54 ◽  
Author(s):  
S. H. FERGASON ◽  
T. L. HO ◽  
B. M. ARGROW ◽  
G. EMANUEL
Keyword(s):  
Shock Wave ◽  
Mach Number ◽  
Shock Tube ◽  
Single Phase ◽  
Van Der Waals ◽  
Small Region ◽  
Incident Flow ◽  
Global Theory ◽  
Rarefaction Shock ◽  
Shock Tube Experiment

Although predicted early in the 20th century, a single-phase vapour rarefaction shock wave has yet to be demonstrated experimentally. Results from a previous shock tube experiment appear to indicate a rarefaction shock wave. These results are discussed and their interpretation challenged. In preparation for a new shock tube experiment, a global theory is developed, utilizing a van der Waals fluid, for demonstrating a single-phase vapour rarefaction shock wave in the incident flow of the shock tube. The flow consists of four uniform regions separated by three constant-speed discontinuities: a rarefaction shock, a compression shock, and a contact surface. Entropy jumps and upstream supersonic Mach number conditions are verified for both shock waves. The conceptual van der Waals model is applied to the fluid perfluoro-tripentylamine (FC-70, C15F33N) analytically, and verified with computational simulations. The analysis predicts a small region of initial states that may be used to unequivocally demonstrate the existence of a single-phase vapour rarefaction shock wave. Simulation results in the form of representative sets of thermodynamic state data (pressure, density, Mach number, and fundamental derivative of gas dynamics) are presented.

Simulation of Interaction between a Spherical Shock Wave and a Layer of Granular Material in a Conical Shock Tube

2021 ◽  
Vol 15 (4) ◽  
pp. 685-690
Author(s):  
S. V. Khomik ◽  
I. V. Guk ◽  
A. N. Ivantsov ◽  
S. P. Medvedev ◽  
E. K. Anderzhanov ◽  
...  
Keyword(s):  
Shock Wave ◽  
Granular Material ◽  
Shock Tube ◽  
Spherical Shock Wave ◽  
Conical Shock ◽  
Spherical Shock

Numerical Simulation of Air Flow in the State of Thermal and Chemical Nonequilibrium behind a Shock Wave Front

2021 ◽  
pp. 94-111
Author(s):  
A.I. Bryzgalov
Keyword(s):  
Shock Wave ◽  
Shock Front ◽  
Wave Front ◽  
Shock Wave Front ◽  
Reaction Rate ◽  
Vibrational Temperature ◽  
Pure Oxygen ◽  
Published Data ◽  
Calculation Results ◽  
Temperature Nonequilibrium

We used the model of a five-component air mixture flow behind the front of a one-dimensional shock wave to compute the flow parameters for shock front temperatures of up to 7000 K, taking into account the variable composition, translational and vibrational temperatures and pressure in the relaxation zone. Vibrational level population in oxygen and nitrogen obeys the Boltzmann distribution with one common vibrational temperature. We consider the effect that temperature nonequilibrium has on the chemical reaction rate by introducing a nonequilibrium factor to the reaction rate constant, said factor depending on the vibrational and translational temperatures. We compared our calculation results for dissociation behind the shock front to the published data concerning temperature nonequilibrium in a pure oxygen flow behind a shock wave front for two different intensities of the latter. The comparison shows a good agreement between the vibrational temperature, experimental data and calculations based on the experimental values of vibrational temperature and molality. We computed the parameters of thermodynamically nonequilibrium dissociation in the air behind the shock wave front, comparing them to those of equilibrium dissociation and calculation results previously published by others. The study demonstrates that the molality values computed converge gradually with those found in published data as the distance from the shock front increases. We list the reasons for the discrepancy between our calculation results and previously published data

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