Bishkek, Kyrgyzstan

Kyrgyz State Technical University

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Jainakov A.,Kyrgyz State Technical University | Sultangazieva R.,Kyrgyz State Technical University | Medralieva B.,Kyrgyz State Technical University
CEUR Workshop Proceedings | Year: 2017

The mathematical model, which takes into account the effects of the Fe vapours in the arc welding of stainless steel workpieces in closed volume are proposed. The physical phenomena in arc plasma and molten pool are considered in coupled unified MHD model. The system is solved in the variables vorticity-stream function for five variables: stream function, vorticity, current function, enthalpy and metal vapour concentration. The system of equations solved by the finite difference method on a rectangular non-uniform orthogonal grid using the five-point difference scheme.The effect of metal vapour from weld pool on the characteristics of the arc column was numerically investigated. Distribution of electric field, current density and temperature field in the arc column and weld pool with and without consideration of the Fe vapor are shown.


Engel'sht V.S.,National Academy of science of Kyrgyz Republic | Muratalieva V.Z.,Kyrgyz State Technical University
High Temperature | Year: 2017

The thermal transformation of the pyrolysis–condensation–rankinite synthesis process at a normal pressure is considered in detail. Rankinite pyrolysis is performed with a step-by-step increase in enthalpy (TERRA software system). Rankinite pyrolysis components condense on a surface with temperature Т = 298.15 K. Condensate components are equivalent to pyrolysis components. Wollastonite and limestone can precipitate upon condensation to form a mineral deposit. Synthesis is performed by mixing the condensate components. The components and heat of chemical reactions, the enthalpy, the temperature, and the heat content are determined. It is shown that the decomposition of rankinite (Тdec = 2598.36 K), wollastonite (Тdec = 3662.7 K), and limestone (Тdec = 3680–3810 K) occurs in the process of synthesis and pyrolysis at a constant temperature. The complete pyrolysis–condensation–synthesis process picture typical for various compounds is given. © 2017, Pleiades Publishing, Ltd.


Bochkarev I.V.,Kyrgyz State Technical University | Khramshin R.R.,Magnitogorsk State Technical University
Procedia Engineering | Year: 2016

Development of the device for diagnostics of electromechanical friction brakes is relevant due to a wide application of the latter in the robotics industry, machine tool, lift and carry machine and aircraft building as well as various automated systems and process facilities. The paper specifies advantages and disadvantages of the known contact and non-contact methods of control of friction electromagnetic permanent magnet devices. It proposes a simple technical solution for control of friction electromagnetic permanent magnet devices. It peculiarity is in change of electric impedance of the controlled circuit that considers a closed and opened state of the disk armature as well as external and internal poles of the coil flux guide of electromechanical friction brakes. To improve operational performance of the device for control of the permanent magnet friction brakes, a complex of researches has been carried out based on which its most sustainable scheme has been obtained. It does not require complicated circuits for protection against false triggering. © 2016 The Authors. Published by Elsevier Ltd.


Usubamatov R.,Kyrgyz State Technical University | Sartov T.,Kyrgyz State Technical University
International Journal of Advanced Manufacturing Technology | Year: 2017

Automated production lines with high productivity are represented the complex and expensive systems based on mechanical, electric and electronic units, while predicting the efficiency of the automated lines is an important analytical task. Calculating the productivity rate of the automated production serial line (APSL) segmented on sections with embedded buffers of limited capacity is a complex and crucial problem for manufacturers. The productivity rate of APSL with balanced technological processes depends on the reliability of mechanism, workstations, transport and other units. Balancing the machining time leads to an increase in the number of workstations and in productivity rate of APSL. It also leads to an increase in the failure rates and hence to deceasing in the productivity rate of the production line. Solution for enhancing productivity is presented in terms of segmenting of APSL into sections with embedded buffers. This paper represents an analytical solution for the productivity rate of APSL segmented on sections with embedded buffers of limited capacity. The mathematical model for the productivity rate of APSL is derived as a function of the technological parameters, the capacity of the buffers and the number of stations and sections with different failure rates and cycle times. © 2017 Springer-Verlag London


Abdiraimov A.,Kyrgyz State Technical University | Gebel E.,Omsk State Technical University
2015 IFToMM World Congress Proceedings, IFToMM 2015 | Year: 2015

The article deals with spatial slider-crank mechanisms. The proposed method of the computer aided kinematic analysis is based on the principles of analytic algebra, geometry and trigonometry; therefor the displacement, velocity and acceleration of the output lever will be derived as a generalized coordinate function in the explicit form. The modifications of the spatial slider-crank mechanism differ from each other in the mutual location of the axes of the input and output links. The problems of the direct and inverse kinematics as well as the problem of identification of the restrictions on free kinematical parameters are solved. Numerical experiment has confirmed the validity and correctness of the theoretical results.


Zhainakov A.Z.,Kyrgyz State Technical University | Kurbanaliev A.Y.,Kyzyl Kiysk Humanitarian Pedagogic Institute of the Batken State University
Thermophysics and Aeromechanics | Year: 2013

The work presents the results of mathematical modeling of large-scale flows in areas with a complex topographic relief. The Reynolds-averaged Navier-Stokes equations constitute the basis of the three-dimensional unsteady modelling. The well-known Volume of Fluid method implemented in the solver interFoam of the open package OpenFOAM 1.7.1 is used to track the free-boundary location. The mathematical model adequacy is checked by comparing with experimental data. The efficiency of the applied technology is illustrated by the example of modeling the breakthrough of the dams of the Andijan (Uzbekistan) and Papan (near the Osh town, Kyrgyzstan) reservoirs. © 2013 Pleiades Publishing, Ltd.


Engel'Sht V.S.,Jeenbayev Institute Of Physical Technological Problems And Materials Science Chui Pr 265 | Muratalieva V.Z.,Kyrgyz State Technical University
High Temperature | Year: 2013

Thermodynamic analysis is performed (TERRA software) of the lime-silica interaction for all possible lime-to-silica ratios at normal pressure. The components of the exothermal reactions are calculated. The adiabatic temperature of silica combustion in the lime is found. The heat of the chemical reaction is determined. The enthalpies of the initial rough material and the combustion materials are calculated. The evolution of the silica combusting in the lime, including formation of the stochiometric glass, wollastonite, rankinite, and pseudo-cement, is considered. The thermodynamic analysis is performed under the supposition of use of chemically pure substances with the absence of external heat and specific additions. © 2013 Pleiades Publishing, Ltd.


Duishenaliev T.,Kyrgyz State Technical University | Askarbekov R.,Czech University of Life Sciences
Engineering for Rural Development | Year: 2016

In solid mechanics, there are classical methods for determining and calculating the deformation of the material body, which is used today. Such material, like rubber is anisotropic and at large deformations classical equations and relations are not applicable. For calculation of large deformations notion nonlinearity exists. The given paper contains the use of a non-traditional method for calculating the stress-strain state of rubber metal supports. This method is based on the Cauchy tensor to determine deformation of the body when there is displacement of the body points. With the help of Matlab system we wanted to show the applicability of the new method for calculation of the body with large deformations.


Engelsht V.S.,Institute of Physical and Technical Problems and Material Science NAS KR | Muratalieva V.Z.,Kyrgyz State Technical University
Thermophysics and Aeromechanics | Year: 2015

The authors have studied the change in the component composition of wollastonite marble from Slyudyanka deposits at increasing pressure (p = 0.1–12000 MPa) and temperature (T = 300–6000 K). Metamorphism of marble maturation has been found. The essence of maturation is the calcite melting, carbon dioxide deposition, the monolith compaction, the transformation of mineral composition at pressure increase up to the value of the initial components. When the pressure value reaches 12000 MPa the original components are reproduced, and the maturation of marble completes. Thermodynamic analysis reveals the secrets of the marble origin. © 2015, Pleiades Publishing, Ltd.


Bochkarev I.V.,Kyrgyz State Technical University
Procedia Engineering | Year: 2015

The investigation of a doubly fed induction motor in electric drives of pumping stations is conducted in this paper. The effect of non-sinusoidal rotor supply is considered in the analysis as well. The current total harmonic distortion (THD) is evaluated with respect to the selected voltage modulation in a thyristor frequency converter (TFC) as well as on motor duty cycle. A novel method of reactive power regulation with constant rotor current I2=I2H=constant is proposed. It is shown that the proposed method considerably improves motor performance in the whole operation range. The proposed analytical method is verified with laboratory measurements. © 2015 Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license.

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