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A mathematical model of thermal processes (dynamic) contact current collector with contact suspension (in motion), which allows to estimate the temperature distribution of heating the current collector during movement. The experimental evaluation of the proposed cooling device performance is given. The thermal model of the current collector in motion mode has been verified.

The subject of research is the evaluation of the effectiveness of different modes of energy-optimal control of the movement of a freight train of a unified mass by AC freight electric locomotives of the Uz-El series with asynchronous electric motors on the flat section of Kokand - Andijan of the Uzbek railway. Purpose of the study: substantiation of the main performance indicators of electric traction locomotives, taking into account the given traffic schedule, using various options for the optimal mode of controlling the movement of a freight train with a unified train mass on a real flat section of the Uzbek railway. The methods and methodology of the research are the theoretical foundations of locomotive traction, the mathematical theory of optimal object control, as well as the C # programming language (C Sharp) with the development of mock-up applications in the Microsoft Visual Studio 12.0 programming environment.As a result of the study, energy-optimal curves, kinematic parameters of the movement of a freight train and parameters of the main indicators of the energy efficiency of the investigated electric locomotive for different options for traction calculation on the real flat section of Kokand - Andijan of the Uzbek railway were obtained. The obtained kinematic parameters of the movement of freight trains with a unified mass of the train and the parameters of the efficiency indicators for the use of the studied electric locomotives can be used in the Kokand locomotive depot, which will allow developing regime maps for driving freight trains by these electric locomotives, depending on the level of complexity of the track profile and various conditions for organizing rail transportation of goods.

In this paper, the possibility of controlled shunt reactor (CSR) to absorb excess charging capacity in long lightly loaded transmission lines of 110 kV electric networks Nordic branch of JSC "IDGC of Siberia" - "Omskenergo." The emergence of excess reactive power leads to an increase in the voltage at the nodes of the power system and the emergence of significant power loss. The application of CSR, The calculation of the required power, the place of installation, pre-feasibility study.

A study of the influence of non-linear parameters spring of a freight car suspension (stiffness spring, length base of a bogie, roughnesses railway) on the amplitude and phase fluctuations bouncing body is completed. Defined own vibrational frequency jumps car body as a function of the parameters.

Analysis of the causes of errors of measurement of phase shifts of harmonic components in electrical railway traction networks and describes how to improve the accuracy of measurement.

The article sets the task of determining the level of dynamic loading in the «trolley-leash-traction motor» subsystem to reduce the dynamic impact in the «locomotive-path» system. The model of vertical vibrations of traction rolling stock, obtained on the basis of the Lagrange equation of the second kind, in the form of a system of fourteen differential equations allows us to estimate the loading of locomotive units in operation, integrated using the MathCAD application package. The approximation of random disturbances using the spectral density of the path irregularity of Professor A. I. Belyaev is chosen as the spectral density of random disturbances. A more detailed design scheme of the crew has been compiled and in order to simplify the calculation within the engineering error, a single-mass discrete model of the path is used. Entering symmetric coordinates allows us to obtain from the original system of differential equations a simplified system with characteristic equations with simple roots, therefore, the natural oscillation frequencies of the bouncing of the body, trolley and wheelset will be determined with minimal error. The transfer function is determined by Kramer's formulas. With the help of a computer, the values are calculated and graphs of the amplitude-frequency characteristics of vertical movements, maximum accelerations of the body, trolley, traction motor and wheelset of the electric locomotive in question are constructed. A comparative analysis of the calculation results and empirical data is carried out. Based on a comparative analysis, it can be argued that the considered mathematical model of vibrations of the electric locomotive 2ES6 «Sinara» is adequate and allows determining the dynamic loading of the locomotive for the entire range of operating speeds. The task of changing the existing design of the suspension system of the traction electric motor of the electric locomotive in question and the mathematical analysis of the vibrations of its nodes in further research is set.

The article presents the equivalent circuit of three conductors, taking into account their mutual influence. The equivalent circuit contains the resistance and inductance of each conductor, the conductivity and the capacitance of their insulation relative to the earth, as well as the mutual inductances, conductivities and capacitances of the insulation between the conductors. The mathematical foundations of calculating the distribution of electrical quantities in the system of three conductors are considered, taking into account their mutual influence. An iterative incremental model of the software life cycle was chosen as the basis for automating this calculation, taking into account existing approaches to software development. Specific features of specialized software are specified. A structural scheme of the software complex and a block diagram of the calculation algorithm are proposed. The algorithm is based on the iterative calculation of currents and voltages for three conductors, taking into account their mutual influence. In accordance with the chosen model of the life cycle of the software, three versions of software with different functionality have been developed. This allowed us to effectively organize the processes of testing, debugging and implementation. As a result, the software complex has a window interface containing four tabs and allowing to enter the initial data for the calculation, display the results in the form of graphs and tables. For saving the results of calculations, a connection with the database has been implemented.

Researching subject which are presented in article is the emergency modes in 25 kV traction power supply systems caused by the short circuits (SC). The research purpose consisted in the analysis of calculation SC currents errors evolving from the reactances determined by SC power at the simplified modeling of external network. For achievement of formulated purpose comparative calculations of SC currents for a number of standard schemes of 25 kV system when using full models in phase coordinates and with use of simplified electric power system (EPS) reactances are executed. Modeling has shown that calculations of SC currents of contact network of deadlock substation by EPS reactances give the acceptable accuracy for feeder current of substation near which there is a short circuit. The calculation error of remote substation feeder current can reach +100% at SC power on inputs of substation about 300 MV·A, but decrease to values about 10% at the SC power of 2500 … 3000 MV·A. At food of group of traction substations from two 110 kV lines calculation error for equivalent reactances it is much less, however at SC power about 300 MV·A errors reach 35% and decrease to 10% at SC power on substation inputs more than 550 MV·A. Variant of traction substations power supply from two 220 kV power lines differs in small calculation errors of SC currents for equivalent external power supply reactances: differences from full scheme don't exceed 9% at SC powers of 1200 MV·A or more. The received results can be used at improvement existing and creation of new definition techniques for SC currents in 25 kV traction networks.

The work is devoted to the consideration of the possibility of using composite materials with an aluminum matrix in the design of electric transport pantographs. Currently, there is a tendency to increase the speeds of electric transport. This fact requires reliable and high-quality current collection, which can be achieved by reducing the mass of the current collector design, including through the use of composite materials. The possibility of using composite materials in parts and assemblies of current collectors operating under conditions of increased current loads and at high speeds of movement and the mechanical characteristics of the traditional ones used in the carriage design and the composite materials proposed for use are analyzed. The design of a carriage of high-speed electric rolling stock has been developed, in which an aluminum matrix composite material was used as a structural material. Statistical modeling using the finite element method in the SOLIDWORKS Simulation software package was performed. Comparison of the strength characteristics of carriage assemblies made of traditional materials and aluminum matrix composite showed the possibility of reducing their weight in the case of composite use without reducing the strength of structural elements. The static characteristic of the carriage in which the composite material was used coincides with the static characteristic of the carriage made of traditional materials, which confirms the possibility of using an aluminum matrix composite without making significant changes to the carriage design. To evaluate the dynamic characteristics of the composite carriage and its effect on the dynamic characteristics of the pantograph, modeling was carried out using the methods of multibody modeling of SOLIDWORKS Motion. The obtained simulation results indicate an improvement in dynamic characteristics when using composite materials, which has a beneficial effect on the reliability and quality of current collection.

The problem of the assessment of the continuous welded rail track stability at its thermal elongation is considered in this paper. The method for determining the stress-strain state of various elastic objects developed by the specialists of JSC “VNIKTI” is analyzed on the example of a rail of a continuous-welded track section. The essence of the method is to determine the dependence of the natural frequencies of rail vibrations on the applied longitudinal force. As a means of obtaining such a dependence, a modal analysis of a track section model carried out using the finite element method was chosen. The methodology for calculating the natural frequencies of rail vibrations and the description of the created model of the track section and its properties are presented in the paper, the contact interactions of the model elements and boundary conditions are defined in it. Calculations for determining the natural frequencies and modes of rail vibrations are performed, the first four modes of rail vibrations obtained by calculation and experimental methods are shown. The assessment of the adequacy of the created model of the track section is carried out by comparing the natural frequencies and modes of rail vibrations obtained by calculation, by modal analysis methods and experimentally when measuring vibrations on a full-scale object - assembled rails and sleepers, having a similar design compared with the model. It was decided to use the distance between the vibration nodes as a criterion for comparing the obtained modes of natural rail vibrations. The first mode of vibration is selected for further studies. Calculations were carried out and the dependence of the natural frequency of the first vibration mode of the rail on the longitudinal force applied to it was obtained using the created model of the track section. The obtained dependence can be used in the method proposed by the specialists of JSC “VNIKTI” in order to determine longitudinal force, applied to the rails on the full-scale section of the continuous welded rail track.

The analysis of wave processes in the system including electric transmission lines, traction substations, AC traction network and electriclocomotives is necessary to accurately assess to energy performance of its work. This system contains concentrated and distributed parameters, consequently the analysis of such a system is difficult and the rolling stock which is also a part of this system represents a dynamic load. The proposed mathematical model of the alternating current traction power supply system allows us to consider electromagnetic processes at its various points taking into account wave processes.

The paper considers the influence of the force characteristics of the damping apparatus on the value of the maximal longitudinal forces arising between the cars. Using the computer program MSC.ADAMS, we performed the simulation of shunting collisions of cars and train transient movement modes. The dependences of the maximal forces at cars' collision at various velocities on the shape of the elastic elements' force characteristics are determined. The operation of various shock dampers for the case of the train starting off electric braking and movement through the parts of the longitudinal track profile was estimated. It is shown that shock dampers with a rapidly growing line of load lead to the emergence and propagation of large shock forces along the train, while a slow growth of the force leads to their reduction due to the amplitude increase in elastic vibrations propagated along the train length . We propose to use high-energy-damping devices to reduce the longitudinal forces in the train, which are characterized by the force slew rate substantially depending on the compression velocity of the shock damper.

Shotcrete lining is one of the most common types of temporary supports in tunnel construction. The influence of shotcrete lining on design calculations of permanent lining is difficult, because there is no method of designing at the present time. This leads to increasing in consumption of materials and labour of construction. The information about the influence of the basic mechanical properties of soils, geometrical size of construction per value of temporary shotcrete lining factor was obtained during research. These data formed the basis for futher development method of designing. Empirical correlations of stress distribution between temporary shotcrete lining and permanent monolithic reinforced concrete lining were obtained during theoretical research. Results of experimental research tensity of temporary shotcrete and permanent lining confirmed the possibility of using in the designing this empirical correlations. Using in the designing proposed empirical correlations will leads to reduction in consumption of materials and labour of construction.

One of the ways to increase the capacity of railways is to use long-distance freight trains with a distributed traction system. In order to reduce the influence of the human factor, it is advisable to use automatic speed control systems on the locomotives of such trains, that take into account the transients occurring in the train. Determination of the longitudinal forces that occur in the train can be carried out by using either a reference mathematical model of the train, or pre-calculated dependencies of these forces on the parameters of the train movement. The second method allows you to simplify the structure and improve the performance of automatic control systems.

The aim of the research presented in the article was to develop computer models for determining the electromagnetic fields (EMF) generated by three-phase 25 kV traction power supply systems (TPSS). In contrast to traditional single-phase TPSS, three-phase systems are electromagnetically balanced, provide symmetric loads of substations, increase voltages at current collectors of rolling stock, reduce asymmetry and non-sinusoidality in 110 - 220 kV supply networks. However, the issues of quantitative assessment of electromagnetic safety conditions in three-phase traction networks remain unstudied. To implement the formulated goal, we used the methods of modes and EMF simulation developed at the Irkutsk State University of Railway Transport, the distinctive feature of which is the use of phase coordinates; in this case, the models of TPSS elements are formed on the basis of lacelike equivalent networks. The simulation was carried out for three-phase TPSS schemes of different complexity, in which case the complex traction network was implemented by modifying the model of a real TPSS of one of the main railroads of Eastern Siberia. Simulation results indicated that compared to the typical TPSS 25 kV, the maximum electric field strength increases by 2.5 % in the three-phase system. The maximum value of the magnetic field strength decreases by 26 %. Similar indicators for average values are 2.6 and 19 %. The proposed methodology and the developed computer models can be used in the design of promising three-phase TPSS. In the conditions of power engineering digitization, the application of this technique in practice will allow to apply a scientifically validated approach to the analysis of electromagnetic safety conditions traction networks and to develop its improvement.

The algorithms and modeling program allowing estimating indicators of financial technological risk, based on a random process of dynamic risk.

The article is about defining corrosion state of overhead structures underground part. Specially designed concrete models are used for experiments and calculations. These models are made with the fabric technology of overhead structures creation. «Steel - Concrete» interface region parameters are calculated with a help of transient process which situated when DC power supply is connected to the scheme. There is a formulas and a methodic for calculation needed parameters. In the end of the article theoretical curve is located. It exactly coincides with an experimental curve.

Transportation in tank cars of viscous liquid cargo (fuel oil, paraffins, industrial oils, cracking residues, etc.) is difficult with their solidification, accompanied by a sharp increase in viscosity. In fact, this leads to the need to warm up or partially warm up the transported oil product before unloading, usually carried out as a gravity discharge, in order to restore the fluidity of the delivered oil cargo. The process of unloading in this case with heating leads to a significant increase in the cost of transporting petroleum products, including the downtime of tank cars, and in general, a decrease in the turnover of rolling stock. According to the analysis carried out to determine the costs of the technological process of heating frozen petroleum products transported by rail, about 600 thousand tons of conventional fuel are spent per year, and the idle time of tank cars under unloading and subsequent cleaning of boilers from high-viscosity residues of oil cargo exceeds 1 million car-hours. The urgency of the issue of reducing the cost of railway transportation of viscous cargo is due to the intensive development of the Northern and Eastern regions of the Russian Federation. Important factors for transportation in these conditions are not only the negative average daily air temperature, but also long distances. The issue of reducing the cost of transportation of viscous petroleum products at low air temperatures is considered. Viscous petroleum products, when thickened, turn into a rheological liquid, which does not have a clear interface between the liquid and solid phases. The methods of transfer to the stratified state of hot fuel oil during its slow cooling and partial solidification with the formation of a heat-insulating layer of solidified fuel oil are applied. The positive effect is achieved by reducing the time and cost of thermal energy for unloading the delivered oil product by reducing the rate of its cooling during transportation. This, in turn, is achieved by suppressing the natural convection of the hot oil product on the cold walls of the boiler of the tank car in the first few hours after filling the tank. From the comparison of the experimental data and the calculation results, the values of the empirical coefficients of the equation for the heat transfer coefficient of liquid petroleum products are selected. The standard deviation of the absolute temperature of the liquid petroleum product was 8 %.

The article deals with the issue of improving the energy efficiency of DC and AC electric locomotives operated at the enterprises of JSC “Russian Railways». The main goals and objectives of the development program and energy strategy of JSC «Russian Railways» are analyzed and briefly considered. In accordance with these tasks, the relevance of scientific research in the field of improving the energy efficiency of electric locomotives is substantiated. The current data on traction rolling stock, on modern traction resource management systems and on Russian and foreign scientific research in the field of energy efficiency are analyzed. As a result of the analysis, it was found that most of the studies are aimed at studying the influence of key operational factors on energy efficiency indicators, so, in this case, on the specific power consumption for train traction. However, the reverse question has been poorly studied - the selection of the train mass and the technical speed on the basis of a preliminary assessment of the specific power consumption for train traction by analyzing the statistical data of trips on a certain section of the railway. The purpose of this study is to assess the possibility and develop a method for determining the optimal values of the key parameters of the operation of electric freight locomotives in order to achieve maximum operational efficiency in relation to them according to the criterion of energy efficiency. Two models were created in the program «Complex of calculations of traction power supply» (CORTES) - for DC and AC electric locomotives, describing the dependence of the energy efficiency indicator (specific power consumption for train traction) on operational indicators, such as the train mass and the technical speed. The initial data for further modeling were obtained by modeling trips on a conditional site.

A significant share of JSCo «Russian Railways» expenses falls on the purchase of diesel fuel and electric power for train traction. In this connection, the task of ensuring rational consumption of energy resources acquires special importance. Its solution is impossible without a well-functioning system for planning and forecasting the energy efficiency of locomotives. The article proposes a method for predicting specific energy consumption (SEC) for train traction, based on determining predicted values of transportation work and fuel and energy resources consumption by extrapolating time series, which consists in spreading the trends in changes in the values established in the past to the future period. A distinctive features of the developed method is the determination of seasonality indices and consideration of the rhythm of changes in the indicators. In cases where the forecast period includes months of the first or fourth quarters, a formula is proposed for determining the forecast value of the SEC, taking into account the influence of the atmospheric air temperature. The calculations performed showed that the application of the proposed method for structural divisions with different volume and nature of transportation work and the level of the SEC ensures a sufficiently high accuracy of train traction energy cost forecasting. The method is included in the Methodology for Analysis and Prediction of Fuel and Energy Resources Consumption for Traction of Trains developed by OmGUPS and implemented in the railroad network of the Russian Federation.

Evaluation of fatigue life is based on the use of basic fatigue curves. However, due to large va-riety of possible design solutions basic fatigue curves cannot be calculated for all cases. In addi-tion, the production practice has a significant influence on the durability of structural elements. To predict the fatigue durability using the traditional method we need to consider the influence of structural and technological factors by introducing the correction coefficients established on the basis of the experience and accumulated experimental data. The correction coefficients are widely used in calculating the resource elements by domestic and foreign construction firms. Using the traditional method the match of the projected longevity and durability resulted in a bench test struc-tures are not always satisfactory. Often by conducting rapid analysis the sufficient fatigue curves absent, the closest in characteristics among the available are selected. The article presents the im-proved technique of numerical fatigue life prediction of structural elements by using the modified fatigue curves, considering the impact of structural and technological features of the products of the actual design. The results of calculated estimate of the resistance of fatigue thin-walled struc-tures and their comparison with experimental data are presented. On the basis of the work carried out was drawn the conclusion that by using the method of calculation of fatigue longevity using modified fatigue curves , considering the structural features fragments of products, the convergence of the results of predicting fatigue life and test bench results obtained higher than by using tradi-tional techniques.

The operational reliability of the electrification and power supply system and the associated traffic safety is mainly determined by the technical condition of the contact network-an element that is extremely difficult to reserve in any way. The state of the contact network devices of the East Siberian railway is indirectly characterized by periods of electrification of sections. The equipment of the contact network, put into operation in the 1960s and 1970s, has developed its design life, does not have the required load capacity enough and reduces the reliability of the electrified section. The article shows that the purpose of improving the reliability of electrical equipment in the operation of power supply devices is to predict the state of its elements, in particular the metal supports of the contact network, as an object of study. Correctly assess the state and resource of the contact network devices will allow the use of the latest diagnostic systems by personnel in practice, using mathematical apparatus and modeling methods. It is shown that by monitoring various parameters characterizing the support, it is possible to detect a change in the technical condition of the object of study in time and to carry out maintenance in the period of time when there are deviations of parameters beyond unacceptable limits. The statistical data on the state of the support economy at the VSZHD are summarized, the main types of damage to metal support and supporting structures are given. It is shown that new types of damage to metal structures, not classified earlier, are revealed, that qualitative and quantitative assessment of the state of metal supports of the contact network, which have various structural damage is possible using methods, modeling, simulation and evaluation of the state of structures. FEMAP, an independent computer-aided design system from Siemens PLM, is used as an independent full-featured environment for modeling, simulation and evaluation of the results of the analysis of the characteristics of metal supports of the M6/10 model

The article outlines the principles of quantitative evaluation of information security from the viewpoint of the theory of games. Definitions of the game matrix and its quantitative interpretation. Offered practically implemented method of analysis, planning and design of information security based on the proposed models.

The necessity of searching for new methods to improve the dynamic rationalized properties of the traction drive, which does not create contradictions between the conclusions based on the results of numerical parametric analysis and the results of the analysis of nonparametric factors, is established. A modified base point method is proposed that takes into account the possible presence of areas of conservatism of a rational parameter and provides for a procedure for checking for conservatism. The search results using this method for a rational version of a traction drive with a support-frame suspension of an electric motor and a gear reducer coincide with the empirical choice of different manufacturers of locomotives.

The analysis of functioning of difficult transport systems is provided in article, the basic principles of use of simulation modeling in the organization of transportation process on railway transport are characterized. The method of creation of object-oriented model for the description of dynamics of interaction of cargo station and a way of uncommon use is considered.