Science and Transport Progress

Problems of Program Code Refactoring with the Use of Artificial Intelligence

O. A. Syrota, V. M. Horiachkin — Tue, 11 Mar 2025 00:00:00 +0200

Purpose. The modern technological landscape is characterized by the rapid development of software focused on various subject areas and platforms. This leads to the continuous creation of new software products consisting of a huge number of lines of code. The process of developing high-quality software is a multi-stage process that involves a number of factors that affect the final result. The key aspects include the competence of developers, the effectiveness of project management, the availability of necessary resources, and the ability to adapt to changing requirements. Each platform has its own specific features that must be taken into account during development, which further complicates the process of creating universal and effective software solutions. Our research aims to conduct a comprehensive analysis of the potential and promising areas of application of large language models in the context of program code refactoring. The work is aimed at developing and improving methods that will help to increase the efficiency of the refactoring process using these models. Methodology. To solve the above problems, it is proposed to implement a set of methods that can be used both separately and in synergy to optimize the final result. These methods, carefully developed in the context of modern software engineering paradigms, are aimed at increasing the efficiency of the refactoring process while ensuring that the software functionality is preserved. Their implementation involves a systematic approach to analyzing and modifying the code base, taking into account both technical aspects and the potential impact on the overall system architecture. Findings. A comprehensive analysis of existing language models has been conducted and methods for improving the efficiency of large language models in the context of code refactoring have been developed. The key factors that influence the success of the proposed methods, including the amount of training data and the limitations of the model context, are identified. Originality. An approach to improving the efficiency of large language models in code refactoring that takes into account the specifics of different projects and development stages is developed. Innovative methods for retraining language models and optimizing the use of context are proposed, which expand the capabilities of automated refactoring. Practical value. The results of the study allow to improve the efficiency of code refactoring using large language models.

Modeling the Performance of a Towel Dryer in a Low-Temperature Microclimate System

N. D. Stepanova, D. M. Snisarchuk — Thu, 06 Mar 2025 00:00:00 +0200

Purpose. The article is aimed at: investigating the operating conditions of a water-type towel dryer made of polished stainless steel AISI 304 in a low-temperature microclimate system; conducting a comparative analysis of the declared thermal power of towel dryers of the same design from different manufacturers, which will reveal significant differences between theoretical and real indicators; considering methods for determining the rated thermal power of a towel dryer, taking into account the forced movement of the coolant in the middle of the device pipeline, and so on. Methodology. The influence of various boundary conditions on compliance with the requirements of current regulatory documents for assessing the thermal efficiency of heating devices is analyzed. Numerical modeling of thermal processes in the SolidWorks Flow Simulation environment was used to study the operation of a towel dryer. The influence of the uncertainty of the blackness coefficient of the towel dryer surface on its thermal efficiency, as well as the role of the speed of air flow around the heat exchange surface, was evaluated. It was found that a decrease in the coolant temperature significantly affects the performance of the towel dryer: a decrease in the coolant temperature from 75 to 45 °C leads to a loss of 60–64 % of the heat output, and a decrease to 30 °C leads to a decrease in the output by 85.5–87.9 %. Findings. The results of modeling the thermal power of a towel dryer were compared with experimental data obtained in a certified laboratory. It was found that the results obtained by the first method correlate with laboratory tests to within 1 %, while the second method has an error of 5.6 %. The discrepancy between the results of modeling in SolidWorks Flow Simulation and laboratory tests is 20.23 %, which is due to the peculiarities of the computational models. Originality. The optimal design characteristics of heated towel rails for use in low-temperature systems have been determined, and recommendations for increasing the heat exchange surface of heated towel rails by optimizing the number and length of horizontal elements have been proposed. Practical value. Improving the reliability of calculations of the thermal capacity of towel dryers will help to improve their energy efficiency in modern heat supply systems. The results obtained can be useful for manufacturers of heating devices, heating engineers, as well as specialists involved in the design and modernization of heat supply systems for residential and public buildings.

Estimation of the Forecasted Cargo Flow of an Inter-/multimodal Transport and Logistics Center

V. K. Myronenko, Y. O. Ziubryk — Wed, 19 Mar 2025 00:00:00 +0200

Purpose. The study is aimed at obtaining new knowledge about the patterns of formation of cargo flows generated (induced) during the creation of transport and logistics centers serving multi / intermodal cargo transportation, using products and services of scientometric databases. The timeframe of the studied sources is 2010–2024. Methodology. To obtain relevant empirical data, the authors reviewed the literature and official websites of transport and logistics centers (TLCs) in the EU countries, which reflect data on their infrastructure and workloads in servicing various modes of transport. Findings. In the course of the work it was found that: 1) the studied set of TLCs of the EU countries can be clustered by the ratio «TLC area, ha – generated annual cargo flow per unit area of TLC, t/(m²-yr)»; 2) clusters of large, small and medium-sized (by area) TLCs can be conditionally distinguished; 3) as a rule, small TLCs generate more cargo per unit area, which sets the goal for further research – to determine the optimal area and other parameters of TLCs according to the criterion of its maximum specific productivity per unit area. Scientific originality. For the first time, the authors obtained quantitative dependencies of the ratio of «TLC area, ha – generated annual cargo flow per unit area of TLC, t/(m²-yr)», which have the character of a decreasing power function for small and medium-sized TLCs and a decreasing linear function for large (by area) TLCs. Practical value. Based on the results obtained, it is possible to predict the size of the generated cargo flow depending on the selected design solutions when creating new TLCs, which will increase the reliability of feasibility studies for relevant investment projects. These studies can also be useful in the educational process in the areas of «Railway Transport», «Transport Technologies», «Construction and Design of Transport Infrastructure», in the study of the disciplines «Multimodal Freight Transportation», «Logistics of International Freight Transportation», organization of scientific and practical seminars, advanced training courses, etc.

Recycling Lead Acid Car Batteries: Challenges and Prospects

V. E. Olishevska, H. P. Ivanova, H. S. Olishevskyi — Mon, 24 Mar 2025 00:00:00 +0200

Purpose. Road transport plays an important role in the functioning and development of the country's economy, but its operation is accompanied by a negative impact on the environment, consumption of scarce resources and an increase in the amount of waste, among which the most dangerous are spent lead-acid batteries. The main purpose of the study is to investigate the current state of recycling of lead-acid car batteries in the context of the economic crisis, energy shortages and intense environmental pollution, as well as to determine its prospects in Ukraine. Methodology. Today, there is a rapid increase in the level of motorization in our country, which causes a significant increase in the number of lead-acid batteries that need to be recycled. The lack of modern, efficient infrastructure for collecting used car batteries often leads to their ending up in landfills. This negative trend causes the loss of valuable secondary materials and environmental pollution. Current technologies for recycling lead-acid batteries are characterized by insufficient efficiency and require significant financial costs. An important challenge is the negative impact of battery recycling technology on the environment. Promising areas that will allow the recycling of lead-acid batteries include the creation of a modern infrastructure for battery collection and recycling and the development of recycling technologies, including the use of lead from batteries in the production of radiation-resistant concrete. A comprehensive study of the problem of recycling lead-acid batteries will satisfy the need to save resources and increase the rational use of resources contained in spent lead-acid batteries. Findings. The current state and problems of recycling lead-acid batteries for cars are analyzed. It is shown that battery scrap recycling allows solving two urgent problems: environmental protection and obtaining valuable secondary raw materials. The possibilities of using a vibrating jaw crusher with an inclined crushing chamber for the processing of battery scrap were investigated. Originality. A comprehensive analysis of the problem of recycling lead-acid car batteries was carried out, which allowed to identify specific features, development trends and challenges. The possibility of using a vibrating jaw crusher with an inclined crushing chamber for the processing of battery scrap is substantiated. Practical value. The main directions and problems of recycling lead-acid car batteries, the use of recycling products, including in the construction industry, are considered. It is proposed to use a vibrating jaw crusher with an inclined crushing chamber for the processing of lead-acid batteries.

Influence of Materials and Scale Factor on Failure of K-shaped Nodes of Pipe Concrete Bridges: Effectiveness of Design Parameters

D. S. Spivak, S. V. Kliuchnyk — Mon, 10 Mar 2025 00:00:00 +0200

Purpose. The paper aims to analyze the stress-strain state of K-shaped nodes of pipe-concrete structures using finite element modeling with consideration of nonlinear characteristics of materials, which, in turn, requires an assessment of the influence of materials and node sizes on the operation of hollow braces in lattice bridge structures. Methodology. Numerical modeling of the stress-strain state of K-shaped nodes of pipe concrete belts in the ANSYS program was performed. Two classes of concrete (C16/20 and C50/60) and two steel grades (16D and 10HSND) were used for the analysis, which were modeled using the Drucker-Prager plasticity criterion for concrete and the multilinear isotropic strengthening tool for steel. We prepared 12 variants of the node models with different material characteristics and two dimensional scales. To approximate the real state, the assemblies were loaded in two stages: first, the belt was loaded, and then the braces were loaded until they failed. Findings. The calculations showed that the deformation of hollow specimens of nodes corresponds to the laboratory experiments of other authors. The effect of concrete filling on compressed and tensile braces was significant, especially for compressed braces, where the effect reached 20.8%. C50/60 concrete does not always improve performance, sometimes being inferior to C16/20 concrete. Increasing the node size has a positive effect on concrete efficiency, particularly for compressed struts, where the increase was up to 12.3%. Increasing the strength of steel from 16D to 10KhSND for tensile braces showed an efficiency of 0 to 8.6%, and for compressed braces - up to 22.8%. Stress plots along the weld showed that concrete helps to distribute stresses evenly in both compressed and tensile braces. Originality. The paper analyzes the influence of materials and geometry of steel assemblies partially filled with concrete on the performance of hollow braces, with special attention paid to the little-studied factor of the assembly size. Practical value. Thanks to the finite element nonlinear analysis and the application of Ukrainian regulations and European standards, the principles of optimal selection of concrete and steel classes for pipe concrete K-shaped assemblies have been established. This makes it possible to ensure the reliability of modern bridge lattice structures, increase their efficiency and cost-effectiveness.

Study of the Influence of Graphene Contacts on the Efficiency of Photovoltaic Conversion in a Multi-junction Solar Cell with Vertical p–n Junctions

A. B. Gnilenko, S. V. Plaksin — Mon, 24 Mar 2025 00:00:00 +0200

Purpose. The research is aimed at improving the design of a multi-junction solar cell with vertically arranged p–n junctions. The purpose of the study is to increase the efficiency of photovoltaic conversion under oblique incidence of sunlight. Methodology. To achieve the goal of the research, it is proposed to use transparent graphene layers as contacts between the series-connected elementary p–i–n cells of a multi-junction solar cell instead of metallizing the side surfaces of the cells with aluminum. A model of the studied solar cell was built using the Silvaco TCAD software package, and a series of computer experiments were conducted to obtain the main electrical characteristics and analyze their dependence on the parameters of the solar cell. The mathematical model used in Silvaco TCAD for modeling semiconductor devices involves solving the fundamental Poisson equations, continuity, and transport equations based on the diffusion-drift transport model. Findings. Based on the computer modeling, the authors proved that the use of graphene contacts between the elementary p–i–n cells of a multi-junction solar cell instead of traditional aluminum metallization allows to significantly increase the solar cell efficiency under oblique incidence of sunlight. Thus, replacing metal contacts with graphene ones allows to increase the efficiency coefficient of the solar cell by 15% at an angle of 45° of solar radiation incidence. Originality. The authors first proposed the design and conducted computer simulation of a multi-junction solar cell with vertically arranged p-n junctions in which the usual metal contacts between the series-connected elementary solar cells are replaced by transparent layers of graphene. Practical value. The simulation results confirm the possibility of using the proposed solar cell design in conditions of oblique incidence of sunlight. Such properties of the solar cell allow its use on vertical, inclined or moving surfaces, including vehicles and transport infrastructure, where it is practically impossible to ensure the optimal angle of incidence of solar radiation.

Mathematical models for water treatment problems

Thu, 13 Mar 2025 00:00:00 +0200

Purpose. Assessing the efficiency of water treatment in different structures is a problem of big importance. To solve this a problem, it is necessary to have mathematical models that allow to quickly obtain data on the cleaning effect in different structures. The aim of the work is to develop numerical models to determine the efficiency of water treatment in an aeration tanks, settlers and mixers. Methodology. For mathematical modeling of the process of water treatment in a bioreactor, balance equations were used. These equations allow to determine concentrations of substrate, activated sludge and dissolved oxygen in s structure. The Monod model is used to calculate the substrate oxidation process. To study effectiveness of water treatment process in vertical settler Euler’s equation were used with convective-diffusive equation. To simulate reagent mixing in mixer equation of potential and convective-diffusive equation were used. To solve governing equations finite- difference schemes of splitting were used. Findings. A tool for theoretical assessment mass transfer processes in aeration tank, vertical settler, mixer was developed. Originality. Effective numerical models to simulate water treatment in bioreactor, vertical settler, mixer were developed. Fundamental equations of Fluid Dynamics and Mass Transfer were used to build the models. Proposed models can be used in practice at the stage of «sketch designing». The models take into account the main physical parameters which influence the process of Mass Transfer and are quick computing. Practical value. The constructed mathematical model can be useful during the reconstruction and designing structures for water treatment. Computer programs have been developed to carry out numerical experiment. The results of a computer experiment are presented.

Express Model for Analyzing the Process of Soil Heating in a Greenhouse

V. V. Biliaieva, S. A. Shcherbyna — Mon, 10 Mar 2025 00:00:00 +0200

Purpose. The organization of artificial soil heating in a greenhouse plays an important role in ensuring efficient plant cultivation, as the optimal soil temperature is a key factor in this process. The heating itself must be carried out in such a way as to ensure a certain temperature range in the soil, in particular in the area where the root system of plants is located. The soil heating process depends on the specific operating conditions of the greenhouse. To organize a rational and energy-saving process, it is necessary to determine the parameters of the heating system in advance, at the design stage. An effective method for solving this problem is to use mathematical models. The main purpose of the study is to develop a one-dimensional express model for evaluating the process of soil heating in a greenhouse. Methodology. The equation of thermal conductivity was used to study the dynamics of artificial soil heating. The numerical integration of the modeling equation was carried out using a finite-difference scheme of total approximation. Findings. A computer program has been developed that can be used to conduct a computational experiment to determine the dynamics of artificial soil heating in a greenhouse. The results of numerical modeling are presented. Originality. A one-dimensional numerical model for analyzing artificial soil heating in a greenhouse has been developed. The model is based on the numerical integration of the heat conduction equation and allows us to quickly determine the dynamics of the formation of thermal fields in the soil both in the case of the heating element operation and in the case of its shutdown. Practical value. The developed numerical model can be a useful tool at the design stage of artificial soil heating systems. It provides scientific justification for the parameters of heating systems and energy-efficient modes of their operation. The model allows you to quickly assess the dynamics of thermal fields in the soil both during the operation of the heating element and after it is turned off. For practical application of the numerical model, only standard input information is required. Controlling the dynamics of soil heating opens up opportunities for optimal control of the heating system operation modes.

Mathematical Modeling of Thermal Regime in the Launch Vehicle Fairing at the Stage of Prelaunch Preparation

Fri, 21 Mar 2025 00:00:00 +0200

Purpose. The development of satellite communication systems is based on the transportation of satellites in space. The satellite is transported into orbit by a launch vehicle. The satellite is placed in the transportation compartment in the middle of the main fairing. At the pre-launch stage, it is necessary to comply with the harsh environmental conditions inside the main fairing. In particular, it is very important to predict the temperature field in the transport compartment inside the main fairing during its forced ventilation at the pre-launch stage. To solve this problem, it is necessary to have specialized mathematical models. The main goal of this work is to develop a fast-calculating model for estimating the temperature fields inside the launch vehicle fairing. Methodology. The energy equation was used to calculate the temperature field formed by the ventilation of the transport compartment and the heat generated by various elements of the satellite. This equation took into account the intensity of heat emission from different parts of the satellite, the pattern of airflow around the satellite, and heat transfer in the transportation compartment. The inhomogeneous airflow velocity field in the cargo compartment was calculated based on a potential flow model. Finite-difference schemes are used for numerical integration of the model equations. Findings. A computer code has been developed that implements the proposed numerical model. The results of computational experiments to assess the temperature regime in the main fairing of the launch vehicle for different satellites are presented. Originality. A fast-calculating CFD model for analyzing thermal fields in the middle of the launch vehicle fairing at the stage of prelaunch preparation has been created. The model makes it possible to determine the zones with sub- and over-temperature in the middle of the fairing. Practical value. The developed numerical model can be useful for selecting and justifying the ventilation mode of the main fairing of the launch vehicle at the pre-launch stage in order to ensure the recommended temperature range near the satellite. It can also be used for the initial assessment of the temperature in the main fairing at the stage of justifying the thermal control mode for a particular satellite or satellite system.

Mathematical Modeling of Air Pollution Near Roads and Assessment of Disease Risk in People Exposed to Vehicle Emissions

Tue, 18 Mar 2025 00:00:00 +0200

Purpose. The work is aimed at developing a numerical 2D model that allows for the rapid calculation of the absorption of polluted air near the road. A fast CFD model should take into account meteorological parameters, a suction pipe near the road to remove polluted air, and the rate of toxic gas emissions. Methodology. The developed model is based on the potential flow equation and the pollutant mass transfer equation. The potential flux equation is used to calculate the wind flow near the road in the case of a suction pipe. The Liebman numerical integration method was used to solve the potential flow equation. To solve the convective-diffusive dispersion equation, an implicit variable-triangular difference scheme was used. The numerical integration is carried out using a rectangular difference grid. The porosity method (“marker method”) was used to create the shape of the complex computational zone. Toxic gas emissions from a car were modeled using the Dirac delta function for a point source. Findings. The developed numerical 2D model takes into account the main physical factors that affect the process of dispersion of pollutants near the road. The model takes into account the influence of a car and a suction pipe located near the road to remove polluted air. On the basis of the developed numerical models, a computational experiment was conducted to assess the impact of the use of a suction pipe on local air pollution near the road. Originality. The developed numerical model allows to calculate a two-dimensional flow pattern near the road, where such a mitigation measure as a suction pipe is used. The model allows for quick calculations of air pollution, taking into account the impact of the protective barrier. Based on the data on the distribution of the concentration of a non-hazardous substance, the risk of disease in a person exposed to vehicle emissions was determined. Practical value. The software implementation of the developed numerical model was carried out, and a computational experiment was conducted to illustrate the effectiveness of using the model to solve applied problems. The results of the numerical experiment are presented.

Fast Computational Models in Water Use Problems

Wed, 05 Mar 2025 00:00:00 +0200

Purpose. At the stage of preliminary design of various structures in water supply and wastewater systems, it is necessary to have a set of mathematical models to perform serial calculations to assess the efficiency of these structures in different conditions. Mathematical models are needed that take into account the basic physical factors. Such models are mathematical models of hydrodynamics and mass transfer. The complexity of the mathematical formulation of mass transfer problems for water supply and wastewater treatment systems lies in the use of numerical methods. This is due to the fact that multifactor differential equations are used in fundamental models of continuum mechanics. For practical use, it is especially important to have fast numerical models to perform serial calculations during a working day. The main purpose of this work is to develop fast-calculating numerical models for solving a set of problems in the field of water supply and sewerage. Methodology. The fundamental equations of continuum mechanics are used to solve mass transfer problems: the equation for the velocity potential, the filtration equation, and the equation for convective-diffusive impurity transfer. Finite difference schemes are used for numerical integration of the modeling equations. The construction of finite-difference schemes is carried out in such a way as to obtain equations for which explicit formulas can be used to solve. The numerical integration of the modeling equations is carried out on a rectangular difference grid. Findings. A set of numerical models has been developed that can be used at the stage of preliminary design of water supply and wastewater treatment facilities. The constructed numerical models take into account the main physical factors that affect the processes of mass transfer in these structures. Originality. A set of mathematical models is proposed to study multifactorial mass transfer processes in water supply and sewage facilities. Numerical models take into account the convective diffusion process of impurity propagation. Practical value. The constructed numerical models can be used in the design of pressure filters, water intakes, and wastewater neutralization facilities.

Evaluation of gabions usage effectiveness for industrial facilities protection against damage

Mon, 24 Mar 2025 00:00:00 +0200

Purpose. In the extreme situations at industrial sites, various damaging factors may appear, such as the spread of toxic substances in the air, the creation of a fireball, etc., which pose a threat to the lives of workers and have a significant negative impact on the environment. That is why today, special attention is being paid to the problems associated with the spread of debris during a drone attack. At an industrial site where oil product storage facilities are located, the debris generated during an explosion can damage the tank building and cause a fire. In this regard, the main objective of the study is to evaluate the effectiveness of using gabion to reduce the risk of damage to the oil storage facility during the movement of drone debris. Methodology. To achieve this goal, the paper considers the problem of flying debris in the event of a drone explosion at an industrial site where oil storage facilities are located. The use of gabion with sand is proposed to protect the tank building from the throwing effect of debris. It is proposed to develop a mathematical model of the movement of a fragment in the path of which the gabion is located. The effect of gabion as a protective screen on reducing the air temperature near a neighboring oil storage facility in the event of a fire at an industrial site is also considered. A model of the dynamics of a point motion (Newton's second law) was used to mathematically describe the movement of the debris. Numerical integration of the modeling equations was performed using the Euler's method. The energy equation was used to model the process of thermal air pollution at an industrial site during a fire. Findings. In this work, the numerical model was programmed and a computer code was created. The programming language is FORTRAN. The code provides information on the speed of the fragment movement in different parts of each zone. On the basis of the constructed numerical model and the created code, parametric studies were carried out to determine the effectiveness of using gabion with sand to protect the oil storage facility from the effects of fragment. As an approximation, the case when the fragment after the explosion moves horizontally in the direction of the object was considered. The influence of the gabion height on the heating level of the wall of the oil storage facility located at an industrial site was analyzed. Originality. An effective mathematical model has been developed to evaluate the effectiveness of using gabion to protect the oil storage facility from damage by drone fragment. The proposed model allows determining the rational dimensions of the gabion to reduce the risk of damage to the tank wall. An effective computer model of thermal air pollution at an industrial site in the event of a fire at an oil storage facility is presented. Practical value. On the basis of the constructed mathematical model, a computer code was created to conduct a computational experiment to determine the effectiveness of using protective barriers (gabions) on the territory of an industrial site.

Prospects for the Implementation of High-Speed Railway in Ukraine

M. B. Kurhan, D. M. Kurhan, N. P. Khmelevska, D. L. Kovalskyi — Wed, 12 Mar 2025 00:00:00 +0200

Purpose. The European Union has an ambitious goal of significantly expanding the network of high-speed railway lines. Currently, Ukraine lacks direct experience in constructing high-speed railways compared to European projects. Despite this, Ukraine has a strategy for developing high-speed rail connections. This study aims to analyze and justify the conditions under which the construction of the Kyiv–Lviv–Warsaw high-speed rail corridor can become an economically viable project, bringing significant economic, social, and environmental benefits. Methodology. To assess the feasibility of constructing a high-speed railway along a new route, the authors applied a forecasting and efficiency evaluation model for railway transportation, considering all costs using the NPV (Net Present Value of Discounted Cash Flow) indicator. NPV serves as a powerful tool for investment project evaluation, allowing for informed financial decision-making by considering the time value of money and maximizing investment profitability. Findings. The study identifies the conditions under which the construction of the Kyiv–Lviv–Warsaw high-speed rail corridor can become an economically viable project. As passenger train volumes increase, the net discounted revenue grows linearly, with its magnitude depending on the construction costs of the high-speed railway. To enhance project profitability, it is more critical to focus on increasing transportation volumes rather than reducing construction costs. Originality. The new findings are based on the application of scientific approaches such as a comprehensive and detailed study of various aspects of high-speed railway design in Europe. This has enabled the improvement of the interoperability between Ukrainian and European transport systems and provided recommendations for organizing high-speed rail services in Ukraine. Practical value. Based on the obtained results, further development of railway infrastructure along high-speed rail corridors is possible through innovative advancements and the enhancement of scientific and technological potential. Addressing issues related to the implementation of analysis and evaluation methods for selecting high-speed rail options serves as the foundation for the planning and construction of high-speed railway routes in Ukraine.

Hybrid Traction System for a Haulage Locomotive for Industrial Quarry Railways

Ie. S. Riabov, B. Kh. Yeritsian, A. S. Tykhonov, O. A. Khazov — Wed, 19 Mar 2025 00:00:00 +0200

Purpose. The article aims to determine the parameters of a hybrid traction system for a diesel locomotive for haulage work on industrial quarry railways. Methodology. The study was carried out on the example of a section of the quarry railroad of the Northern Mining and Processing Plant. It is shown that in order to determine the parameters of the traction system, it is necessary to take into account the work in the traction and braking systems for the freight and empty semi-trains. The calculations were performed using the provisions of the theory of locomotive traction. Findings. It has been determined that on a given track profile with a maximum elevation of 35 ‰, a two-section twelve-axle diesel locomotive can drive a train with 12 loaded cars (dump cars). The speed is 10 km/h, and the power output is about 2,400 kW. To ensure the braking of a loaded train on the studied route (the largest slope (downhill) is 28 ‰), the tangential power should be 3,000 kW, and the movement will be carried out at a speed of 15 km/h. It is proposed to use a hybrid traction system, the power plant of which includes an energy storage device. To ensure high traction properties, it is necessary to use a traction electric drive based on AC motors. When using traction asynchronous electric motors, it is possible to use bogie power supply and control of electric motors, which will ensure high traction properties of the locomotive. The expediency of equipping the locomotive with devices that provide its power supply from the contact network while moving along electrified sections is shown. A 3D sketch of the hybrid traction system equipment placement on the 2TE10M diesel locomotive was developed. To develop the sketch, models of an 800 kW diesel generator set and a 500 kWh energy storage device with a peak capacity of 1,000 kW were used. Originality. The parameters of a dual-mode locomotive equipped with a hybrid traction system and designed for haulage operations on industrial quarry railways have been determined. Practical value. The obtained results can be used in the development of projects for the modernization of diesel locomotives and the creation of new traction rolling stock for quarry and mainline railways.

Study of the Longitudinal Dynamics of Passenger Trains to Provide Recommendations for Their Control on New Sections of the Azerbaijan Railways

L. V. Ursulyak, O. O. Bolotov — Mon, 24 Mar 2025 00:00:00 +0200

Purpose. In order to organize safe, longitudinal dynamics, train traffic on the sections of the Azerbaijan Railways that are being put into operation, the paper provides recommendations for controlling the movement of passenger trains and electric trains to realize the maximum possible speed, taking into account the technical capabilities of locomotives and the parameters of the longitudinal profile. Methodology. The estimation of the largest values of longitudinal accelerations was performed by means of computer modeling of longitudinal oscillations of passenger trains while they are moving at different speeds in areas with the most unfavorable parameters of the profile and track plan, which are superimposed on the train disturbances caused by the driver's actions to control its movement. The paper presents mathematical modeling of the force characteristics of inter-car connections of passenger cars equipped with modernized rubber-metal absorbing devices. To confirm the validity of the mathematical model, the maximum values of longitudinal accelerations of cars and braking distances obtained as a result of mathematical modeling of passenger trains were compared with similar values obtained during experimental trips. Findings. Using computer modeling of longitudinal train oscillations, diagrams of the distribution of the largest longitudinal accelerations along the length of trains with different numbers of cars, the magnitude of braking distances, and braking times were obtained. For the proposed modes of train control, the dependence of the speed on the track coordinate is analyzed. It is noted that for the considered modes of operation of passenger trains and electric trains with the specified speeds on certain sections of railways, the level of longitudinal accelerations of cars does not exceed the values that will affect the safety of train traffic and the comfort of passenger travel. Originality. For the first time, the authors proposed a mathematical model of the power characteristic of the modernized absorber apparatus, which is used in passenger cars on the Azerbaijan Railways. The longitudinal load of electric trains and passenger trains, as well as speed curves in different modes of train operation on certain sections of the Azerbaijan Railways were investigated. Practical value. Based on the results obtained, recommendations for controlling the movement of passenger trains on real track sections to maintain a given speed, taking into account the technical capabilities of locomotives and longitudinal profile parameters, were provided.

Research of the Influence of Design Parameters of a Scraper Conveyor with an Upper Working Branch on its Technical Characteristics

V. M. Bogomaz, V. J. Nagachevskyi — Tue, 11 Mar 2025 00:00:00 +0200

Purpose. The research is aimed at: determining the nature of the influence of design parameters on the technical characteristics of a scraper conveyor with an upper working branch (width, height of the chute and drive power); building analytical dependencies of these values on the design characteristics: type and physical and mechanical properties of the cargo, transportation length, productivity, angle of inclination of the route; conducting a graphical analysis of the nature of the influence. Methodology. To achieve this goal, we used the calculation algorithms presented in the modern technical literature, analyzed the factors and values that affect the value of the drive power and the geometric parameters of the conveyor chute. It has been established that to determine the drive power of vibratory conveyors, it is necessary to carry out a detailed calculation, which includes: the width and height of the chute, the pitch and height of the scrapers, the forces at the characteristic points of the route by the method of traversing the contour, and the resistance to load movement. Findings. For a scraper conveyor with an upper working branch designed to transport unsorted coal, a graphical analysis of the influence of the transportation length, the angle of inclination of the route, and productivity on the drive power and geometric dimensions of the chute was carried out. It was found that the function of change in the width of the conveyor chute on the capacity is increasing (with other parameters fixed), and on the angle of inclination - a stepwise increasing function; the function of change in the drive power on the capacity and length of transportation - linearly increasing, on the angle of inclination of the route - nonlinearly increasing. Originality. The author first studied the dependence of drive power and chute width of a scraper conveyor with an upper working branch, built analytical dependencies of technical characteristics (drive power, chute width and height) on design parameters: productivity, transportation length, type and physical and mechanical properties of the transported cargo, and the angle of inclination of the route. For a conveyor that transports unsorted coal, graphical dependencies of the chute width and drive power on the capacity, transportation length, and route angle were constructed. Practical value. The use of the constructed dependencies makes it possible to determine the general nature of the change in the above technical characteristics in the case of varying design parameters such as capacity, conveyor length, and angle of inclination. The proposed dependencies can be used to quickly determine the rational power of the conveyor drive for specific design data.