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1.
V. A. Annenkov V. A. Levin E. V. Trifonov 《Journal of Applied Mechanics and Technical Physics》2006,47(2):153-156
Numerical analysis is performed of the interaction of a shock wave with a local energy source and the wake behind it. It is
shown that for specified shock-wave intensity and flow parameters there is a threshold value of the energy release starting
with which the shock wave collapses.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 2, pp. 3–7, March–April, 2006. 相似文献
2.
Several types of plane shock-wave interactions [1–5], realized in various cases of practical importance, are now known. In
[7] the possibility of the existence of a new type of shock-wave interaction was demonstrated by numerically solving the axisymmetric
boundary-value problem. Here, the corresponding two-dimensional boundary-value problem of the interaction between a shock
wave and a plane shock is numerically studied, a theoretical basis is obtained for the region of existence of the shock-wave
interaction detected, and its principal properties are investigated.
Moscow, Dnepropetovsk. Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 181–183, September–October,
1988. 相似文献
3.
A. V. Pinaev V. T. Kuzavov V. K. Kedrinskii 《Journal of Applied Mechanics and Technical Physics》2000,41(5):836-844
Profiles and values of pressure in shock waves are determined for the case of spherical, linear, and spatial charges, such
as a coil of a bulk spiral and plane annular coils and Archimedes’ spiral of various lenths, exploded in air. In the case
of explosion of rings and spirals, a complex wave structure in the form of a sequence of several shock waves is registered
near the charges along the spiral axes; a weaker attenuation of shock waves with distance and pressure amplitudes two to three
times higher than in the case of a spherical charge of the same mass are observed. It was found that an increase in the length
of a plane spiral does not lead to an increase in the maximum pressure in the shock wave at distances of the order of several
pitches of the spiral from its plane. With distance from spatial charges of different shape but identical mass, the pressure
values in the shock-wave fronts coincide and tend asymptotically to the parameters of a spherical explosion with a significant
increase in the duration of a wave packet generated by the spatial charge. Dependences for evaluation of shock-wave pressure
amplitudes in the near zone of the explosion are presented.
Lavrent’ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 5, pp. 81–90, September–October, 2000. 相似文献
4.
I. R. Smirnovskii 《Journal of Applied Mechanics and Technical Physics》1998,39(3):335-341
The shock-wave structure in an isotropic plasma is studied in the scale of the Debye shielding radius. The boundary condition
at “infinity” is due to the dissipation mechanism of ions reflected from the ion wavefront. The case of the absence of dissipation
corresponds to a collisionless shock wave. It is known that there is a critical Mach number above which the laminar shock
wave is impossible. In addition, two types of boundary conditions which occur if collisions in an equilibrium high- and low-ionized
plasma are taken into account are considered. The reflected ions are assumed to be scattered by electrons in the first case,
and the momentum of the reflected ions is assumed to be transferred to uncharged particles in the second case. The critical
Mach number of a shock wave does not exist under the conditions of collision dissipation of a flux of reflected ions.
St. Petersburg State University, St. Petersburg 198904. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol.
39, No. 3, pp. 14–21, May–June, 1998. 相似文献
5.
N. I. Gvozdovskaya A. G. Kulikovskii 《Journal of Applied Mechanics and Technical Physics》1999,40(2):341-346
We consider the structure of small-amplitude quasitransverse shock waves in a weakly anisotropic elastic medium which possesses
an internal structure generating the wave dispersion. The dispersion is modeled by introducing terms with higher derivatives
into the equations of the theory of elasticity, and the dissipation is represented by viscous terms. In one of the two possible
cases treated below, the requirement that the discontinuity structure exist leads to a set of admissible discontinuities of
complex structure. A considerable part of the shock adiabat consists of a set of short portions and separate points, the number
of which increases as the viscosity decreases. This complex set of admissible discontinuities is the general case where the
dispersion in the shock-wave structure is sufficiently strong.
Steklov Institute of Mathematics, Russian Academy of Sciences, Moscow 117526. Translated from Prikladnaya Mekhanika i Tekhnicheskaya
Fizika, Vol. 40, No. 2, pp. 174–180, March–April, 1999. 相似文献
6.
The problem of shock-wave compaction of a metal powder enclosed in a metal container with a transverse partition is solved.
A model of wave formation on the partition and in the compact adjacent to the partition is proposed; the model is based on
the loss of strength in the powder due to collapsing of pores and to development of instability of the partition being compressed
in the shock wave.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 1, pp. 119–130, January–February, 2006. 相似文献
7.
N. A. Stebnovskii 《Journal of Applied Mechanics and Technical Physics》2000,41(2):251-260
The conditions of development of bubble cavitation in liquid media upon shock-wave loading are found. It is s shown that,
for the development of an unbounded cavitation, the bubbles should grow to certain critical sizes sufficient for their transition
to a nonequilibrium state owing to the elastic energy transferred by a rarefaction wave to a liquid sample (at the stage of
unloading). In contrast to low-viscosity liquids, in high-viscosity ones (such as glycerin) these conditions cannot be satisfied
for any really attainable parameters of shock waves.
Lavrent'ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 2, pp. 53–63, March–April, 2000. 相似文献
8.
A method of theoretical investigation of the flow field in a two-dimensional (plane-parallel or axisymmetric) overexpanded
jet of an ideal perfect gas in the vicinity of the nozzle lip is described. The changes in curvature of the shock wave emanating
from the lip, as well as the shock-wave intensity and flow parameters behind the shock are analyzed as functions of the Mach
number, pressure ratio in the plane jet, and ratio of specific heats of the gas.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 3, pp. 72–83, May–June, 2006. 相似文献
9.
The problem of the shock-wave structure in a mixture of two compressible media with different velocities and pressures of
components is considered. The problem is reduced to solving a boundary-value problem for two ordinary differential equations
that describe the velocity relaxation and pressure equalization of the components. Using methods of the qualitative theory
of dynamic systems on a plane, the existence and uniqueness of four types of waves are shown: (a) fully dispersed waves; (b) frozen-dispersed waves; (c) dispersed-frozen waves; (d) frozen waves of two-front configuration. A chart of solutions of the corresponding flow types is constructed in the plane
of the following parameters: the initial velocity of the mixture and the initial volume concentration of one of the components.
The numerical calculations conducted illustrate the obtained analytical structures of the shock wave. It is shown that the
results obtained using the suggested mathematical model are in agreement with experimental data on the dependence of the velocity
of the dispersed shock wave on the equilibrium pressure behind the shock-wave front for a mixture of silica sand and water.
Institute of Theoretical and Applied Mechanics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated
from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 39, No. 2, pp. 10–19, March–April, 1998. 相似文献
10.
V. Ya. Ternovoi K. V. Khishchenko A. A. Charakhch’yan 《Journal of Applied Mechanics and Technical Physics》2009,50(3):371-379
This paper considers the interaction between an absolutely rigid wall or a steel plate and the rarefaction wave arising in
solid deuterium when a 30–150 GPa shock wave arrives at the free surface. It is shown that, in the entropy trace near the wall or interface with the plate,
a high-temperature plasma arises, in which a thermonuclear fusion is possible, at least, for shock-wave pressures above 70 GPa. The dimension of the plasma region and the time of its establishment are proportional to the distance between the free surface
and the wall. Estimates of the proportionality coefficients are given. It is noted that, in this case, unlike in other methods
of high-temperature plasma generation, the time of existence of the plasma may not depend on the sound velocity in it. It
is shown that, by using a conical solid-state target wit an exit hole, the shock-wave pressure in solid deuterium can be increased
from 10 to 100 GPa.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 3, pp. 15–24, May–June, 2009. 相似文献
11.
I. A. Bedarev Yu. A. Gosteev A. V. Fedorov 《Journal of Applied Mechanics and Technical Physics》2007,48(1):17-26
The dynamics of particles of the disperse phase in a turbulent gas flow in planar shock waves sliding along a solid surface
with a trapezoid cavity is examined numerically. Lifting of particles from the cavity walls is calculated in the approximation
of a rarefied gas suspension. It is shown that the intensity of the transient shock wave and the initial positions of particles
have a significant effect on the particle-lifting properties. The height of particle lifting is found to nonmonotonically
depend on the initial streamwise coordinate and shock-wave Mach number. It is shown that zones of aggregation and subtraction
of particles may be formed at the cavity bottom.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 1, pp. 24–34, January–February, 2007. 相似文献
12.
We calculate the quasi-stationary structure of a radiating shock wave propagating through a spherically symmetric shell of
cold gas by solving the time-dependent equations of radiation hydrodynamics on an implicit adaptive grid. We show that this
code successfully resolves the shock wave in both the subcritical and supercritical cases and, for the first time, we have
reproduced all the expected features – including the optically thin temperature spike at a supercritical shock front – without
invoking analytic jump conditions at the discontinuity. We solve the full moment equations for the radiation flux and energy
density, but the shock wave structure can also be reproduced if the radiation flux is assumed to be proportional to the gradient
of the energy density (the diffusion approximation), as long as the radiation energy density is determined by the appropriate
radiative transfer moment equation. We find that Zel'dovich and Raizer's (1967) analytic solution for the shock wave structure
accurately describes a subcritical shock but it underestimates the gas temperature, pressure, and the radiation flux in the
gas ahead of a supercritical shock. We argue that this discrepancy is a consequence of neglecting terms which are second order
in the minimum inverse shock compression ratio [, where is the adiabatic index] and the inaccurate treatment of radiative transfer near the discontinuity. In addition, we verify
that the maximum temperature of the gas immediately behind the shock is given by , where is the gas temperature far behind the shock.
Received 21 September 1998/ Accepted 2 February 1999 相似文献
13.
J. -Ph. Boin J. Ch. Robinet Ch. Corre H. Deniau 《Theoretical and Computational Fluid Dynamics》2006,20(3):163-180
The principal objective of this paper is to study some unsteady characteristics of an interaction between an incident oblique shock wave impinging a laminar boundary layer developing on a plate plane. More precisely, this paper shows that some unsteadiness, in particular the low frequency unsteadiness, originate in a supercritical Hopf bifurcation related to the dynamics of the separated boundary layer and not necessarily to the coherent structures resulting from the turbulent character of the boundary layer crossing the shock wave. Numerical computations of a shock-wave/laminar boundary-layer interaction (SWBLI) have been compared with a classical test case (Degrez test case) and both two-dimensional and three-dimensional (3D) unsteady Navier–Stokes equations are numerically solved with an implicit dual time stepping for the temporal algorithm and high order AUSM+ scheme for the spatial discretization. A parametric study on the oblique shock-wave angle has been performed to characterize the unsteady behaviour onset. Finally, discussions and assumptions are made about the origin of the 3D low frequency unsteadiness. 相似文献
14.
V. K. Kedrinskii 《Journal of Applied Mechanics and Technical Physics》2007,48(3):340-345
An equation is proposed for the pulsation of a single cavity in an abnormally compressible bubbly liquid which is in pressure
equilibrium and whose state is described by the Lyakhov equation. In the equilibrium case, this equation is significantly
simplified. Numerical analysis is performed of the bubble dynamics and acoustic losses (the profile and amplitude of the radiation
wave generated on the bubble wall from the side of the liquid). It is shown that as the volumetric gas concentration k0 in the equilibrium bubbly medium increases, the degree of compression of the cavity by stationary shock wave decreases and
its pulsations decrease considerably and disappear already at k0 = 3%. In the compression process, the cavity asymptotically reaches an equilibrium state that does not depend on the value
of k0 and is determined only by the shock-wave amplitude. The radiation wave takes the shape of a soliton whose amplitude is much
smaller and whose width is considerably greater than the corresponding parameters in a single-phase liquid.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 3, pp. 51–57, May–June, 2007. 相似文献
15.
Results from an experimental investigation of the interaction of a “non-ideal” shock wave and a single obstacle are reported. The shock wave is produced ahead of an accelerated flame in a 14 cm inner-diameter tube partially filled with orifice plates. The shock wave interacts with a single larger blockage orifice plate placed 15–45 cm after the last orifice plate in the flame acceleration section of the tube. Experiments were performed with stoichiometric ethylene–oxygen mixtures with varying amounts of nitrogen dilution at atmospheric pressure and temperature. The critical nitrogen dilution was found for detonation initiation. It is shown that detonation initiation occurs if the chemical induction time based on the reflected shock state is shorter than the time required for an acoustic wave to traverse the orifice plate upstream surface, from the inner to the outer diameter. The similarity between the present results and those obtained from previous investigators looking at detonation initiation by ideal shock reflection produced in a shock tube indicates that the phenomenon is not sensitive to the detailed structure of the shock front but only on the average shock strength.This paper is based on work that was presented at the 20th International Colloquium on the Dynamics of Explosions and Reactive Systems, Montreal, Canada, July 31–August 5, 2005. 相似文献
16.
S. M. Aulchenko V. P. Zamuraev A. P. Kalinina 《Journal of Applied Mechanics and Technical Physics》2011,52(5):748-754
Interaction of a pulsed periodic source of energy with a closing shock wave arising near airfoils in transonic flight is studied.
The evolution of the shock-wave structure of the flow around a symmetric airfoil is examined by solving two-dimensional unsteady
gas-dynamic equations, and a resonant mechanism of interaction is found, which leads to considerable (by an order of magnitude)
reduction of the wave drag of the airfoil. 相似文献
17.
S. M. Aulchenko V. P. Zamuraev A. P. Kalinina 《Journal of Applied Mechanics and Technical Physics》2006,47(3):359-365
Changes in the structure of a transonic flow around a symmetric airfoil and a decrease in the wave drag of the latter, depending
on the energy-supply period and on localization and shape of the energy-supply zone, are considered by means of the numerical
solution of two-dimensional unsteady equations of gas dynamics. Energy addition to the gas ahead of the closing shock wave
in an immediate vicinity of the contour in zones extended along the contour is found to significantly reduce the wave drag
of the airfoil. The nature of this decrease in drag is clarified. The existence of a limiting frequency of energy supply is
found.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 3, pp. 64–71, May–June, 2006. 相似文献
18.
Triple shock-wave configurations in steady supersonic flows of an inviscid perfect gas are considered. Triple configurations
with special intensities of shock waves and extreme ratios of various flow parameters behind these configurations are determined.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 4, pp. 39–53, July–August, 2006. 相似文献
19.
H.G. Hornung 《Shock Waves》1998,8(1):11-21
The inviscid equations of motion for the flow at the downstream side of a curved shock are solved for the shock–normal derivatives.
Combining them with the shock–parallel derivatives yields gradients and substantial derivatives. In general these consist
of two terms, one proportional to the rate of removal of specific enthalpy by the reaction, and one proportional to the shock
curvature. Results about the streamline curvature show that, for sufficiently fast exothermic reaction, no Crocco point exists.
This leads to a stability argument for sinusoidally perturbed normal shocks that relates to the formation of the structure
of a detonation wave. Application to the deflection–pressure map of a streamline emerging from a triple shock point leads
to the conclusion that, for non–reacting flow, the curvature of the Mach stem and reflected shock must be zero at the triple
point, if the incident shock is straight. The direction and magnitude of the gradient at the shock of any flow quantity may
be written down using the results. The sonic line slope in reacting flow serves as an example. Extension of the results –
derived in the first place for plane flow – to three dimensions is straightforward.
Received 12 February 1997 / Accepted 10 June 1997 相似文献
20.
Experimental studies were made of the state behind a shock wave arising in front of a pulse jet in formation, and the development
of the vortex structure of the jet itself. A comparison was made of the experimental axial density distribution in the jet
in the region between the front of the gas and the primary shock wave with the solutions to the problem of an expanding spherical
piston and the nonself-similar problem of a point explosion.
Moscow Translated from Izvestiya, Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 146–150, September–October, 1988. 相似文献