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1.
An experimental study is made of specific features of the motion of the free surface of liquid in different conical shells,
the formation, motion, and local accumulation of gas bubbles in the shells, and the character of random motion of the gas-liquid
medium in a vibrational force field. It is established that the liquid moves along the horizontal as well as the vertical
axes under certain conditions when axisymmetric modes of vibration of the free surface are excited. The main characteristics
of the dynamic behavior of a gas-liquid medium in a compound conical shell having the form of a de Laval nozzle are examined
for the case when the medium forms a nonlinear oscillatory “liquid-gas” system that is dynamically stable.
S. P. Timoshenko Institute of Mechanics, National Academy of Sciences of Ukraine, Kiev, Ukraine. Translated from Prikladnaya
Mekhanika, Vol. 35, No. 2, pp. 23–29, February, 1999. 相似文献
2.
M. V. Shamolin 《International Applied Mechanics》2007,43(10):1107-1122
The paper addresses the stability of solutions of ordinary differential equations of particular type for different statements
and assumptions. The equations are interpreted as models of motion of a rigid body under the action of the ambient medium
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 10, pp. 49–67, October 2007. 相似文献
3.
Milan Batista 《International Journal of Non》2008,43(1):26-35
The article is devoted to the study of the motion of a rigid body of revolution on a rigid and perfectly smooth horizontal surface under the influence of the uniform gravitational field. Basic equations are listed and their solutions are given. The unilateral contact between the body and the plane at non-steady motion is investigated and the procedure of calculation of threshold values of the body energy above which the contact is broken is given. In contrast to Shimomura et al. [Dynamics of an axisymmetric body spinning on a horizontal surface. II. Self-induced jumping. Proc. R. Soc. A 461 (2005) 1775-1809], who assumed sliding friction in their analysis, it is found that the self-induced jumping can also occur in the absence of friction at the very beginning of the motion. The free motion after the contact is lost and impact of the body when it again makes contact with the plane is discussed. The motion of a spheroid and a disk which illustrate the results of the general theory are discussed in some detail. 相似文献
4.
Mei Cheng Guang Meng Jianping Jing 《Archive of Applied Mechanics (Ingenieur Archiv)》2006,76(3-4):215-227
The non-linear dynamic behaviors of a rotor-bearing-seal coupled system are investigated by using Muszynska’s non-linear seal fluid dynamic force model and non-linear oil film force, and the result from the numerical analysis is in agreement with the one from the experiment. The bifurcation of the coupled system is analyzed under different operating conditions. It is indicated that the dynamic behavior of the rotor-bearing-seal system depends on the rotation speed, seal clearance and seal pressure of the rotor-bearing-seal system. The system state trajectory, Poincaré maps, frequency spectra and bifurcation diagrams are constructed to analyze the dynamic behavior of the rotor center. Various non-linear phenomena in the coupled system, such as periodic motion and quasi-periodic motion are investigated. The results show that the system has the potential for chaotic motion. The study may contribute to a further understanding of the non-linear dynamics of such a rotor-bearing-seal coupled system. 相似文献
5.
《International Journal of Non》2006,41(6-7):850-859
In this article an analytical solution of equations of motion of a rigid disk of finite thickness rolling on its edge on a perfectly rough horizontal plane under the action of gravity is given. The solution is given in terms of Gauss hypergeometric functions. The integrability results are used to construct various bifurcation diagrams of the steady motion of the disk. The bifurcations of the steady motion of a disk on a rough plane complements the author's bifurcation analysis of the steady motion of the disk on a smooth plane ( [M. Batista, Steady motion of a rigid disk of finite thickness on a horizontal plane, Int. J. Non-Linear Mech. 41 (4) (2006) 605–621]). 相似文献
6.
A method based on a perfect rigid-plastic body model is developed to analyze the dynamic behavior of hinged or clamped polygonal
plates that have a perfectly rigid insert and rest on a viscoelastic foundation with supports. The plate is subject to an
arbitrary blast load of high intensity uniformly distributed over the plate surface. Two cases of plate deformation are examined.
In each of the cases, equations of motion are derived and realization conditions are analyzed. Analytic expressions for the
deformation time and the maximum residual deflection are derived in the case of an arbitrary load of medium intensity and
in the case of high-intensity load described by a rectangular function. Examples of numerical solutions are given
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 1, pp. 99–110, January 2008. 相似文献
7.
M. V. Shamolin 《Journal of Applied Mechanics and Technical Physics》2016,57(4):611-622
A mathematical model of the influence of a medium on a rigid body with some part of its external surface being flat is considered with due allowance for an additional dependence of the moment of the medium action force on the angular velocity of the body. A full system of equations of motion is given under quasi-steady conditions; the dynamic part of this system forms an independent third-order system, and an independent second-order subsystem is split from the full system. A new family of phase portraits on a phase cylinder of quasi-velocities is obtained. It is demonstrated that the results obtained allow one to design hollow circular cylinders (“shell cases”), which can ensure necessary stability in conducting additional full-scale experiments. 相似文献
8.
Simultaneous axial and torsional oscillations of a rigid disk attached to an elastomeric shaft are investigated. Five cases are solved exactly. The uncoupled, small amplitude axial and torsional oscillations of the disk are investigated for neo-Hookean and Mooney-Rivlin shafts with static stretch. The finite torsional vibration of the load superimposed on a static stretch of the shaft is studied for the Mooney-Rivlin model. Solutions for both small and finite amplitude, uniaxial vibrations of the body superimposed on a pretwisted neo-Hookean shaft with static stretch are derived. Simple bounds on the period for the finite motion are provided; and various universal frequency relations for neo-Hookean and Mooney-Rivlin materials are identified.Finally, the main problem of finite, uniaxial vibrations accompanied by a small twisting motion is studied for the neo-Hookean model. The exact periodic solution for the axial response is obtained; and the coupled, small torsional motion is then determined by Hill's equation. A stability criterion for the Mathieu-Hill equation is used to obtain stability maps in a physical parameter space. Geometrical conditions sufficient for universal stability of the motion are read from this graph. Instability of the torsional oscillation, the beating phenomenon and exchange of energies, and the relation of the stability diagram to amplitude bounds on the uncoupled, linearized motion sufficient to assure universal stability predicted for small amplitude vibrations, are discussed and described graphically with the aid of a numerical model. It is shown that an unstable configuration may be stabilized by increasing the diameter of the disk. 相似文献
9.
N. V. Malai E. R. Shchukin A. A. Stukalov K. S. Ryazanov 《Journal of Applied Mechanics and Technical Physics》2008,49(1):58-63
The steady motion of a uniformly heated spherical aerosol particle in a viscous gaseous medium is analyzed in the Stokes approximation
under the condition that the mean temperature of the particle surface can be substantially different from the ambient temperature.
An analytical expression for the drag force and the velocity of gravity-induced motion of the uniformly heated spherical solid
particle is derived with allowance for temperature dependences of the gaseous medium density, viscosity, and thermal conductivity.
It is numerically demonstrated that heating of the particle surface has a significant effect on the drag and velocity of gravity-induced
motion.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 1, pp. 74–80, January–February, 2008. 相似文献
10.
A. V. Skvortsova 《Fluid Dynamics》1988,23(5):684-689
In [1–3] a series of problems of the motion of heat sources at a temperature higher than the melting point of the surrounding
medium was considered. The heat source could be a laser beam or a hot body. Here, the case of a thin wedge heated to a temperature
higher than the melting point of the surrounding medium and moving at a constant velocity is investigated. The velocity is
high enough for the molten layer formed to be thin. The problem is solved by the method of integral relations. The shape of
the molten zone, the drag on the wedge and other flow characteristics of the melt are determined.
Moscow. Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 52–57, September–October, 1988. 相似文献
11.
M. V. Shamolin 《International Applied Mechanics》2001,37(6):769-777
A dynamic model of the interaction of a rigid body with a jet flow of a resistant medium is considered. This model allows us to obtain three-dimensional analogs of plane dynamic solutions for a solid interacting with the medium and to reveal new cases where the equations are Jacobi integrable. In such cases, the integrals are expressed in terms of elementary functions. The classical problems of a spherical pendulum in a flow and three-dimensional motion of a body with a servoconstraint are shown to be integrable. Mechanical and topological analogs of these problems are found 相似文献
12.
I. V. Simonov K. Yu. Osipenko 《Journal of Applied Mechanics and Technical Physics》2004,45(3):428-439
The deep penetration of a thin body with a blunt nose and rear into a lowstrength medium is explored. The motion of the body is described by a system of autonomous integrodifferential equations using the physical model of a separated asymmetric flow over the body and the localinteraction method. An analytical calculation of the Lyapunov stability boundary for straightline motion is performed for bodies with a parabolic meridian. The dependences of the dynamic stability of the body on various parameters are studied numerically. Curved motion paths are constructed in the region of instability, and the classification of paths proposed in previous studies of the motion of pointed bodies is confirmed. It is shown that an reverse ejection is possible when a blunt impactor enters a semiinfinite target. It is established that there is a fundamental possibility of attaining a path close to a specified one and that there is a weak dependence of motion characteristics with a developed separation on the separation angle. Examples are given of calculations of the evolution of the lateral load, the transverse force and moment, and the strength margin of the body using the theory of dynamic bending of a nonuniform rod. 相似文献
13.
A multiparameter family of phase portraits in the dynamics of a rigid body interacting with a medium
M. V. Shamolin 《Moscow University Mechanics Bulletin》2011,66(3):49-55
The problem of plane-parallel motion of a uniform symmetric rigid body interacting with a medium only through a flat region
of its outer surface is studied. The force field is constructed on the basis of information on the properties of jet flow
under quasistationarity conditions. The motion of the medium is not studied. The problem of rigid body dynamics is considered
for the case when the characteristic time of motion of the body relative to its center of mass is comparable with the characteristic
time of motion of this mass center. 相似文献
14.
The dynamic coupled thermoelastic problem formulation and the thermodynamically consistent theory of inelastic behavior of
materials are used to solve an axisymmetric problem for a steel disk subject to a heat pulse at the center. The temperature
dependence of the physical and mechanical properties of the disk is taken into account. The problem is solved by the FEM.
The evolution in time and features of the strain-stress and thermal states of the disk and the dynamic effects accompanying
the processes of heating and gradual cooling are studied
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 5, pp. 45–57, May 2008. 相似文献
15.
Milan Batista 《International Journal of Non》2006,41(4):605-621
The article discusses the steady motion of a rigid disk of finite thickness rolling on its edge on a horizontal plane under the influence of gravity. The governing equations are presented and two cases allowing for a steady-state solution are considered: rolling on consistently rough ground and rolling on perfectly smooth ground. The conditions of steady motion are derived for both kinds of ground and it is shown that the possible steady motion of a disk is either on a straight line or in a circle. Oscillations about steady state are discussed and conditions for stable motion established. The bifurcations of steady motions on a smooth surface are also considered. 相似文献
16.
R. G. Yakupov 《Journal of Applied Mechanics and Technical Physics》2008,49(2):306-312
Wave processes in a semi-infinite rod located in an elastic medium under pulsed loading by an external distributed force are
considered. A system of two differential equations of motion of Timoshenko’s beam theory is solved with the use of the Laplace
transform in time. The resultant integrals are determined numerically. The changes in bending and bending moment over the
longitudinal coordinate at different times are demonstrated.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 2, pp. 178–184, March–April, 2008. 相似文献
17.
R. I. Leine 《Archive of Applied Mechanics (Ingenieur Archiv)》2009,79(11):1063-1082
This paper is concerned with the dominant dissipation mechanism for a rolling disk in the final stage of its motion. The aim
of this paper is to present the various dissipation mechanisms for a rolling disk which are used in the literature in a unified
framework. Furthermore, new experiments on the ‘Euler disk’ using a high-speed video camera and a novel image analysis technique
are presented. The combined experimental/theoretical approach of this paper sheds some more light on the dominant dissipation
mechanism on the time-scale of several seconds. 相似文献
18.
The incidence of a plate and a disk of finite mass on a free water surface and the subsequent inertial motion are investigated. The effect of the air medium above the liquid is neglected.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 177–179, May–June, 1989. 相似文献
19.
The cooperative motion of a fluid and a parabolic tank is modeled. Use is made of a discrete model based on the Hamilton–Ostrogradsky
principle for an arbitrary body of revolution and a non-Cartesian parametrization of the domain occupied by the fluid. A set
of coordinate functions satisfying kinematic boundary conditions and solvability conditions is set up. The discrete model
is used to study the transients in the system. It is shown that the model adequately describes the nonlinear dynamic properties
of the system 相似文献
20.
The linear stability theory for the Horton–Rogers–Lapwood problem is extended to the case where the porous medium is saturated
by a nanofluid with thermal conductivity and viscosity dependent on the nanoparticle volume fraction. The effects of Brownian
motion and thermophoresis are considered. In conjunction with the Brownian motion, the nanoparticle fraction becomes stratified,
and hence the viscosity and the conductivity are stratified. The nanofluid is assumed to be dilute and this enables the porous
medium to be treated as a weakly heterogeneous medium with variation, in the vertical direction, of conductivity and viscosity.
In turn this allows an approximate analytical solution to be obtained. 相似文献