Vol 26, No 1 (2018)

Articles
Two-channel time-optimal control of the process of nonstationary heat conductivity
Rapoport E.Y., Ilina N.A.
Abstract
Proposedformulationandthemethodofsolutionoftheproblemoftime-optimalcontroloftemperaturefieldof an infinite slabwithtwo boundary control actions by the value of the external heat flux on its surfaces in conditions of a given accuracy of uniform approximation of the final temperature distribution of the thickness of the slab to a given one is proposed. The proposed method uses the procedure of preliminary parametrization of control actions based on analytical conditions of optimality, subsequent reduction to a special problem of mathematical programming and methods of its solution based on the alternance properties of the desired parametrical characteristics and knowledge of physical regularities of the subject area. The results and their analysis for different variants of the resulting temperature distribution curve are given.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):7-17
views
Fuzzy optimization in the problems of forklift path planning
Rogachev G.N., Rogachev N.G.
Abstract
The procedure of fuzzy optimization as the problem of robotic forklift path planning in the changing environment for a number of typical situations differing in the goals of the forklift functioning and the constraints imposed both on control resources and on the forkliftbehavioris considered. Simultaneously with the construction of forklift paths, the synthesis of algorithms for the work of digital controllers of forklift control systems as hybrid continuous-discrete systems is carried out. The procedure for constructing control systems with fuzzy goals and constraints is based on the representation of control algorithms in the form of a priori non-fixed and time-variable systems of rules
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):18-30
views
Comparative analysis the efficiency of CRM for companies
Rybakova I.A., Orlov S.P.
Abstract
The paper deals with the problem of functioning evaluation of complex structured objects. It is proposed to use a nonparametric Data Envelopment Analysismethod. Quantitative performance indicators for complex objects are formulated, these indicators not being expressed in monetary units. The solution of the fractional linear programming problem is solved, which determines the practical efficiency frontier on the basis of the selected limited set of object input and output variables. The proposed technique is used to assess the effectiveness of the implementation of customer relationship management (CRM) systems at a number of companies. The analysis of the location of the estimated objects in space of the input and output parameters on the practical efficiency frontier was carried out. As a result, it became possible to identify priority areas for optimizing company’s resources on a limited budget.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):31-37
views
About the functionality of the specialized software of the account of movement of the mass of oil products in commodity and raw merchant parks
Trufanov Y.S.
Abstract
The list and description of the functional of the specialized software for recording of the oil productsmovement in commodity and raw parks are considered. Effective methods of organizing an interface for the users' work in this software, based on the experience of implementing it at the oil refineryare suggested. Control procedures and corresponding options for linking the objects of the company's balance sheet schemes for the operational control of the quantities of petroleum products recorded in the commodity and raw park are given.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):38-46
views
Sampling errors estimation in the determination of codes extreme values in systems for measurements of radial clearances in compressors of turbomachines
Belopukhov V.N., Borovik S.Y., Podlipnov P.E.
Abstract
The analysis of random errors caused by discrete character of information from the single-coil eddy-current sensor in systems for measurements of radial clearances in compressors of turbo machines is provided. For the specified errors the distribution law of probabilities is received and the main statistical characteristics are defined. On the basis of this results the technique of assessment of computing resources of the measuring system is offered. For the given accuracy of restoration of an extremum of ADC codes on an output on condition of maintaining constant frequency of sampling in all range of changes of rotational speeds of a rotor of the turbomachine and invariable volume of a buffer memory, the algorithm of decimation of codes is offered and its parameters are determined.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):47-54
views
Development of method and software for determining the size of grain of aluminum
Bochkarev A.V., Zobnin P.Y., Yaroslavkina E.E.
Abstract
The paper considers a technique for obtaining informative data from the acoustic emission signal measured during the crystallization of deformed aluminum alloys. The need for introduction of this method to enterprises, the urgency of the problem of the lack of operational control of the grain size and the mechanical properties of billets from aluminum deformable alloys is described. The most significant algorithms for analyzing acoustic emission signals are identified, and the choice necessary for implementation is made. A block diagram of the required algorithms is formed, a description of the individual blocks is given. The necessary corrections are indicated for the possibility of implementing the generated algorithms in the form of a program on an analog-to-digital converter with an integrated digital signal processor. An example of testing the received software for processing a random signal is given.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):55-60
views
Rational frequencies of rotors rotation detection for the minimize their radial runout
Gasparov E.S., Petrunin V.I.
Abstract
An experimental stand to influence the rotor and to obtain its reactions in the form of vibration acceleration signals with the method of testing was developed. Using modern hardware, the information-measuring system for the stand was developed. The vibration acceleration signals were obtained when exposed to the rotor assembly unit at the anterior and posterior supports and along the middle part of the body unit, which became the result of the experimental search for the control capable diagnostic points. The experiment proved that the point on the front support of the body unit is control capable. The validity of using the criterion in the form of the relative peak frequency for determining the value of the preload of the assembly unit supports at exposition in the area of the front support is shown.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):61-67
views
Determination of quantities and sizes of solid particles in the oil flow on the basis of ultrasound method
Lange P.K., Pautova A.S.
Abstract
We consider an ultrasonic system that records the presence of impurity particles in an oil flow and estimates their dimensions. The structure of a measuring system containing a matrix of emitting and receiving piezo elements forming a set of ultrasonic beams scanning the entire cross section of an oil pipeline is described. Experimental data on the parameters of solid particles in the oil flow are presented, an ultrasonic method for determining these parameters is proposed. Parameters of particles in the oil flow recorded by the described system are estimated. The ultrasonic signal model in the system under consideration is determined, the possibility of determining the size and amount of solid particles of minerals, as well as paraffins in the oil flow in the oil pipeline, is shown. An approximation model of the ultrasonic signal in the measuring system is proposed, the possibility of using such a system in the oil industry is determined.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):68-76
views
Energy efficiency of the generator of the wind power engineering unit in the conditions of changing rate of rotation
Anufriev A.S., Makarichev Y.A., Zubkov Y.V.
Abstract
The main share in the annual electricity generation wind farms provide during the periods when the wind speed exceeds 8 m/s. Therefore, when designing a synchronous generator of wind power plants, it is necessary to provide maximum efficiency for rotor rotation frequencies corresponding to such values of wind speed. In the generators of wind turbines or micro hydroelectric power stations, it is not advisable to observe the known ratio of equality of constant and variable losses, which ensures the maximum efficiency in the nominal conditions. To increase the energy efficiency of the unit, the generator should be designed so that the maximum efficiency point is shifted to the zone of maximum loads and rotation frequencies - to the right of the nominal point
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):77-82
views
Development of a mathematical model of an electrotechnical complex of nodal substation and obtaining the main analytical dependences
Goldstein V.G., Nurbosynov D.N., Tabachnikova T.V.
Abstract
Mathematical model to power load node including electro technical complexes field substation, tie-station and power distribution network of district substation is developed. Analytical dependences for voltage loss in function dependent and independent to variable parameters supply network and power distribution network in steady-state mode are received, computational method of voltage loss, which allows to determine optimal (rational) voltage level in main substation is developed. The offered computational method of voltage loss can make calculations for average parameters to object of a research or current parameters in real time, that reduces labor input when performing calculating and increases reliability in obtaining results. When using the current parameters in real time calculations are carried out simultaneously at all hierarchical levels of electrical power supply system on oil and gas extraction complex.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):83-91
views
Multisectional installation of indirectinduction heating of the liquid
Danilushkin A.I., Krivosheev V.E., Vasiliev I.V.
Abstract
The paper deals with the design of a high-performance induction plant for heating viscous liquids when pumping through pipelines. Specific features of the technological process of transportation of viscous liquids through pipelines are noted. A new device built into the heater line is proposed, which makes it possible to reduce the overall length of the heatersignificantly. The device is made on the basis of a three-phase inductor with a rotating magnetic field. The device provides simultaneous mixing and heating of the liquid flow while passing through the heater. The results of numerical computation of electromagnetic and thermal fields in the "inductor-metal cylinder-hollow rotor-liquid" system are presented. It is shown that the use of the proposed device makes it possible to shorten the length of the heater by 40 ÷ 50%. The results of the studies are intended to solve the problems of calculating the optimal design and operation parameters of a multi-section heater.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):92-101
views
Devices for protection of high-voltageelectric equipment with voltage 6 (10) kV from powerful electromagnetic exposurES
Fominich E.N., Revyakina E.V., Kolesnik I.V., Kuryakov E.V.
Abstract
The effect of powerful electromagnetic pulses of artificial origin on the electrical equipment of power supply systems (SES) is analyzed and it is shown that these effects pose a danger for power supply systems of 6 (10) kV. To protect the SES from induced impulse currents and voltages, it is necessary to use special hardware protectors with increased energy intensity and operating speed in comparison with conventional lightning protection. New types of protection devices of SES 6 ... 10 kV are considered, their circuit solutions, parameters and results of experimental studies are shown, which showed high efficiency of application of these devices for protection of electrical equipment of SES 6...10 kV.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):102-107
views
Calculation of heat losses in the underground laying of pipelines
Branfileva A.N., Eremin A.V., Gabdushev R.Z., Demkova E.M.
Abstract
It is the results of calculations of two types of underground laying of pipelines of heating networks laid in concrete (foam concrete) boxes. The first type is pipelines with applying thermal insulation on the surface of the pipe (concrete boxes). The second type is pipelines without this insulation (foam concrete boxes). Sincetheairlayerbetweenthepipeandtheshells of the boxes practically does not affect to the heat losses to the ground due to intensive convective heat transfer, we propose to reduce the dimensions of foam concrete rectangular boxes to the size of the pipe diameter. It will lead to significant (up to 50%) reduction in heat losses to the ground due to a much lower coefficient of thermal conductivity of the foam concrete compared to concrete as well as a smaller area of heat exchange with the soil. Inaddition, theweightofthestructure, itsdimensionsandcostare reducing.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):108-116
views
Gas-cooler installation for compressor shops of the maigas pipelines
Sheludko L.P., Gulina S.A., Goryunova I.Y., Vlasov G.V.
Abstract
Questions of reliability augmentation and efficiency of technological processes of compressor stations of the main gas pipelines using gas-cooling installation of new type are considered. The carried-out assessment of efficiency of use of air coolers of natural gas which showed that during a summer time frame the efficiency of this equipment decreases. Thermodynamic calculation of gas-cooling installation is carried out, and are defined thermodynamic by evaporator parameters, providing the given temperature of technological gas on an input in the trunk. As temperature of the cooling water does not depend on ambient air temperature, and is defined by thermodynamic parameters of the evaporator, it gives the chance of obtaining the given, stable temperature of technological gas for submission it in the trunk. Stabilizing of temperature condition throughout the main gas pipeline will allow to reduce the capacities spent for increase in pressure in TsN. Increase in power of the turbine jet during the summer period after moistening of air on an input in the compressor is calculated.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):117-127
views
Phase equilibrium for Pb-Sb-Sn alloy during vacuum distillation
Korolev A.A., Krayukhin S.A., Maltsev G.I.
Abstract
In the temperature range 823-1073 K for Sn-Sb and Pb-Sb alloys the calculated steam pressure (Pa) for Sb (3.95-273.66), Pb (2.63.10-4-14.86.10-2) and Sn (3.32.10-9-8.12.10-5). High values of the ratio (p*Sb / p*Pb) .103 = 15.04-1.83 and p*Sb / p*Sn = 1.19.109-3.37.106 create a theoretical background for sequential selective separation of these metals by vacuum distillation, when the antimony, and then the lead is enriched in the gas phase, and tin - liquid. Phase diagrams for VLE (vapor liquid equilibrium), can be used the lever rule (rule lines) to help predict quantities of substances, residues and sublimates at a predetermined temperature. When calculating the parameters of the ternary alloy according to the equation of Wilson is enough to use the parameters obtained for binary systems. Equity is defined the free Gibbs energy, kJ/mol (-ΔGPb/Sb/Sn = 13.8-42.6/2.6-15.1/2.1-26.4), enthalpy, j/mol [±ΔНPb/Sb/Sn = (1.3-70.2)/(1.56-107.1)/(2.8-48.5)] and entropy,j/K.mol (ΔSPb/Sb/Sn = 15.8-25.0/3.0-17.4/2.4-15.8) for components in the Pb-Sb-Sn melts. Increasing the share of metals in the initial alloy of the magnitude of the Gibbs free energy decrease.Negative and positive values of enthalpy indicate the exothermic and endothermic nature of the processes in the melt by distillation of the components. Shown satisfactory correspondence between calculated and experimental values of thermodynamic parameters: average relative deviation of 1.9 % ; the standard deviation of 0.1 kJ/mol.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):128-140
views
The measurement of a thin crystal structure of minerals
Peskov A.V., Tarasova E.Y.
Abstract
The results of calculations of the sizes of areas of coherent scattering and the values of the microscopic strains of a method of approximation for a number of rock-forming minerals. The comparison of the two methods of analysis of the microstructure - expressive method, the FWHM of the profiles are approximated by Voigt function and analyze the shape of the profile of the diffraction lines taking into account the asymmetry of hardware distortion and physical profile. Experimental justification of the choice of the analytical lines of the investigated mineral and standard to improve the accuracy of the definitions. Method of determination of parameters of defects of the crystalline structure of the minerals tested in the operation of the equipment with the specified Express and precision.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):141-148
views
The research of the spatial-temporal influence of heterogeneity creep deformation on the relaxation residual stresses in the surface-hardened hollow cylinder of D16T alloy
Radchenko V.P., Liberman A.E., Ruzov A.V.
Abstract
We studied the influence of a stochastic heterogeneous creep deformation on the relaxation residual stresses in the surface-hardened hollow cylinder of D16T alloy at a temperature of 125 C degrees. The surface is hardened by the air shot-peening under monoaxial tension. We have shown experimental data of local creep deformation distribution on spatial coordinate with the base of 6 mm at a length of working part of the specimen of 65 mm. We found a variation of the strains in the local sections of a specimen which strain may differ from each other by three or four times. The stochastic rheological straining determining equations with two random parameters are suggested. The parameters define individual straining properties of the local sections. The method for identification the parameters is developed. The relaxation of residual stresses in every local section taking into account define individual creep straining properties under four modes of tension stresses is studied. We observe, velocities of the relaxation residual stresses in the local sections may differ from each other by 2 or more time as a consequence of creep. Several recommendations for estimating the resource of hardened specimens under the creep conditions taking into account define individual straining properties on spatial coordinate.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):149-163
views
The efficient design of inductors
Zimin L.S., Leonenko A.S.
Abstract
The problem of achievement of the maximum energy efficiency of technological complexes "induction heating installation (IHI) - metal processing by pressure" is considered. The emphasis during optimization of induction heating installation is directed on parameters of the deforming equipment (a press, a rolling mill, etc.). The characteristics of the induction heating of rectangular bodies, for example, the slab for rolling is analyzed. Here, in contrast to the heating of cylindrical billets, thermal and electrodynamic problems arise. This is, above all, the appearance of the longitudinal as well as the transverse edge effect, i.e. the appearance of temperature gradients along the cross-section perimeter. Electrodynamic vibration and accompanying noise, in excess of health standards for shopfloor belong to electrodynamic problems
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):164-167
views
Application of the mir pia software for computer modeling of oil separation systems
Ivanyakov S.V., Kryuchkov D.A.
Abstract
The problem of carrying out technological calculations for oil separation systems in oil fields is considered. The use of the MiRPiA software for mathematical modeling of oil separation systems is proposed. Comparison of the calculation accuracy of the Mir PiA software with the software products Aspen Technologies HYSYS and Invensys Process Systems PRO/II is made. The correspondence of the obtained calculations to the experimental data of single degassing of oils with various gas factors is revealed.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):168-172
views
Chemical analysis of the magnesium alloy corrosion destruction
Katz N.G.
Abstract
The problems of the corrosion products formation on the tread alloy surface after the five-year exploitation in the bottom water are considered. Quality laboratory research of the tread alloy chemical destruction to determine the ion composition of the corrosion products is carried out. The tread alloy photos with the destruction areas are presented. The analysis of corrosion products is made; probable causes of their formation are described. Qualitative techniques of the chemical analysis of the tread alloy corrosion destruction are presented. The conclusion of the further possibility or impossibility of itsproduction is made
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):173-176
views
Automated testing system for the database contains the components thermophysical properties
Konygin S.B., Konovalenko D.V.
Abstract
The paper deals with the problems of automated testing system of database according to the thermophysical properties of chemicals. An offered set of simple criteria allows to decrease the errors in constant and temperature-dependent parameters of chemicals. This system was realized in the program platform for modeling and calculation of the processes and devices (“MiRPiA”). The testing of this system showed the feasibility of its use. Some errors can occur on the acentric factor for the light chemicals. The assessment of the standard liquid density for the heavy hydrocarbons is problematic.
Vestnik of Samara State Technical University. Technical Sciences Series. 2018;26(1):177-180
views

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies