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1.
The problem of the motion of a homogeneous circular cylinder along a fixed rough inclined plane is discussed. It is assumed that the cylinder is supported on the plane by its base and executes continuous motion. The frictional forces and moment are calculated within the limits of the dynamically consistent model proposed by Ivanov, for which the pressure distribution over the contact area is non-uniform. A qualitative analysis of the dynamics of the cylinder is given in the case when the slope of the plane is less then the Coulomb coefficient of friction.  相似文献   

2.
The present article describes the determination of thermal stresses in an orthotropic cylinder with an axially symmetric temperature field taking into account the change in the elasticity constants over the cylinder radius. A closed solution is given for constant elasticity coefficients.P. I. Baranov Central Institute of Aircraft-Engine Building, Moscow. Translated from Mekhanika Polimerov, No. 2, pp. 310–314, March–April, 1972.  相似文献   

3.
The nonlinear vibrations of a viscoelastic cylinder with an elastic shell subjected to two harmonic forces are investigated using the averaging scheme described in [3, 4]. Nonresonance, resonance, and subharmonic vibrations are examined. It is shown that the presence of viscosity in the system leads to a single stationary equilibrium position for which the stability conditions are given.V. I. Lenin Tashkent State University. Translated from Mekhanika Polimerov, No. 4, pp. 691–697, July–August, 1973.  相似文献   

4.
Differential search games with simple motions of objects on an infinite circular cylinder are approached geometrically, using sets whose structure depends on time. Sufficient conditions for detection with the corresponding strategies are given. New kinds of problems are proposed, their connections with the initial parameters are investigated. Translated fromMatematicheskie Zametki, Vol. 58, No. 5, pp. 762–772, November, 1995. This work was partially supported by the Russian Foundation for Basic Research under grant No. 242 95-01-01471.  相似文献   

5.
The present investigation is concerned with a study effect of non-homogeneous on the elastic stresses in rotating orthotropic infinite circular cylinder subjected to certain boundary conditions. Closed form stress solutions are obtained for rotating orthotropic cylinder with constant thickness for three cases: (1) a solid cylinder; (2) cylinder mounted on a circular rigid shaft; and (3) cylinder with a circular hole at the center. Analytical expressions for the components of the displacement and the stress in different cases are obtained. The effect of the rotation and non-homogeneity on the displacement and stress are studied. Numerical results are given and illustrated graphically for each case is considered. The effects rotating and non-homogeneity are discussed. Comparisons are made with the results predicted in the presence and absence of rotation.  相似文献   

6.
An elastic-plastic solution is presented for an internally pressurized thick-walled plane strain cylinder of an elastic linear-hardening plastic material. The solution is derived in a closed form using a strain gradient plasticity theory. The inner radius of the cylinder enters the solution not only in non-dimensional forms but also with its own dimensional identity, which differs from that in classical plasticity based solutions and makes it possible to capture the size effect at the micron scale. The classical plasticity solution of the same problem is recovered as a special case of the current solution. To further illustrate the newly derived solution, formulas and numerical results for the plastic limit pressure are provided. These results reveal that the load-carrying capacity of the cylinder increases with decreasing inner radius at the micron scale. It is also seen that the macroscopic behavior of the pressurized cylinder can be well described by using classical plasticity based solutions.  相似文献   

7.
An elastic-plastic solution is presented for an internally pressurized thick-walled plane strain cylinder of an elastic linear-hardening plastic material. The solution is derived in a closed form using a strain gradient plasticity theory. The inner radius of the cylinder enters the solution not only in non-dimensional forms but also with its own dimensional identity, which differs from that in classical plasticity based solutions and makes it possible to capture the size effect at the micron scale. The classical plasticity solution of the same problem is recovered as a special case of the current solution. To further illustrate the newly derived solution, formulas and numerical results for the plastic limit pressure are provided. These results reveal that the load-carrying capacity of the cylinder increases with decreasing inner radius at the micron scale. It is also seen that the macroscopic behavior of the pressurized cylinder can be well described by using classical plasticity based solutions.  相似文献   

8.
An analytical method is presented to investigate the bending-torsion vibration characteristics of a cylinder with an arbitrary cross-section and partially submerged in water. The compressibility and the free surface waves of the water are considered simultaneously in the analysis. The exact solution of structure–water interaction is obtained mathematically. Firstly, the analytical expression of the velocity potential of the water is derived by using the method of separation of variables. The unknown coefficients in the velocity potential are determined by the longitudinal and circumferential Fourier expansions along the outer surface of the cylinder and are expressed in the form of integral equations including the unknown dynamic bending deflection and torsional angle of the cylinder. Secondly, the force and torque acting on the cylinder per unit length, provided by the water, are obtained by integrating the water dynamic pressure along the circumference of the cylinder. The general solution of bending-torsion vibration of the cylinder under the water dynamic pressure is derived analytically. The integral equations included in the velocity potential of the water can be solved exactly. Finally, the eigenfrequency equation of cylinder–water interaction is obtained by means of the boundary conditions of the cylinder. Some numerical examples for elliptical columns partially submerged in water are provided to show the application of the present method.  相似文献   

9.
In this paper a study of the secondary flow on an infinite yawed cylinder in a compressible stream is made at stagnation for unit Prandtl number and for a given Mach number. The secondary flow profiles are calculated for different edge inclination angles. The chordwise and spanwise velocity profiles given by Crabtree1 are used here in the calculation. It is found that the secondary flow profiles are the same for complementary edge inclination angles and they are maximum for the edge inclination angle of 45°. A comparison with the incompressible flow profiles2 is made. It is found that the magnitude of the secondary flow profiles in a compressible stream is less than that in an incompressible stream for the same edge inclination angle.  相似文献   

10.
Wave processes in an orthotropic cylinder are analyzed. Harmonic oscillations are considered for which the original problem is reduced to a system of ordinary differential equations. This system is solved by the numerically stable discrete-orthogonalization method. Discrete curves for specific problems are given.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 56, pp. 75–78, 1985.  相似文献   

11.
A theoretical investigation of the unsteady two-dimensional flow of a viscous, incompressible fluid normal to a thin elliptic cylinder is described. The cylinder, which is started impulsively from rest in an open field, continues to move with uniform velocity for the remainder of the problem. Using a vorticity-streamfunction formulation of the full Navier-Stokes equations, transformation techniques are employed to find the initial flow. Strategies which employ boundary layer theory and series expansions of the flow variables to find flow solutions for small values of time are outlined.  相似文献   

12.
The scattering of sound waves by an isotropic elastic circular cylinder of infinite extent in a water of finite depth is investigated taking into account the shear waves that can exist in addition to compressional waves in scatterers of solid material. The axis of the cylinder is parallel to the water level. The reflected and transmitted energies are plotted for the various values of the radius of the cylinder, and the farfield scattered pressure is obtained for various depth and presented in a graphical form. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

13.
《Applied Mathematics Letters》2005,18(9):1009-1012
In this note a proof for nonexistence of a solution for reverse radial stagnation flow on a cylinder is given. The results are valid for either suction or blowing on the cylinder wall.  相似文献   

14.
The theory of functions of a complex variable is used to construct an approximate solution for the stationary oscillations of an elliptical cylinder with longitudinal elliptical cavities. Some numerical results are presented for a cylinder with a single cavity. Donetsk State University. Translated from Teoreticheskaya i Prikladnaya Mekhanika, No. 30, pp. 132–137, 1999.  相似文献   

15.
A cooling fin attached to a cylinder of circular cross section is considered. We obtain sharp upper and lower estimates for the maximum heat dissipation under the constraint that the total weight of the fin should not exceed a given bound. It is assumed that the boundary of the cylinder has a constant temperature and that Newton's law of cooling holds.This research was supported by the International Atomic Energy Agency and the United Nations Educational, Scientific, and Cultural Organization, International Center for Theoretical Physics, Miramare, Trieste, Italy.The author wishes to thank Professor Abdus Salam, the International Atomic Energy Agency, and UNESCO for hospitality at the International Center for Theoretical Physics, Trieste, Italy. Thanks are also due to the University Grants Commission, New Delhi, India, for a travel Grant, and the University of Mysore, Mysore, India, for granting the necessary leave.On leave of absence from the University of Mysore, Mysore, India.  相似文献   

16.
The incompressible flow of a Newtonian fluid over a backward-facing step is investigated numerically. The geometry is an annular pipe in which the radius of the inner cylinder decreases suddenly. Keeping the radial expansion ratio fixed axisymmetric flows are computed for outlet radius ratios from 0.1 to 1 (ratio of the inner to the outer outlet radius). The Reynolds number at which the flow separates from the outer cylinder decreases as the outlet radius ratio decreases for constant inlet geometry. The growth with Reynolds number of the recirculation zone on the inner outlet cylinder just behind the step is strongly reduced when the recirculation zone on the outer cylinder is established. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

17.
The present article considers the use of the random anisotropy potential to investigate the stress field in an anisotropic cylinder. The mechanical properties of the body are considered to be determined and the displacements at the boundary to be random. The general solution to the elasticity-theory problem for the displacements in an anisotropic body is expressed in the form of the sum of the general solution of a homogeneous equation system and the special solution of an inhomogeneous system. Determination of the latter reduces to solution of a system of integral equations with a common kernel in the form of Green functions of the Laplacian. The first- and second-order moments for the displacements and stresses are given, a numerical example is examined, and the convergence of the approximation-calculation procedure is investigated.S. M. Kirov Ural Polytechnic Institute, Sverdlovsk. Translated from Mekhanika Polimerov, No. 2, pp. 315–320, March–April, 1972.  相似文献   

18.
The antiplane strain of an anisotropic elliptical cylinder with a crack is examined. An infinite system of linear algebraic equations is obtained from the boundary conditions on the cylinder surface to determine the constants in the complex potential of the problem. Detailed numerical investigations are performed of the influence of the geometric and elastic characteristics of the cylinder on the magnitude of the stress intensity coefficients near the outer edge.Translated from Teoreticheskaya i Prikladnaya Mekhanika, No. 18, pp. 28–34, 1987.  相似文献   

19.
The axisymmetric flow of a non-Newtonian liquid with an exponential rheological law between two coaxial cylinders is considered for the case when the outer cylinder is fixed and the inner cylinder moves freely together with the liquid. At the outer cylinder the liquid moves either with or without slip. The individual theoretical conclusions are confirmed by the experimental results.Mekhanika Polimerov, Vol. 3, No. 1, pp. 151–155, 1967  相似文献   

20.
We consider the problem of scattering of two-dimensional sound pulses by a rigid circular cylinder embedded in a cylindrically stratified inhomogeneous medium. The line source is parallel to the axis of the cylinder. It is assumed that the velocity of soundc is given byc ?1=pr q, wherep andq are real constants andp>0. The method of dual integral transformation developed by Friedlander is used. The solution in terms of pulse propagation modes gives the diffracted pulse and the method of steepest descents yields the geometrical acoustic field.  相似文献   

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