Science and Transport Progress

17-24

Authors: M. M. Biliaiev, M. O. Oladipo

Purpose. The article aims to develop 2D numerical models for the prediction of atmospheric pollution during transportation of coal in the railway car, as well as the ways to protect the environment and the areas near to the mainline from the dust emission due to the air injection installation. Methodology. To solve this problem there were developed numerical models based on the use of the equations of motion of an inviscid incompressible fluid and mass transfer. For the numerical integration of the transport equation of the pollutant the implicit alternating-triangular difference scheme was used. For numerical integration of the 2D equation for the velocity potential the method of total approximation was used. The developed numerical models are the basis of established software package. On the basis of the constructed numerical models it was carried out a computational experiment to assess the level of air pollution when transporting bulk cargo by rail when the railway car has the air injection. Findings. 2D numerical models that belong to the class «diagnostic models» were developed. These models take into account the main physical factors affecting the process of dispersion of dust pollution in the atmosphere during transportation of bulk cargo. The developed numerical models make it possible to calculate the dust loss process, taking into account the use of the air injection of the car. They require a small cost of the computer time during practical realization at the low and medium power machines. There were submitted computational calculations to determine pollutant concentrations and the formation of the zone of pollution near the train with bulk cargo in «microscale» scale taking into account the air curtains. Originality. 2D numerical models taking into account the relevant factors influencing the process of dispersion of pollutants in the atmosphere, and the formation of the zone of pollution during transportation of bulk cargo by rail were created. A way to protect the atmosphere from pollution during the emission of bulk cargoes from the rail car, which is based on the principle of the air injection, was developed. Practical value. The efficient numerical models which can be used in the development of environmental protection measures in the operation of railway transport were considered. The proposed model allows calculating 2D dynamics of wind flow, taking into account the installed air injection, and mass transfer process of pollutants in the atmosphere.

33-47

Authors: O. M. Pshinko, V. V. Skalozub

Purpose. The paper aims to develop rating models and related information technologies designed to resolve the tasks of strategic planning of the administrative and territorial units’ development, as well as the tasks of multi-criteria control of inhomogeneous multiparameter objects operation. Methodology. When solving problems of strategic planning of administrative and territorial development and heterogeneous classes management of objects under control, a set of agreed methods is used. Namely the multi-criteria properties analysis for objects of planning and management, diagnostics of the state parameters, forecasting and management of complex systems of different classes. Their states are estimated by sets of different quality indicators, as well as represented by the individual models of operation process. A new information technology is proposed and created to implement the strategic planning and management tasks. This technology uses the procedures for solving typical tasks, that are implemented in MS SQL Server. Findings. A new approach to develop models of analyze and management of complex systems classes based on the ratings has been proposed. Rating models development for analysis of multicriteria and multiparameter systems has been obtained. The management of these systems is performed on the base of parameters of the current and predicted state by non-uniform distribution of resources. The procedure of sensitivity analysis of the changes in the rating model of inhomogeneous distribution of resources parameters has been developed. The information technology of strategic planning and management of heterogeneous classes of objects based on the rating model has been created. Originality. This article proposes a new approach of the rating indicators’ using as a general model for strategic planning of the development and management of heterogeneous objects that can be characterized by the sets of parameters measured on different scales. At this the control of separate elements is realized by the way of individual mental models construction and application of functioning processes. The procedure for evaluating of the prediction reliability based on multivariate linear extrapolation method was proposed. Practical value. The proposed method of strategic planning of the complex systems’ development based on rating models and developed information technology are representing the complex of automated tools to ensure effective economical and technological control of non-uniform sets of multiparameter objects. The new solutions of typical tasks of strategic planning and development of complex objects management procedure are implemented in the information technology of rating estimation (rating definition, sensitivity analysis, clustering, diagnostics, forecasting, resource allocation, multi-criteria analysis etc.). Application of the proposed information technology can automate the task of analysis and strategic planning of the administrative-territorial complexes. The technology can be used for monitoring, analysis, strategic planning and management of several complex system types simultaneously.

61-68

Authors: S. A. Semenov, E. V. Mikhailov, O. H. Reidemeister

Purpose. The article is aimed to the definition of technical and economic efficiency from the use of wheels of perspective structural scheme in the undercarriage of the rail vehicles (wagon). Methodology. The use efficiency of wheels of promising design scheme by reducing the motion resistance and wear of the wheel flanges is estimated by calculated values of estimated annual economic effect of implementation and payback period of the costs required for the development and implementation of the proposed wheel. Non-recurring costs include the cost associated with conducting research and development work, as well as the additional costs required for the manufacture of wheels of promising design scheme. Findings. In the course of computation and analysis of the economic efficiency from introductions of wheels of promising design concept, carried out on the basis of the initial data for the South-West railway, it was determined the profit which can be obtained by reducing the following operating costs: cost of returning the wheel flange on wheel sets; cost of fuel and energy resources for train traction; the value of the idle of cars in the current uncoupling repair; cost of repairs and current maintenance of rail track. In addition, it can be additionally released a number of cars by reducing their downtime. The calculation of net discounted income is carried out with the following assumptions: calculation period; estimated increase in the cost of wheel sets with wheels of promising constructive scheme compared to the model, the values of net profit for the accounting period, which was calculated by calculating the average value minus the cost of research, development and manufacturing of wheelset park with wheels of new design scheme. For a given billing period, the calculated value of the net discounted income was obtained and the payback period of the project was determined. Originality. The approaches to the perfection of design scheme of wheels, used in running gear of railway vehicles were substantiated. Practical value. The calculation method proposed in this publication allows evaluating the technical and economic feasibility of using the wheels of promising design scheme in the running gears of railway vehicles.

79-87

Authors: O. S. Krasheninin, O. V. Klymenko, O. V. Ponomarenko

Purpose. The research work focuses on forecasting of performance evaluation of the tractive and non-tractive vehicles that will satisfy and meet the needs and requirements of the railway industry, which is constantly evolving. Methodology. Analysis of the technical condition of the existing fleet of rolling stock (tractive and non-tractive) of Ukrainian Railways shows a substantial reduction that occurs in connection with its moral and physical wear and tear, as well as insufficient and limited purchase of new units of the tractive and non-tractive rolling stock in the desired quantity. In this situation there is a necessity of search of the methods for determination of rolling stock technical characteristics. One of such urgent and effective measures is to conduct forecasting of the defining characteristics of the vehicles based on the processes of their reproduction in conditions of limited resources using a continuous exponential function. The function of the growth rate of the projected figure degree for the vehicle determines the logistic characteristic that with unlimited resources has the form of an exponent, and with low ones – that of a line. Findings. The data obtained according to the proposed method allowed determining the expected (future) value, that is the ratio of load to volume of the body for non-tractive rolling stock (gondola cars) and weight-to-power for tractive rolling stock, the degree of forecast reliability and the standard forecast error, which show high prediction accuracy for the completed procedure. As a result, this will allow estimating the required characteristics of vehicles in the forecast year with high accuracy. Originality. The concept of forecasting the characteristics of the vehicles for decision-making on the evaluation of their prospects was proposed. Practical value. The forecasting methodology will reliably determine the technical parameters of tractive and non-tractive rolling stock, which will meet the modern requirements of the railroading, including at the design stage and while upgrading the vehicles.

96-104

Authors: O. M. Darenskiy, Yu. L. Tuley, D. O. Potapov, A. S. Malishevskaya

Purpose. Despite the steady increase in the length of sections of continuous welded rail on concrete sleepers, wooden railway sleepers, as one of the options of under-rail bearings, are still operated on a sufficiently large number of areas, in particular, remain uncontested in the curve of up to 350m radius, as well as on the main ways of subways. The main types of fasteners in the most common types of intermediate rail fastenings for wooden sleepers are track screws and spikes. Since the «wheel-rail» system contact peculiarities existing in track curved sections have a significant impact on the processes of interaction between the railway track and rolling stock, it is necessary in this work to determine the rigidity of the track screws and spikes, which are directly involved in the formation of spatial rigidity of the intermediate rail fastening nodes under the influence of horizontal transverse forces. Methodology. The study of the track screw and spike rigidity was conducted experimentally for the two types of intermediate rail fastenings – D0 and «Metro». To carry out experimental tests, 10 test sites were selected on the roads of the regional branch of «Southern Railway» of «Ukrzaliznytsia», and 8 – in the main routes of KP «Kharkiv Metro». Each of the test sites was in approximately the same operating conditions, but had different values of passed tonnage. Findings. The values of the track screw and spike rigidity were obtained. Originality. The authors first obtained the experimental data on variation in rigidity of track screw and spike, depending on the useful life for the main railways and subway routes. This allows calculation of the horizontal shear forces in track curved sections (particularly in curves of up to 350 m radius), as well as the forecast evaluation of their level change during operation. Practical value. Based on the experimental data, it was found that variation in rigidity of track screw and spike depending on the lifetime is nonlinear. These experiments allow a more rational approach to the issue of determining the optimal design of the intermediate rail fasteners, based on the specific operating conditions, and may also contribute to the development of measures to improve the reliability of the components of intermediate rail fastenings for wooden sleepers.

115-123

Authors: V. V. Netrebko, I. P. Volchok

Purpose. This paper focuses on obtaining the dependencies of the manganese content in the metallic base (Mno) and its interphase distribution coefficient (KPMn) on the cast iron’s chemical composition in the system Fe–C–Cr – Ni –Mn. Methodology. The cast irons containing 1.09…3.91% С, 0.6…5.4 % Mn, 11.43…25.57 % Crand 0.19…3.01 % Ni have been studied. The active experiment design techniques were applied to build a mathematical model of manganese distribution. Cast iron was smelted in the induction furnace with the capacity of 60 kg, with basic lining.Findings.Manganese, being a carbide-forming element, distributed between carbides and the metallic base. With the use of the mathematical statistics methods, regression dependencies of the manganese concentration in the base and its interphase distribution coefficient on the С, Mn, Cr and Ni content in the cast iron were established. The manganese concentration in the base varied from 0.37 % at 1.09 % С, 0.6 % Mn, 11.43 % Cr and 3.01 % Ni to 5.79 % at1.09% С, 5.4 % Mn, 25.57 % Cr and 0.19 % Ni. The minimum value of the interphase distribution coefficient was 0.16 in the cast iron containing 1.09 % С, 0.6 % Mn, 25.57 % Cr and 3.01 % Ni. When the КРMn coefficient values were lower than 1, manganese concentrated predominantly in the metallic base. The maximum value of the КРMn coefficient was 2.48 at 3.91 % С, 0.6 % Mn, 11.43 % Cr and 0.19 % Ni. The manganese distribution pattern was determined by the carbides’ quantity and chromium and carbon ratio that determined the carbide type. The carbides’ composition was formed as a result of carbide-forming elements contention. Originality. Regression dependencies of the manganese content in the base and its interphase distribution coefficient on the cast iron’s chemical composition in the system Fe–C–Cr – Ni –Mn have been obtained. The dependency of the manganese distribution on the carbide forming processes has been established. Practical value. The obtained dependencies allow predicting the manganese content in the metallic base and may be used during the elaboration of the new wear resistant cast irons compositions.

136-157

Authors: V. M. Bohomaz, M. V. Borenko, S. V. Patsanovskyi, O. O. Tkachov

Purpose.One of the main elements of the inclined belt bucket elevators is their drive. To determine the drive power, it is necessary to carry out calculations according to standard methods, which are described in the modern literature. The basic design parameters are the productivity, lifting height, type and properties of the transported material, the angle of inclination. It is necessary to build a parametric dependence of the driving power of the elevator on its design parameters, which takes into account the standard sizes and types of buckets and belts. Methodology. Using the methodology of traction calculation of inclined belt bucket elevator there were built parametric dependences of efforts in specific points of the route of the elevator, as well as the parametric dependences of the drive power of high-speed elevators with deep and shallow buckets on their design parameters and characteristics. Findings. On the basis of constructed parametric dependencies, it was found that the function of changing the value of the elevator’s power from design capacity (at fixed lifting height, type of cargo, belt speed) is piecewise constant and monotonically increasing. It was built a graphical representation of elevator drive power on the angle of its inclination within acceptable limits of change. The resulting relationship is non-linear and monotonically decreasing. In general terms the intervals of project performance values, which provide a constant value of drive power of inclined elevator were defined. As an example of the obtained results it was observed the process of dependence construction of the drive power on design capacity and inclination angle of the elevator for transporting the fine coal. Originality. For the first time there were constructed the parametric dependences of drive power of inclined bucket elevator on its design parameters that take into account the standard sizes and types of buckets and belts. Practical value. Using the constructed dependencies enables relatively quick determination of the approximate value of the drive power of high-speed inclined elevators with deep and shallow buckets at the design stage and high-quality selection of its basic elements in the design of specific characteristics: type of cargo, productivity, lifting height, angle of inclination.

166-174

Authors: D. V. Rudenko

Purpose. The article focuses on investigation of the stress state of a modified in-situ concrete of natural hardening. Methodology. To achieve the aim, the research of the microstructure of the modified cement matrix of concrete, as well as the mechanism of structure formation of modified concrete with natural hardening was conducted; the methods for reliable evaluation of concrete strength were defined. Findings. The development of internal stresses affects the properties of concretedifferently. With an increase in temperature-shrinkage deformations in time and, thus, with increasing structural stresses in the cement sheath around the grains of the filler two opposite processes may develop: zone of plastic flow or cracking. Originality. It was established that the structural features complex of the modified concrete when the load transfer leads to the formation of extensive zones of prefracture which is able to absorb a significant amount of elastic strain energy that provides the design deformation properties of the concrete for special purposes. Ideas about the definition of the criteria of cracking modified concrete, hardening under natural conditions had further development. Practical value. The resulting equations allow to solve the problem about the minimum level of structural stress in monolithic concrete in a saturated large placeholder, as well as to assess the influence of structural stresses on the properties of concrete. In normal concrete with a relatively thin cement sheath at temperature-shrinkage deformations, high tangential and low radial tension occur. In vivo, this stress is higher as a result of higher values of Δε(τ), which is not observed in the modified concrete. In the modified concretes only tangential stresses are the greatest danger to structures. The change of shrinkage stress with time is straightforward. The total temperature-shrinkage deformations have a sawtooth graph. For modified concrete the amplitude is 48…53% less. This will allow solving a number of technological challenges in the construction of monolithic buildings.