Advanced Materials Research Vol. 1040

Abstract: The paper presents the numerical research heat mass transfer and hydrodynamics in the motion of viscous fluid in the rectangular cavity in the consideration of the crystallization process. The hydrodynamic Figure of viscous fluid and temperature fields obtained. The impact of hydrodynamic parameters and geometrical characteristics for forming crystallization front is studied.

Abstract: The article examines the effect of gravitational force on the operation of a liquid-type autobalancing device. Results of the mathematical analysis and experiments are presented. When performing a hydrodynamic calculation of the rotation speed the effects of gravitational and centrifugal forces as well as the effect of the liquid’s force friction against the housing are considered. The analysis results show that the speed at which the gravitational force in an autobalancing device may be negligible is greatly dependent upon the radius and coefficient of gravitation. Moreover, the less the gravitational coefficient and the greater the radius, the greater the angular velocity of an autobalancer. As a result of the conducted investigation, the speeds evaluating the possibility of using liquids as balancers at low rotation speeds are provided in this paper.

Abstract: The loading process, in which the shear action on the boundary plane changes both the intensity and direction, is considered by the example of a one-dimensional plane problem for non-linear elastic incompressible half-space. It is shown that the solution in the front region of the shock wave is determined by a nonlinear evolution equations system in the space regions where the nonlinearity of the medium becomes a significant factor. The general solution of the evolution system was obtained. The particular solution of the evolution system for one of the most simple boundary conditions was considered as an example.

Abstract: Self-similar solution of two-dimensional problem of interaction between a plane longitudinal shock wave and free boundary of elastic half-space is considered. It is suggested that the intensity of this wave is constant. Feasible combinations of wave surfaces which may be generated in elastic medium as a result of such interaction are investigated. Choosing of unique physically admissible mode of deformation propagation from among mathematically possible wave patterns is related to shockwave evolutionary condition and the second law of thermodynamics.

Abstract: The present paper is devoted to research and development of methods of advanced static and dynamic analysis of structures, based on application of flexible hierarchical substructure models “foundation – structure – equipment – pipelines”, implemented in certified software application packages, convenient for practical industrial use. Contemporary finite element software application packages (universal – ANSYS, ABAQUS – and self-engineered – STADYO, ASTRA-NOVA products) are used for justification of nuclear power facilities.

Abstract: The distinctive paper is devoted to correct multilevel discrete-continual finite element method (DCFEM) of structural analysis based on precise analytical solutions of resulting multipoint boundary problems for systems of ordinary differential equations with piecewise-constant coefficients. Corresponding semianalytical (discrete-continual) formulations are contemporary mathematical models which currently becoming available for computer realization. Major peculiarities of DCFEM include universality, computer-oriented algorithm involving theory of distributions, computational stability, optimal conditionality of resulting systems and partial Jordan decompositions of matrices of coefficients, eliminating necessity of calculation of root vectors.

Abstract: The technology of manufacturing of metallurgical equipment using plasma deposition of the active layer of high speed steels hardness is analysed. This paper presents a thermal cycle and device for its implementation in plasma surfacing of metallurgical by speed steels equipment.

Abstract: In this article the development of the perspective vibration protection device is described. The theory suggests the development of 3D-vibration isolator devices, which have power characteristics with zero stiffness area. A spatial vibroisolator is presented as an elastic element and stiffness compensator in-parallel of this element to obtain this specific area on power characteristic. This methodology allows us to make three-dimensional (3D) vibration isolator with electromagnetic stiffness compensator. This isolator allows to delete the vibration fluctuations in all three axes of space simultaneously. A spatial vibroisolated device consists of an elastic element and parallel 3D-electromagnetic stiffness compensator. An electromagnetic stiffness compensator is a two counter-mounted electromagnetic disks. Each disk is made as six electromagnetic or magnetic disconnected coils, and they are located two by two along three axes of space. The construction of one-dimensional vibration isolator with an electromagnetic stiffness compensator is presented in this article. Three-dimensional vibration isolator can be used in any area of mechanic, engineering, vibration dumping technique, which has a negative effect on human health and devices performance.

Abstract: The following article considers mathematic modeling of hydroimpulsive power systems. Using the MATLab software environment the author studies the influence of design parameters on the formed impulse. Consequently a new headless hydroimpulsive power mechanism is offered and described in detail and a basic diagram is given. This system can be used for designing new hydroimpulsive rock-drilling machines to intensify the process of drilling.

Abstract: In this paper we propose novel techniques of ceramic shell mold production with lost-wax method of cast as well as technological methods aimed at fracture strength improvement. The distinguishing characteristic of application of these molds is the possibility to use them without buckling agent resulting in decrease of prime cost in casting.