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1.
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
2.
The problem of the influence of bracing struts of two types on the aeroelastic stability of a wing is studied. The formulation
of the problem follows that considered by M. V. Keldysh [1]. The behavior of the eigenvalues is studied in the complex plane
and the stability, flutter, and divergence domains are constructed.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 151–162, January–February,
1998. 相似文献
3.
N. V. Chertova 《Journal of Applied Mechanics and Technical Physics》2008,49(6):1047-1054
The propagation of plane harmonic waves in viscoelastic and elastoviscoplastic materials are studied using the equations of
the field theory of defects, the kinematic identities for an elastic continuum with defects, and the dynamic equations of
gauge theory. Wave propagation velocities and refraction and absorption coefficients are determined. The structure of the
waves and the correlation between the displacement waves and the defect-field waves determining plastic deformation are analyzed.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 6, pp. 190–197, November–December, 2008. 相似文献
4.
V. V. Zozulya 《International Applied Mechanics》2007,43(5):586-590
The contact-interaction problem for a stationary plane crack with friction between its edges under the action of a normal
(to the crack plane) harmonic shear wave is addressed. Antiplane deformation conditions are considered. The distribution of
contact forces and displacement discontinuity of crack edges are studied
Published in Prikladnaya Mekhanika, Vol. 43, No. 5, pp. 138–142, May 2007. 相似文献
5.
Yu. A. Berezin L. A. Spodareva 《Journal of Applied Mechanics and Technical Physics》2000,41(3):456-460
The stability of a layer of a viscoelastic liquid on an inclined plane is studied within the framework of the model with a
time-dependent “memory” in the presence of surface tension. It is shown analytically and numerically that these flows can
be stable or unstable depending on the Reynolds number. Profiles of the free surface are found as functions of the Reynolds
and Weber numbers.
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 3, pp. 86–91, May–June, 2000. 相似文献
6.
I. I. Ryzhkov 《Journal of Applied Mechanics and Technical Physics》2006,47(1):79-90
The group properties of the thermal-diffusion equations for a binary mixture in plane flow are studied. Optimal systems of
first-and second-order subalgebras are constructed for the admissible Lie operator algebra, which is infinite-dimensional.
Examples of the exact invariant solutions are given, which are found by solving ordinary differential equations. Exact solutions
are found that describe thermal diffusion in an inclined layer with a free boundary and in a vertical layer in the presence
of longitudinal temperature and concentration gradients. The effect of the thermal-diffusion parameter on the flow regime
is studied.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 1, pp. 95–108, January–February, 2006. 相似文献
7.
The thickness vibrations of elastic inhomogeneous bodies of different geometry under dynamic harmonic loading are studied.
The dependence of the amplitude–frequency characteristics of homogeneous and inhomogeneous bodies on excitation frequency
is analyzed in detail. The frequency spectra for plane, cylindrical, and spherical layers are determined 相似文献
8.
The flow-induced microstructure of a mesophase pitch was studied within custom-made dies for changing wall shear rates from
20 to 1,100 s − 1, a flow scenario that is typically encountered during fiber spinning. The apparent viscosity values, measured at the nominal
wall shear rates ranging from 500 to 2,500 s − 1 using these dies, remain fairly constant. The microstructure was studied in two orthogonal sections: r–θ (cross section) and r–z (longitudinal mid plane). In these dies, the size of the microstructure gradually decreases toward the wall (to as low as
a few micrometers), where shear rate is highest. Furthermore, as observed in the r–θ plane of the capillary, for a significant fraction of the cross section, discotic mesophase has a radial orientation. Thus,
the directors of disc-like molecules were aligned in the vorticity (θ) direction. As confirmed from the microstructure in the r–z plane, most of the discotic molecules remain nominally in the flow plane. Orientation of the pitch molecules in the shear
flow conditions is consistent with that observed in controlled low-shear rheometric experiments reported earlier. Microstructral
investigation suggests that the radial orientation of carbon fibers obtained from a mesophase pitch originates during flow
of pitch through the die. 相似文献
9.
The convective instability of mechanical equilibrium of an inclined plane layer of fluid developing under the action of a
static gravity field and high-frequency vibration is studied. Configurations corresponding to four directions of the equilibrium
temperature gradient — vertical, longitudinal, horizontal, and transverse — are considered for an arbitrary orientation of
the vibration axis. The stability limits and the characteristics of the critical perturbations are determined.
Perm’. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 8–15, January–February,
1998.
This investigation was carried out with partial support form RSA-NASA (contract No. 920/18 — 5208/96). 相似文献
10.
V. A. Bykov E. F. Gryaznov V. N. Okhitin 《Journal of Applied Mechanics and Technical Physics》2009,50(3):406-412
The process of projection of a layer of an ideal liquid enclosed into a cylindrical elastoplastic shell by products of instantaneous
detonation of a high explosive charge is studied numerically in a two-dimensional plane formulation. The processes of shell
fracture and liquid exhaustion through the resultant slots are considered. Numerical results are analyzed, and analytical
relations for angular distributions of radial velocity and mass of the liquid escaping through the slots are derived.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 3, pp. 56–63, May–June, 2009. 相似文献
11.
The crosslinking of the unsaturated polyester was studied by using experiments and a model of the process. The kinetic parameters
were calculated from the heat flux–time curves obtained by differential scanning calorimetry (DSC, Netzsch–Simultaneous Thermal
Analyser DSC 200), working in DSC (dynamic) mode. The temperature–time histories were studied in plain sheet copper mould.
The mathematical model was constructed by taking into account the heat transferred by conduction through the resin, as well
as the kinetics of heat generated by the crosslinking reaction. The contributions to the rise in temperature from heat conduction
and chemical reaction are different in different parts of the composite, and can explain the temperature-, or degree of crosslinking
(DOC)–time histories. By considering temperature–time histories developed within the sample, more extensive knowledge of the
process can be obtained. The effect of the heat transfer by conduction through the composite as well as the internal heat
generated by the cure reaction is clearly shown, despite the complexity of the process. Finally, good agreement between experimental
data and predicted mathematical model of the crosslinking process in plane sheet mould was shown. 相似文献
12.
V. D. Bondar’ 《Journal of Applied Mechanics and Technical Physics》2009,50(2):352-359
The plane strain of an incompressible body is studied with geometrical and physical nonlinearity and potential forces taken
into account. A nonlinear system of equations for strains is obtained in actual variables, and conditions of its ellipticity
are derived in terms of the elastic potential. Boundary conditions for strains are found from specified loads. Analytical
solutions of the boundary problem in strains and their corresponding stress fields are found for the case of identical elongations.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 2, pp. 217–225, March–April, 2009 相似文献
13.
V. D. Bondar' 《Journal of Applied Mechanics and Technical Physics》2000,41(3):547-555
The averaged rotations and other mechanical parameters at finite plane strains of an elastic material, which are characterized
by a linear relation between the Cauchy stresses and the Almansi strains, are studied. The form of the elastic potential is
determined. The displacement problem is reduced to a boundary-value problem for complex potentials, which is solved in terms
of Cauchy-type integrals for the specified boundarys displacements. The results obtained are compared with the linear solution.
Novosibirsk State University, Novosibirsk 630090. Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41,
No. 3, pp. 187–196, May–June, 2000. 相似文献
14.
A. Ya. Grigorenko I. I. Dyyak I. I. Prokopyshin 《International Applied Mechanics》2008,44(11):1213-1222
To solve two-dimensional boundary-value problems of elasticity, two iteration algorithms of the domain decomposition method
are proposed: parallel Neumann–Neumann and sequential Dirichlet–Neumann. They are based on the hybrid boundary–finite-element
approximations. The algorithms are proved to converge. The optimal parameters are selected using the minimum-residual and
steepest-descent methods. Some plane problems of elasticity are solved as examples, and stationary and nonstationary iteration
algorithms in these examples are analyzed for efficiency
Translated from Prikladnaya Mekhanika, Vol. 44, No. 11, pp. 18–29, November 2008. 相似文献
15.
J. J. Rushchitsky 《International Applied Mechanics》2005,41(11):1288-1298
General principles are formulated for modeling the elastic deformation of materials and analyzing plane waves in nonlinearly
elastic materials such as hyperelastic, hypoelastic, and those governed by the general law of elasticity. The results of studying
the propagation of plane waves in hypoelastic materials are further outlined. The influence of initial stresses and initial
velocities on the types and number of plane waves is studied. Wave effects characteristic of hypoelastic materials are predicted
theoretically. One of such effects is blocking of certain types of plane waves by initial stresses
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Translated from Prikladnaya Mekhanika, Vol. 41, No. 11, pp. 96–107, November 2005. 相似文献
16.
A comparative analysis of two types of hyperelastic waves—plane waves (with plane front) and cylindrical waves (with curved
front)—is offered. The propagation of the waves is studied theoretically for quadratically nonlinear hyperelastic media and
numerically for a class of unidirectional fibrous composite materials. Hyperelasticity is described using the classical Murnaghan
potential and a structural model of the first order—the model of effective constants. The internal structure of materials
is described by this model and is at the micro-or nanolevels in numerical analysis. Particular attention is given to the evolution
of the wave profile. It is studied in three stages: (i) derivation of nonlinear wave equations, (ii) construction of solutions
in the form of plane and cylindrical waves, and (iii) numerical analysis of the evolution of these waves in composites with
microlevel (Thornel) or nanolevel (Z-CNT) fibers. The main similarities and differences between plane longitudinal and cylindrical
waves are shown. The most unexpected result is the striking difference between the evolution patterns numerically observed
for plane and cylindrical wave profiles
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Translated from Prikladnaya Mekhanika, Vol. 42, No. 10, pp. 21–46, October 2006. 相似文献
17.
The wave instability of convective boundary layers in a horizontal cylindrical layer of ethanol under the action of vertical
hamonic high-frequency vibration is studied. A strong destabilizing effect of the vibration on the stability of the convective
boundary layers is detected. In the plane of the gravity and vibration Rayleigh numbers (Ra and R
V
), the excitation limit of the wave instability is determined. The periods of the temperature oscillations caused by the waves
in the boundary layers near the inner and outer cavity boundaries are studied as functions of the Rayleigh numbers.
Perm’. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 3, pp. 32–40, May–June, 1998. 相似文献
18.
A. N. Prokunin 《Fluid Dynamics》1998,33(4):573-579
At small Reynolds numbers, the gravity-driven motion of a solid spherical particle along an inclined plane in a Newtonian
liquid initially at rest was studied experimentally. A comparison of the experiment with the calculations showed that motions
both with and without particle-plane contact may occur. The latter cannot be explained within the Stokes approximation.
Moscow. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 4, pp. 129–136, July–August, 1998. 相似文献
19.
Thin elastic panels subjected to compression in the median plane and to supersonic gas flow are considered. An element is
attached to the panel by an elastic spring and linear dashpot. The stability of the initial planar state of the panel is studied
as a function of the main control parameters—such as the gas velocity and membrane force—and the parameters of the attached
element. The evolution of the stability regions in the control-parameter plane is considered. Special attention is paid to
compound bifurcation points and stabilization islets.
Institute of Machine Science, Russian Academy of Sciences, Moscow, Russia. Translated from Prikladnaya Mekhanika, Vol. 35,
No. 12, pp. 3–10, December, 1999. 相似文献
20.
A. V. Proskurin A. M. Sagalakov 《Journal of Applied Mechanics and Technical Physics》2008,49(3):383-390
The stability of the plane flow of an electrically conducting fluid with respect to small perturbations was studied at large
Reynolds numbers in the presence of a longitudinal magnetic field. The dependence of the critical Reynolds number on the electrical
conductivity is investigated. At large Reynolds numbers, a new branch of instability and a sudden change in the critical Reynolds
numbers is found.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 3, pp. 45–53, May–June, 2008. 相似文献