No 3 (2016)
Ultimate bearing capacity and strength of long composite columns
Abstract
Based on the strength calculation the method of determining the load bearing capacity of pipe-concrete columns under the action of the main compressive stress is proposed. The pipe-concrete column is considered as the transversely isotropic composite structure. The mathematical apparatus of the theory of elasticity is used when calculating the carrying capacity of the concrete core, the mechanic of shells is used for the pipe calculation. The load bearing capacity is determined from the condition of the shell-tube destruction. As an example the calculation's results of determining pipe-concrete column carrying capacity for the particular geometry of the steel pipe according to the tensile strength of the pipe material are shown for some grades of concrete filling pipe.
Applied Mathematics and Control Sciences. 2016;(3):12-22
 |  |
BEHAVOR OF COVERS OF THE HEATALLOCATING ELEMENTS AT OPERATON TAKING INTO ACCONT RESIDUAL STRESSES
Abstract
In work the technique of taking note of the operational modes taking into account residual tension on premature cracking of zirconium covers of the heatallocating elements (TVEL) used in thermonuclear reactors is presented. Classical approaches of applied mechanics are applied to calculations maximum-permissible loadings and technological residual tension in thin-walled covers of fuel elements. The technique is applied to determination of the maximum district tension in the operational modes for various values of internal pressure for covers with different thickness of a wall for a case when the operational modes are known. Maximum permissible tension depending on the level of district residual tension for various alloys of zirconium in a case when levels of residual tension are determined is calculated.
Applied Mathematics and Control Sciences. 2016;(3):23-34
| |
Modeling of upsetting process of a cylindrical workpiece
Abstract
The modeling of upsetting process of a cylindrical workpiece in the software package QForm 2D/3D presented. Numerical experiment allowed us to determine the rational technological parameters of the process and to assess the stability of the shape of the workpiece during the deformation with the aim of obtaining quality products. The features of the process of deformation at a deposit of the workpieces were investigate, related to the physical characteristics of the material, a scale factor types of equipment and technological parameters of the process. The obtained results can be used to solve technological problems related to the improvement of processes of production with the aim of increasing automation of production and quality of finished products, reduce the cost of their production.
Applied Mathematics and Control Sciences. 2016;(3):35-41
| |
Mechanic of plastic deformation and optimization of hydro-pressing conditions
Abstract
In work conditions of plastic deformation are considered at hydromechanical pressing, as one of versions of process of pressing. An excellent condition of hydromechanical pressing from other types of pressing is the possibility to supervise movement of preparation and to prevent it flying in a final stage of pressing that is characteristic for other types of pressing. Formulas of components of the general pressure of hydromechanical pressing and optimum angle cone matrixes a press the tool are received. Optimization of angles of a matrix for hydromechanical pressing is lead. Dependences of the attitude of a pressure of pressing to resistance of deformation of a pressed material from an extract from which availability of optimum angles cone a press matrixes follows are constructed.
Applied Mathematics and Control Sciences. 2016;(3):42-50
| |
CALCULATION OF STRAIN bevel gears during heat treatment
Abstract
In the work the analysis of geometrical changes of the workpiece spiral bevel gears which arise in the course of heat treatment. The proposed new geometry of the workpiece before performing a heat treatment with the aim of getting as close as possible to the geometry of the design documentation after heat treatment. This will allow to improve indicators of maintainability, durability, also to reduce the loss of metal, and thus to increase the efficiency of manufacturing parts that is relevant and important questions of engineering. The comparison of the change of size after heat treatment of the part according to the control, the curves of the distribution of the size of the deviations, the proposed method of compensation of deformation after heat treatment.
Applied Mathematics and Control Sciences. 2016;(3):51-59
| |
About Linear singular second-order equations with deviating argument
Abstract
In the article we have got conditions of solvability Cauchy’s problem for a linear functional differential equation cannot be improved concerning parameters k and m . There is also talk about application of results obtained for researching initial-value problem for quasi-linear singular equation on the solvability.
Applied Mathematics and Control Sciences. 2016;(3):60-66
| |
CONSTITUTIVE EQUATIONS FOR SHAPE MEMORY ALLOYS IN VIEW OF THE PHASE TRANSFORMATION AND THE PLASTIC DEFORMATION
Abstract
In the framework of infinitesimal and finite deformations the models have been constructed to describe the austenite-to-martensite phase transformation and the plastic deformation in the shape memory alloys. The total deformation was separated into elastic, thermal, phase transformation and plastic parts. The change in the elastic moduli in the processes of direct (austenite-to-martensite) and reverse (martensite-to-austenite) phase transformations was taken into account. A linear dependence of the characteristic temperatures on the stress intensity was used. The proposed model has been tested on two simple problems of bar tension with considering of the plastic strain and without.
Applied Mathematics and Control Sciences. 2016;(3):67-78
| |
Management of products quality formation process at the industrial enterprise
Abstract
The general mathematical formulation of the products quality management problem throughout products life cycle is considered. It is believed that the product quality formation process depends on a combination of processes: planning, manufacturing, sales, service, etc. Quality products functionals are formulated. On the basis of these functionals the optimality criteria and constraints in a control problem are constructed. Ways to build quality functionals in the description of the various processes are proposed. An example of product quality control at two consecutive stages of manufacture is given.
Applied Mathematics and Control Sciences. 2016;(3):79-98
| |