共查询到20条相似文献,搜索用时 31 毫秒
1.
M. I. Muchnaya 《Fluid Dynamics》1999,34(1):136-138
The direct problem of viscous gas flow in a hypersonic nozzle of given geometry is solved on the basis of simplified Navier-Stokes
equations. At a stagnation pressure of the order of several thousands of atmospheres, a compressibility factor is introduced
into the equation of state. The gasdynamic parameter profiles and the Mach number distribution along the nozzle axis are obtained.
The results of earlier calculations of profiled nozzles are revised.
Novosibirsk. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 161–164, January–February,
1999. 相似文献
2.
A. V. Kazakov 《Fluid Dynamics》1998,33(6):850-855
The results of a numerical investigation of the effect of thermal energy supply on a swirling viscous heat-conducting gas
flow in a subsonic cocurrent stream are presented. The initial stage of development of the swirling flow in the neighborhood
of the vortex axis with constant circulation in the outer flow region is considered for two different distributions of the
streamwise velocity vector component which simulate a swirling jet-type flow and a wake flow with a streamwise velocity deficit.
The effect of local volume energy supply in the neighborhood of the vortex axis, the circulation of the azimuthal velocity
component, and the longitudinal pressure gradient in the inviscid stream on the development of the swirling flow and the process
of breakdown of cocurrent vortex flows is investigated.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 6, pp. 47–53, November–December,
1998.
The work was carried out with financial support from the Russian Foundation for Basic Research (project No. 96-01-00586). 相似文献
3.
V. V. Fedorenko 《Nonlinear Oscillations》2009,12(1):133-136
We consider dynamical systems defined by continuous maps of an interval I of the real axis into itself. We prove that if an interval J in I contains the preimage of a periodic point of period p of a map f ∈ C
0(I, I), then the sequence of intervals f
2pn
(J), n= 0, 1, 2,…, is convergent.
Translated from Neliniini Kolyvannya, Vol. 12, No. 1, pp. 130–133, January–March, 2009. 相似文献
4.
S. V. Khabirov 《Journal of Applied Mechanics and Technical Physics》1998,39(6):850-857
An invariant submodel of the equations of gas dynamics constructed on a one-dimensional subalgebra consisting of the sum of
operators of rotation and translation in time is studied within the framework of the SUBMODELS program. The system of equations
of the submodel is brought to symmetric form. Hyperbolicity conditions for the system are derived. Group analysis is performed
and an invariant solution is considered. Isobaric flows are listed. For the simplest of them, characteristics and strong discontinuities
are considered. Necessary conditions for existence of solutions without singularities on the axis are derived.
Institute of Mechanics, Ural Scientific Center, Russian Academy of Sciences, Ufa 450000. Translated from Prikladnya Mekhanika
i Tekhnicheskaya Fizika, Vol. 39, No. 6, pp. 37–45, November–December, 1998. 相似文献
5.
6.
T. V. Bazhenova S. B. Bazarov T. A. Bormotova V. V. Golub A. M. Shulmeister 《Fluid Dynamics》1998,33(2):190-195
The nonstationary interaction between a supersonic pulse jet and a flat plate perpendicular to the jet axis is studied experimentally
and numerically. The time dependences of the pressure and heat flux at various points on the obstacle and the spatial distribution
of the density are obtained experimentally. The nonstationary flow is calculated numerically by the Godunov method. The experiments
and calculations reveal the effect of the reflected starting shock wave and the front part of the swirled gas outflow on the
distribution of the dynamic and thermal loads acting on the plate, in both time and space.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 2, pp. 45–51, March–April, 1998.
This research was carried out with partial financial support from the Russian Foundation for Fundamental Research (project
No. 96-02-16170). 相似文献
7.
The high-speed combustible gas ignited by a hot gas jet, which is induced by shock focusing, was experimentally investigated. By use of the separation mode of shock tube, the test section of a single shock tube is split into two parts, which provide the high-speed flow of combustible gas and pilot flame of hot gas jet, respectively. In the interface of two parts of test sections the flame of jet was formed and spread to the high-speed combustible gas. Two kinds of the ignitions, 3-D “line-flame ignition” and 2-D “plane-flame ignition”, were investigated. In the condition of 3-D “line-flame ignition” of combustion, thicker hot gas jet than pure air jet, was observed in schlieren photos. In the condition of 2-D “plane-flame ignition” of combustion, the delay time of ignition and the angle of flame front in schlieren photos were measured, from which the velocity of flame propagation in the high-speed combustible gas is estimated in the range of 30–90m/s and the delay time of ignition is estimated in the range of 0.12–0.29ms.
PACS 47.40.Nm; 82.40.FpPart of this paper was presented at the 5th International Workshop on Shock/Vortex Interaction, Kaohsiung, October 27–31, 2003. 相似文献
8.
Rebounding of a shaped-charge jet 总被引:1,自引:0,他引:1
E. V. Proskuryakov M. V. Sorokin V. M. Fomin 《Journal of Applied Mechanics and Technical Physics》2007,48(5):633-635
The phenomenon of rebounding of a shaped-charge jet from the armour surface with small angles between the jet axis and the
target surface is considered. Rebounding angles as a function of jet velocity are obtained in experiments for a copper shaped-charge
jet. An engineering calculation technique is developed. The results calculated with the use of this technique are in reasonable
agreement with experimental data.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 5, pp. 17–20, September–October, 2007. 相似文献
9.
A. S. Chuiko 《Nonlinear Oscillations》2005,8(2):277-287
We obtain estimates for the values of a small parameter for which the iteration procedure used for the construction of solutions
of the Noetherian weakly nonlinear boundary-value problem for a system of ordinary differential equations is convergent in
both critical and noncritical cases.
__________
Translated from Neliniini Kolyvannya, Vol. 8, No. 2, pp. 278–288, April–June, 2005. 相似文献
10.
We study a rapidly convergent modification of a two-sided method for the approximate integration of a boundary-value problem
with parameters in boundary conditions for a system of quasilinear second-order differential equations.
__________
Translated from Neliniini Kolyvannya, Vol. 11, No. 3, pp. 348–364, July–September, 2008. 相似文献
11.
The stability of an axisymmetric flow of viscous gas in a circular pipe, which models the Burgers vortex in the pipe axis
neighborhood, is studied within the linear theory framework. Neutral curves for the most unstable disturbances are calculated.
The influence of the characteristic Mach number on the flow stability is investigated. It is shown that for a given model
velocity distribution the Mach number affects only the temperature and pressure profiles of the main undisturbed flow. In
this case, for the disturbance types considered, as the Mach number increases, the critical Reynolds number corresponding
to loss of stability decreases.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 35–41, January–February,
1999.
The work received financial support from the Russian Foundation for Basic Research (project No. 96-01-00586). 相似文献
12.
We consider a weakly nonlinear boundary-value problem for a system of second-order ordinary differential equations. We find
a sufficient condition for the existence of at least one solution of this problem and propose a convergent iterative algorithm
for the determination of its solution.
__________
Translated from Neliniini Kolyvannya, Vol. 9, No. 3, pp. 368–375, July–September, 2006. 相似文献
13.
A fluorescence image analysis procedure to determine the distribution of species concentration and density in a gas flow is
proposed. The fluorescent emission is due to the excitation of atoms/molecules of a gas that is intercepted by an electron
sheet. The intensity of the fluorescent light is proportional to the local number density of the gas. When the gas flow is
a mixture of different species, this proportionality can be used to extract the contribution associated with the species from
the spectral superposition acquired by a digital camera. In particular, the fact is exploited such that the ratio between
a pair of color intensities takes different values for different gases and that different linear superpositions of different
color intensities yield a ratio that varies with the species concentration. This leads to a method that simultaneously reveals
species concentrations and mass density of the mixture. For the proper working of a continuous electron gun in a gas, the
procedure can be applied to gas flow where the pressure is below the thresholds of 200∼300 Pa and the number density is no
greater than 1023 m−3. To maintain the constancy of the emission coefficients, the temperature variation in the flow should be inside the range
75–900 K (above the temperature where the probability to meet disequilibrium phenomena due to rarefaction is low, below the
temperature where visible thermal emission is present). The overall accuracy of the measurement method is approximately 10%.
The uncertainty can vary locally in the range from 5 to 15% for the concentration and from 5 to 20% for the density depending
on the local signal-to-noise ratio. The procedure is applied to two under-expanded sonic jets discharged into a different
gas ambient—Helium into Argon and Argon into Helium—to measure the concentration and density distribution along the jet axis
and across it. A comparison with experimental and numerical results obtained by other authors when observing under-expanded
jets at different Mach numbers is made with the density distribution along the axis of the jet. This density distribution
appears to be self-similar. 相似文献
14.
This paper discusses gas-dynamic aspects of intense explosions in uniform environments. In experiments, the energy of a laser
is almost instantaneously released in a volume of air shaped as either a flattened or stretched cylinder generating a blast
wave. Its shape evolves in time and ultimately becomes spherical. But momentum transferred to the air when the blast wave
is strongly nonspherical is anisotropic. As a result, a subsonic jet and a vortex are induced and propagate along the symmetry
axis or along the perpendicular plane, depending on the initial configuration of the blast wave. Simulations based on a free-Lagrangian
method for a nonviscous gas are in good agreement with the experiments. Velocities, circulation, and positions of fluid particles
found in computations give an insight into the causes and details of the flow. Two simultaneous and contrary processes take
place – vorticity production by the anisotropic shock wave and baroclinical generation of vorticity at the boundary of the
heated gas – which give rise to net circulation.
Received 21 April 1997 / Accepted 27 June 1997 相似文献
15.
N. A. Pribaturin D. P. Stasenko 《Journal of Applied Mechanics and Technical Physics》2000,41(2):261-266
The effect of shock waves on gas absorption by liquid in bubbly media with different degrees of gas solubility is studied.
It is shown that a shock wave acting on a gas-liquid medium can significantly enhance the mass transfer between the gas and
the liquid.
Kutateladze Institute of Thermal Physics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 2, pp. 64–70, March–April, 2000. 相似文献
16.
A. N. Golovanov 《Journal of Applied Mechanics and Technical Physics》2006,47(5):637-642
A gas-dynamic flow in an axisymmetric convective jet is studied experimentally. It is demonstrated that the jet flow with
Grashof numbers Gr = (0.4–2.0) · 106 is self-similar. Acoustic oscillations directed perpendicular to the axis of symmetry transform the profiles of the gas-flow
parameters; two temperature maximums located outside the axis can appear. The results obtained indicate that flow instability
is generated in high-gradient regions.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 5, pp. 27–33, September–October, 2006. 相似文献
17.
V. Sh. Shagapov M. K. Khasanov N. G. Musakaev 《Journal of Applied Mechanics and Technical Physics》2008,49(3):462-472
Specific features of formation of gas hydrates due to injection of a gas into a porous medium initially filled by a gas and
water are considered. Self-similar solutions of an axisymmetric problem, which describe the distributions of the basic parameters
in the reservoir, are constructed. The existence of solutions is demonstrated, which predict gas hydrate formation both on
the frontal surface and in the volume zone.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 3, pp. 137–150, May–June, 2008. 相似文献
18.
A. V. Kazakov 《Fluid Dynamics》1998,33(3):338-345
The results of calculating the stability of a three-dimensional swirl flow of a viscous heat-conducting gas are presented.
The stability characteristics are determined using the linear time-dependent theory of plane-parallel flow stability. The
main undisturbed axisymmetric vortex flow was determined numerically using a quasi-cylindrical approximation for the complete
set of Navier-Stokes equations. The circulation of the peripheral velocity in the cocurrent flow surrounding the viscous vortex
core was assumed to be constant. In analyzing the stability, nonaxisymmetric perturbations in the shape of waves traveling
along the vortex axis with both positive and negative wavenumbers were considered; in these two cases the perturbation rotation
is either the same or opposite in sense to the rotation in the vortex core. Neutral stability curves are determined for various
values of the swirling parameter and the cocurrent flow Mach number.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 50–59, May–June, 1998. 相似文献
19.
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
20.
N. V. Gnevanov B. L. Smorodin 《Journal of Applied Mechanics and Technical Physics》2006,47(2):214-220
Stability of a plane-parallel flow of a nonuniformly heated binary mixture filling a vertical layer located in a field of
gravity and in a high-frequency vibrational field is studied. The axis of vibrations is directed along the layer. The case
of rigid and isothermal boundaries of the layer impermeable for the mixture is considered. The influence of thermal diffusion
on the evolution of the admixture and the thresholds of flow stability is taken into account. The study is performed on the
basis of equations for averaged fields. An asymptotic method with the use of the perturbation wavenumber as a small parameter
is applied in the long-wave limit. For arbitrary values of the wavenumber, the limit of stability was determined by numerical
integration. Charts of stability of gaseous and liquid binary mixtures are plotted.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 2, pp. 77–84, March–April, 2006. 相似文献