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1.
Enhancement of shock waves in a porous medium saturated with a liquid containing soluble-gas bubbles 总被引:5,自引:0,他引:5
Evolution of a moderate-intensity shock wave and its enhancement after reflection from a rigid surface embedded in a porous medium are studied experimentally. The medium is saturated with a liquid that has bubbles of a soluble gas. A physical mechanism of shock wave enhancement in a saturated porous medium is proposed. Experimental data on the amplitude and velocity of reflected waves are compared with results of theoretical modeling. The process of gas bubble dissolution behind a shock wave is studied. 相似文献
2.
V. E. Dontsov V. E. Nakoryakov 《Journal of Applied Mechanics and Technical Physics》2000,41(5):845-854
The process of evolution and reflection of shock waves of moderate amplitude from a rigid boundary in a porous medium saturated
by a liquid with bubbles of a soluble gas is studied experimentally. Experimental values of the amplitude and velocity of
the reflected wave are compared with the calculated results obtained using mathematical models. The process of dissolution
of gas bubbles in the liquid behind the shock wave is studied.
Kutateladze Institute of Thermal Physics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 5, pp. 91–102, September–October, 2000. 相似文献
3.
4.
V. E. Dontsov V. E. Nakoryakov E. V. Dontsov 《Journal of Applied Mechanics and Technical Physics》2009,50(2):318-326
The processes of dissolution and hydrate formation behind a moderate-amplitude shock wave in water containing gas bubbles
(mixture of nitrogen and carbon dioxide) are studied in experiments with different initial static pressures in the medium
and concentrations of carbon dioxide in bubbles. An increase in static pressure in the gas-liquid medium is demonstrated to
enhance the influence of the non-reacting gas (nitrogen) on the processes of dissolution and hydrate formation.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 2, pp. 178–187, March–April, 2009. 相似文献
5.
V. E. Dontsov V. E. Nakoryakov A. A. Chernov 《Journal of Applied Mechanics and Technical Physics》2007,48(3):346-360
The evolution of a shock wave and its reflection from a wall in a gas-liquid medium with dissolution and hydration are experimentally
investigated. Dissolution and hydration behind the front of a moderate-amplitude shock wave are demonstrated to be caused
by fragmentation of gas bubbles, resulting in a drastic increase in the area of the interphase surface and in a decrease in
size of gas inclusions. The mechanisms of hydration behind the wave front are examined. Hydration behind the front of a shock
wave with a stepwise profile is theoretically analyzed.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 3, pp. 58–75, May–June, 2007. 相似文献
6.
7.
The problem of the mass, thermal and dynamic interaction between a bubble containing a soluble gas and a liquid is considered. It is shown that this problem can be reduced to the problem of the behavior of a vapor bubble with phase transitions investigated in detail in [1–3]. Expressions are obtained for the rate of decay of the radially symmetric oscillations of the bubbles due to the solubility of the gas in the liquid. The effective coefficients of mass transfer between the radially pulsating bubbles and the liquid are determined. A numerical solution is obtained for the problem of the radial motion of a bubble created by a sudden change of pressure in the liquid which, in particular, corresponds to the behavior of the bubbles behind the shock front when a shock wave enters a bubble screen.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 6, pp. 52–59, November–December, 1985. 相似文献
8.
9.
V. E. Dontsov 《Journal of Applied Mechanics and Technical Physics》1998,39(5):666-670
The present paper is concerned with an experimental study of the process of gas dissolution behind a shock wave in a liquid
with bubbles of a readily soluble gas, the influence of gas dissolution on the wave evolution, and strengthening of the shock
wave after reflection from a solid wall.
Kutateladze Institute of Thermal Physics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 5, pp. 19–24, September–October, 1998. 相似文献
10.
D. M. J. Smeulders J. P. M. De La Rosette M. E. H. Van Dongen 《Transport in Porous Media》1992,9(1-2):25-37
The propagation of compressional waves in a porous medium is investigated in case the pore liquid contains a small volume fraction of gas. The effect of oscillating gas bubbles is taken into account by introducing a frequency-dependent fluid bulk modulus, which is incorporated in the Biot theory. Using a shock tube technique, new experimental data are obtained for a porous column subjected to a pressure step wave. An oscillatory behaviour is observed, consisting of two distinct frequency bands, which is predicted by the theoretical analysis. 相似文献
11.
V. A. Kulikovskii 《Fluid Dynamics》1983,18(3):407-411
Analytic investigations into the damping of perturbations in dust-laden gas have been restricted to self-similar flows [1, 2] and flows with a symmetry plane, it being assumed in the latter case that thermal and velocity equilibrium of the phases is established instantaneously [3–6], i.e., the relaxation time of the medium is short. In the present paper, asymptotic laws of damping are obtained for plane, cylindrical, and spherical shock and continuous waves whose amplitude and width are such that the acceleration of the particles and the change in their temperature can be ignored. It is assumed that between the phases there is heat transfer proportional to the temperature difference and frictional momentum transfer proportional to the difference between the velocities of the phases. The obtained laws of damping of plane waves are found to be entirely analogous to the laws of damping of magnetohydrodynamic waves in a medium with finite conductivity, when the presence of Joule dissipation and the additional ponderomotive force in the traveling wave or in the gas flow behind the shock wave leads to exponential damping of the wave amplitude [7–9]. 相似文献
12.
Shock wave structure in a bubbly mixture composed of a cluster of gas bubbles in a quiescent liquid with initial void fractions
around 10% inside a 3D rectangular domain excited by a sudden increase in the pressure at one boundary is investigated using
the front tracking/finite volume method. The effects of bubble/bubble interactions and bubble deformations are, therefore,
investigated for further modeling. The liquid is taken to be incompressible while the bubbles are assumed to be compressible.
The gas pressure inside the bubbles is taken uniform and is assumed to vary isothermally. Results obtained for the pressure
distribution at different locations along the direction of propagation show the characteristics of one-dimensional unsteady
shock propagation evolving towards steady-state. The steady-state shock structures obtained by the present direct numerical
simulations, which show a transition from A-type to C-type steady-state shock structures, are compared with those obtained
by the classical Rayleigh–Plesset equation and by a modified Rayleigh–Plesset equation accounting for bubble/bubble interactions
in the mean-field theory.
相似文献
13.
The properties are studied of the propagation of unsteady shock waves in a gas-liquid system of bubble structure in the case when the volume concentration of the gas changes in the direction of motion of the shock wave. It is established that when there is a sufficiently rapid drop in the gas content, an effect of amplification of the shock wave is observed which is due to the deceleration of the medium behind the shock wave. A study is made of the laws of the evolution of long- and short-wave pulsed perturbations in such systems. The authors consider processes of reflection of waves from obstacles and their passage from a gas into a bubble liquid, from a two-phase mixture into a pure liquid. The contribution is determined of nonequilibrium effects to the process of amplification of a wave.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 49–54, January–February, 1988.The authors wish to express gratitude to R. I. Nigmatulin for his interest in the study and for useful discussions. 相似文献
14.
Measurements of film condensation were made behind the
incident shock wave
propagating through a vapor-liquid two-phase
medium. Major objective of the study
is to identify condensing heat transfer rates
of the vapor to the shock-tube side wall
as well as to learn the condensing main flow field.
Ethanol and E-10 (a heavy liquid
named Afluid by the manufacturer) were extensively
used as working fluid. Steady
accumulation of the condensing vapor was confirmed
on the wall surface, as similarly
seen in the end-wall experiment conducted elsewhere.
A most significant result is
that "dual-step" shock pressurization was observed in E-10.
The first pressure rise is
a normal one created by an incident shock front,
whereas the second pressure rise is
taken place by some large disturbance in the main
flow. The reason for this is not
certain yet, but is speculated to be a long relaxation
time or inefficient compressibility
of the fluid. The visualized shock front and its
vicinity of E-10 is completely
different from those of normal gases.
Received May 31, 1994 / Accepted
April 20, 1995 相似文献
15.
L. van Wijngaarden 《Applied Scientific Research》1970,22(1):366-381
Asbtract The structure of shock waves in liquids containing gas bubbles is investigated theoretically. The mechanisms taken into account
are the steepening of compression waves in the mixture by convection and the effects due to the motion of the bubbles with
respect to the surrounding fluid. This relative motion, radial and translational, gives rise to dissipation and to dispersion
caused by the inertia of the radial flow associated with an expanding or compressed bubble. For not too thick shocks the dissipation
by radial motion around the bubbles dominates over the dissipation by relative translational motion, in mixtures with low
gas content. The overall thickness of the shock appears to be determined by the dispersion effect. Dissipation, however, is
necessary to permit a steady shock wave. It is shown that, analogous to undular bores, a stationary wave train may exist behind
the shock wave. 相似文献
16.
The nonlinear problem of the thermal, mass, and dynamic interaction of a single vapor bubble with the surrounding liquid is discussed. This problem has ramifications in research on flows of vapor-liquid mixtures with a bubble-matrix structure, in particular, the propagation of shock waves in such media. Results are given from a numerical solution of the problem of the radial motion imparted to a bubble by a sudden change of pressure in the liquid; this problem corresponds, in particular, to the behavior of bubbles behind a shock front when the latter enters a bubble curtain. 相似文献
17.
S. V. Khabirov 《Journal of Applied Mechanics and Technical Physics》2016,57(6):989-996
The problem of gas pressure equalization in a porous medium filling a pipe with a closed end under shock loading is solved. In this case, the initial filtration velocity behind the shock wave should be specified as initial data, in addition to the shock pressure. It is shown that the shock decays at a finite distance and pressure equalization occurs in a finite time. Approximate submodels of discontinuous and smooth solutions are obtained. 相似文献
18.
Yasuo Mori Kunio Hijikata Atsutomo Komine 《International Journal of Multiphase Flow》1975,2(2):139-152
We deal with a pressure wave of finite amplitude propagating in a gas and liquid medium or in the fluid in an elastic tube. We study the effects of pipe elasticity on the propagation velocity of the pressure wave. Pressure waves of finite amplitude progressing in the two-phase flow are treated considering the void fraction change due to pressure rise. The propagation velocity of the two-phase shock wave is also investigated, and the behavior of the reflection of the pressure wave at the rigid wall is analyzed and compared to that in a pure gas or liquid. The results are compared to experimental data of a pressure wave propagating in the two-phase flow in a vertical shock tube. 相似文献
19.
The present work deals with the numerical investigation of a collapsing bubble in a liquid–gas fluid, which is modeled as a single compressible medium. The medium is characterized by the stiffened gas law using different material parameters for the two phases. For the discretization of the stiffened gas model, the approach of Saurel and Abgrall is employed where the flow equations, here the Euler equations, for the conserved quantities are approximated by a finite volume scheme, and an upwind discretization is used for the non‐conservative transport equations of the pressure law coefficients. The original first‐order discretization is extended to higher order applying second‐order ENO reconstruction to the primitive variables. The derivation of the non‐conservative upwind discretization for the phase indicator, here the gas fraction, is presented for arbitrary unstructured grids. The efficiency of the numerical scheme is significantly improved by employing local grid adaptation. For this purpose, multiscale‐based grid adaptation is used in combination with a multilevel time stepping strategy to avoid small time steps for coarse cells. The resulting numerical scheme is then applied to the numerical investigation of the 2‐D axisymmetric collapse of a gas bubble in a free flow field and near to a rigid wall. The numerical investigation predicts physical features such as bubble collapse, bubble splitting and the formation of a liquid jet that can be observed in experiments with laser‐induced cavitation bubbles. Opposite to the experiments, the computations reveal insight to the state inside the bubble clearly indicating that these features are caused by the acceleration of the gas due to shock wave focusing and reflection as well as wave interaction processes. While incompressible models have been used to provide useful predictions on the change of the bubble shape of a collapsing bubble near a solid boundary, we wish to study the effects of shock wave emissions into the ambient liquid on the bubble collapse, a phenomenon that may not be captured using an incompressible fluid model. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
20.
Fluid-solid coupling typically plays a negligible role in confined converging shocks in gases because of the rigidity of the
surrounding material and large acoustic impedance mismatch of wave propagation between it and the gas. However, this is not
true for converging shocks in a liquid. In the latter case, the coupling can not be ignored and properties of the surrounding
material have a direct influence on wave propagation. In shock focusing in water confined in a solid convergent geometry,
the shock in the liquid transmits to the solid and both transverse and longitudinal waves propagate in the solid. Shock focusing
in water for three types of confinement materials has been studied experimentally with schlieren and photoelasticity optical
techniques. A projectile from a gas gun impacts a liquid contained in a solid convergent geometry. The impact produces a shock
wave in water that develops even higher pressure when focused in the vicinity of the apex. Depending on the confining material,
the shock speed in the water can be slower, faster, or in between wave speeds in the solid. For solid materials with higher
wave speeds than the shock in water, regions in the water is put in tension and cavitation occurs. Materials with slower wave
speeds will deform easily. 相似文献