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Vol 73, No 3 (2018)

Article

A New Case of an Integrable System with Dissipation on the Tangent Bundle of a Multidimensional Sphere

Shamolin M.V.

Abstract

The equations of motion for a dynamically symmetric n-dimensional fixed rigid body-pendulum situated in a rioricoriservative force field are studied. The form of these equations is taken from the dynamics of real fixed rigid bodies placed in a homogeneous flow of an incident medium. The complete list of transcendental first integrals expressed in terms of finite combinations of elementary functions is found.

Moscow University Mechanics Bulletin. 2018;73(3):51-59
pages 51-59 views

Formulation of Problems in the General Kirchhoff—Love Theory of Inhomogeneous Anisotropic Plates

Gorbachev V.I., Kabanova L.A.

Abstract

In this paper we study the procedure of reducing the three-dimensional problem of elasticity theory for a thin inhomogeneous anisotropic plate to a two-dimensional problem in the median plane. The plate is in equilibrium under the action of volume and surface forces of general form. À notion of internal force factors is introduced. The equations for force factors (the equilibrium equations in the median plane) are obtained from the thickness-averaged three-dimensional equations of elasticity theory. In order to establish the relation between the internal force factors and the characteristics of the deformed middle surface, we use some prior assumptions on the distribution of displacements along the thickness of the plate. To arrange these assumptions in order, the displacements of plate points are expanded into Taylor series in the transverse coordinate with consideration of the physical hypotheses on the deformation of a material fiber being originally perpendicular to the median plane. The well-known Kirchhoff—Love hypothesis is considered in detail. À closed system of equations for the theory of inhomogeneous anisotropic plates is obtained on the basis of the Kirchhoff—Love hypothesis. The boundary conditions are formulated from the Lagrange variational principle.

Moscow University Mechanics Bulletin. 2018;73(3):60-66
pages 60-66 views

Waves on the Surface of an Ideal Incompressible Heavy Fluid under Wind Loads

Zvyagin A.V., Sapunov K.V.

Abstract

The gravity-forced motion of an ideal incompressible fluid of infinite depth is studied when a periodic pressure is applied to the surface of the fluid. This problem is solved on the basis of the small amplitude wave theory. The analytical solutions for the velocity potential, the velocity field, and the shape of the free surface are found. An expression for the horizontal force is obtained in the case of a traveling wave.

Moscow University Mechanics Bulletin. 2018;73(3):67-72
pages 67-72 views