A.V. Zvyaguin

Статья посвящена разработке численного метода определения коэффициента интенсивности напряжений для плоских задач механики разрушения, учитывающего наличие кривизны линии трещины. Получены новые представления бигармонических функций, с помощью которых были построены аналитические решения задач об упругой плоскости, ослабленной трещиной в виде дуги...

В процессе развития различных микродефектов в телах могут образовываться сложные системы трещин произвольной конфигурации. В работе представлена методика численного моделирования сложных ломаных трещин, позволяющая анализировать такие системы. При помощи предложенного авторами метода удается найти поля напряжений, перемещений, а также коэффициенты...

Various celestial bodies contain cracks. Also, cracks can be in the skin of aircraft, while their growth is one of the main mechanisms for the breakup of structures. This paper presents a study of one and two rectangular cracks. The influence coefficient (the ratio of the stress intensity factors for the fracture system to the corresponding value f...

One of the main problems of fracture mechanics is to describe the behavior of media with cracks. At the same time, more and more attention is paid to the study of large systems, including periodic structures. For several cracks, the coefficient of influence is considered to be an important parameter. It is the ratio of the stress intensity factor c...

All celestial bodies have defects in the form of cracks. Some of the bodies are large. Colliding with such objects can be dangerous. Therefore, the problem of grinding such bodies remains very urgent. In order to avoid large financial costs, you need to know where to strike in order to achieve the greatest effect. This paper studies the behavior of...

One of the mechanisms of destruction of a solid is the formation and growth of “micro” and “macro” cracks. This task is especially acute for space objects. A microcrack in the body of the spacecraft practically does not affect its mechanical strength, but it can lead to depressurization of the body, which can lead to the loss of life support for th...

The mutual influence of three-dimensional disk-shaped cracks located in parallel planes of an elastic medium is studied. The medium is under tensile stress directed perpendicular to the crack planes. The cracks are modeled by mathematical cuts of the continuous medium with the possibility of a strong discontinuity of the displacement field on the f...

A conservative difference scheme with linear dependence of the pressure on the density of gas is proposed for gas dynamics equations. The scheme allows us to simulate 1-D flows inside a cylindrical domain with time-variable cross-sections and guarantees the positive sign of the density function.

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 expr...

The problem of motion of a concentrated load along the surface of a fluid-saturated porous medium is studied for a subsonic range of speeds. An analytical solution is found. It is shown that there exists a critical speed equal to the speed of the Rayleigh-type surface waves in a porous elastic medium. If this critical speed is exceeded, then the be...

The paper deals with a dynamic contact problem in the presence of friction forces in the transonic range of punch velocities, where the punch velocity exceeds the transverse wave velocity but is still less than the longitudinal wave velocity. It is shown that there exists a critical velocity at which the solution structure and the character of its...

This paper is devoted to the peculiarities of a process of inertial tether system deployment of the great length (tens of kilometers). And one of the main practical issues of this article is the behavior of maximum oscillation amplitude. First of all the exact analytical solution of the original problem is received. Furthermore it is shown that rat...

The problem of asymmetrical movement of a thin rigid impactor in elastic material is considered with subsonic and transonic velocities. For all considered range of velocities the flow diagram was determined for contours in the forms of wedge and ogive. There is a limiting speed value when the impactor moves with velocity higher than the speed of tr...

This paper develops a theoretical solution for the problem of determining thin wing's lift force while moving near flat surface (a screen). The solution is determined under the assumption of fluid being ideal and incompressible. The Chaplygin–Zhukovsky hypothesis of rear-edge-limited solution is taken into consideration. The solution of a problem i...

The two-dimensional problems of thin body motion in fluid parallel to the boundary at a distance, comparable with the length of the body, are regarded. In particular, resistance and lift forces in thin body motion parallel to free surface and parallel to rigid surface are determined and compared with existing solutions for resistance and lift force...

The two-dimensional problem of high velocity moving slender body interaction with fluid free surface was regarded. Gravity was neglected as compared with fluid inertia. The problem is relevant to underwater motion of a bullet or shell, which could take place in orbital collisions of particles with fluid-filled containments. The problem is also rele...

The statics and dynamics of a flexible extensible elastic thread wound on a reel and interacting with the surface by the dry friction law are studied. Both the thread loading and unloading are analyzed. The depth of perturbation penetration is found.

The paper is aimed at studying the peculiarities of dynamical behavior of tether in its deployment in low Earth orbit during YES2 experiment in Foton-M3 mission, and performing flight data analysis with account of these effects. The analysis in the first part of the paper uses as input a pre-provided tension profile for the mission (resulting from...

The problem of thin body high speed motion in compressible fluid near free surface is regarded. The problem is relevant to thin impactor high speed penetration into fluid filled containment. The resistance and lift forces strongly depend on the depth of body motion under free surface. Due to that reason the response of containment on high velocity...

The two-dimensional problem of thin obstacle interaction with compressible fluid flow near free surface under microgravity was regarded. The fluid was assumed occupying infinite semi-space, gravity was neglected as compared with fluid inertia. The obtained exact solution shows that for relatively thin layer the resistance force does not depend on t...

The practical problem arises in enhancing oil recovery and is relevant to hydraulic fracturing process and subsequent frontal displacement of fluids from subterranean environment. Entrapment of residual fluid by the displacing one lowers down the displacement quality leaving most of residual viscous fluid in porous matrix. The present paper provide...

The practical problem arises in enhancing oil recovery and is relevant to hydraulic fracturing process and subsequent frontal displacement of fluids from subterranean environment. Entrapment of residual fluid by the displacing one lowers down the displacement quality leaving most of residual viscous fluid in porous matrix. The present paper provide...

The two-dimensional problem of thin body motion in an elastic semi-space with velocity parallel to the free surface was regarded. The obtained solution shows that for relatively thin layer the resistance force does not depend on the layer thickness, but depend on body length and inclination angle, and surpasses twice the respective values for the i...