Статті КЕСЕ (ДМетІ)

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Analysis of Air Dust Pollution in the Transport Compartment of the Launch Vehicle at the Stage of the Pre-launch Preparation
(Printing House “Technologija”, Kaunas, Lithuania, 2024) Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Kozachyna, Vitalii A.; Kozachyna, Valeriia V.; Mashykhina, Polina B.; Semenenko, Pavlo
ENG: At the stage of the pre-launch preparation, it is necessary to fulfill very strict environment conditions inside the main fairing where the satellite is located. Namely, it is very important to predict dust concentration inside the main fairing and especially near satellite surface during forced ventilation. To predict air dust pollution inside of main fairing 2D fluid dynamics numerical model has been developed. The governing equations include equation of potential flow to simulate air flow inside the main fairing and equation of pollutant dispersion. Also, empirical model has been used to calculate the number of dust particles fall to the satellite surface. Implicit finite difference schemes of splitting have been used for numerical integration of governing equations. The computer code has been developed on the basis of proposed numerical model. The results of computational experiments to estimate dust concentration field inside the main fairing of the launch vehicle are presented.
Analysis of Changes in Global Warming Potential during Enrichment and Production of Battery-Grade Graphite Using Electrothermal Fluidized Bed Technology
(IOP Publishing Ltd, 2024) Hubynskyi, Semen M.; Sybir, Artem; Fedorov, Serhii S.; Usenko, Andrii Yu.; Hubynskyi, Mykhailo V.; Vvedenska, Tetyana
ENG: The greenhouse gas emissions during the production of anode class graphite for the conditions of Ukraine have been calculated. Conventional technologies and technologies using electrothermal fluidized bed (EFB) for natural and synthetic graphite have been studied. Calculations are carried out with respect to the whole technological chain, starting from extraction and processing of raw materials and ending with finishing processing (coating). As a result, it is shown that the technology of using EFB for purification of natural graphite and graphitization of synthetic graphite is competitive in terms of global warming potential (GWP). In the production of natural graphite using thermal purification with EFB instead of chemical purification, emissions of greenhouse gases practically remain at the same level. At the same time, the use of acids is eliminated, and the environmental impact associated with them is reduced. Production of synthetic graphite of anodic quality in EFB furnaces allows to reduce greenhouse gases (GHG) emissions by 40-50% in comparison with traditional graphitization technologies in Acheson and Kastner furnaces. The effect is achieved by reducing energy and raw material consumption.
Application of Biomass Pellets for Iron Ore Sintering
(Trans Tech Publications Ltd, Switzerland, 2021) Kieush, Lina; Koveria, Andrii; Qiao Zhu, Zuo; Boyko, Maksym M.; Sova, Artem; Yefimenko, Vadym
ENG: Purpose. The use of biomass as fuel might solve several technological and environmental issues and overcome certain challenges of sinter production. In particular, as revealed by comprehensive analyses, biomass can be used as fuel for iron ore sintering. In this study, we investigate the use of some raw and pyrolysis-processed biomass pellet types, namely wood, sunflower husks (SFH), and straw, for iron ore sintering. In the experiments, the pyrolysis temperature was set to 673, 873, 1073, and 1273 K, and the proportion of biomass in the fuel composition was set to 25%. It was established that the addition of biofuels to the sintering blend leads to an increase in the gas permeability of the sintered layer. The analysis of the complex characteristics of the sintering process and the sinter strength showed the high potential of wood and sunflower husk pellets pyrolyzed at 1073 and 873 K, respectively, for iron ore sintering. The analysis of the macrostructure of the sinter samples obtained using biomaterials revealed that with higher pyrolysis temperatures; the materials tend to have greater sizes and higher amounts of pores and cracks. The composition analyses of the resultant sinters revealed that with higher temperature, the FeO content of the sinters tends to increase.
CFD Modeling of Traffic-related Air Pollution in Street Canyon
(Printing House “Technologija”, Kaunas, Lithuania, 2024) Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Berlov, Oleksandr V.; Kozachyna, Vitalii A.; Kozachyna, Valeriia V.; Yakubovska, Zinaida M.
ENG: High pollution levels are often observed in urban street canyons. Different mathematical models are intensively used to predict pollution levels in urban street canyons. In this paper quick computing 3D CFD model is proposed to compute wind flow over buildings and pollutant dispersion in street canyon. To simulate wind flow over buildings 3D equation of potential flow has been used. Pollutant concentration field has been modelled using three-dimensional equation of pollutant dispersion. Governing equations are also included simplified equations to describe pollutants chemical transformations in atmosphere. To solve numerically governing equations implicit difference schemes have been used. The computer code to realize the proposed numerical models has been developed. Results of numerical experiments are presented.
Construction of a Mathematical Model of the Heat and Mass Transfer Process in the Main Fairing of a Launch Vehicle at the Pre-Launch Preparation Stage
(TECHNOLOGY CENTER PC, Kharkiv, 2025) Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Rusakova, Tetiana I.; Kozachyna, Vitalii A.; Semenenko, Pavlo V.; Berlov, Oleksandr V.; Kirichenko, Pavlo S.; Hrudkina, Nataliia S.; Voitenko, Yuliia V.; Dolzhenkova, Olena V.
ENG: This study investigates the sequential and continuous formation of thermal fields in the main fairing of a launch vehicle when using protective screens. While thermostating, it is necessary to predict the risk in overheating the payload body and, if necessary, take measures to reduce the temperature near the payload. An engineering solution to this problem can be found through the use of protective screens of various configurations inside the main fairing. These screens reduce the heat flow from the heated outer wall of the fairing to the payload surface. However, there are no standard methods for solving this problem. To evaluate the effectiveness of this protection, a numerical model based on the fundamental equations of continuum mechanics has been constructed. The modeling equations include the energy equation and the equation of motion of a non-viscous gas. Using the numerical model built, a computational experiment was conducted, which confirmed the effectiveness of using protective screens to shield the payload body from excessive heating. The computer time required to perform the computational experiment is 3 seconds. This makes it possible to perform a significant number of calculations in a working day. The proposed simple technical means for protecting the payload from excessive heating could be used in the design of new models for rocket technology. Applying these screens slightly reduces the need for large volumes of clean air. The numerical model built could be used at specialized organizations at the “for-sketch” design stage. Numerical experiments have shown that the use of protective screens inside the main fairing makes it possible to achieve a temperature 2–4°C lower than the maximum permissible temperature near the payload.
Development of a New Ergonomic Risks Management Algorithm on the Example of Drivers
(РС ТЕСHNOLOGY СЕNTЕR, Kharkiv, 2024) Tsopa, Vitaliy; Cheberiachko, Serhii; Cheberiachko, Yurii; Deryugin, Oleg; Chencheva, Olga; Rieznik, Dmytro; Klimov, Eduard; Lashko, Yevhenii; Pashko, Dmytro; Biliaieva, Viktoriia V.
ENG: The object of the study: the process of determining and managing ergonomic risks at workplaces when performing professional activities on the example of truck drivers. The problem lies in uncertainty when making decisions in occupational safety and health management systems. The hypothesis of the study was the possibility of assessing ergonomic risks in the occupational safety management systems of organizations based on the identification of regularities between the load index, typical working postures when performing operations and the intensity of joint movements. An ergonomic risk assessment algorithm was developed, taking into account the load index, which includes a sequence of eleven steps, which can be conditionally divided into three groups. The first is determination of the intensity of joint movement. The second is the determination of the impact of activity and the duration of the production task. The third is determining the impact of environmental factors. An assessment of the ergonomic risk of drivers was carried out for three types of production work: driving a vehicle, replacing a damaged wheel, and repairing a car. At the same time, the ergonomic risk assessment algorithm takes into account the worker’s individual state of health and environmental factors, as well as experience and work experience. It has been established that there is a high level of ergonomic risk during car maintenance due to the highest total load index, which is 30 % higher compared to other types of work of vehicle drivers. The practical application consists in the development of a universal check list of drivers based on an algorithm to determine the ergonomic risk of workers at workplaces, which consists of 11 steps.
Effect of Parameters of the Anthracite Heat Treatment on the Properties of Carbon Materials during Shock Heating
(Ukrainian State University of Chemical Technology, Dnipro, Ukraine, 2022) Sybir, A. V.; Hubynskyi, M. V.; Balalaiev, K. B.; Burchak, O. V.; Sukhyy, K. M.; Fedorov, Serhii S.; Pinchuk, Valeriia O.; Hubynskyi, Semen M.; Vvedenska, T. Y.
ENG: The aim of the study was to experimentally determine the effect of the heat treatment parameters of anthracites from Donetsk basin on the properties of carbon materials when using shock heating, typical of furnaces with a fluidized electrothermal bed. Anthracite was treated in an electric thermal furnace at the heating rate of 1000 K/min and the holding time of 10–20 min. The processing temperature range was 1500–30000Ñ. For processing, we used initial anthracites and anthracites after calcination at 1100–12000Ñ. The properties of the carbon material were investigated by X-ray radiographic analysis, XRF analysis and diffuse reflectance infrared Fourier transform. It was found that precalcination did not produce any effect on the properties of anthracite carbon materials during shock heating and holding time less than 1 hour. Based on the results of studies of anthracite heat treatment while changing the holding time, the following kinetic characteristics of transformations during shock heating were determined: the pre-exponential coefficient of 1.79 and the apparent activation energy of 103.85 kJ/mol. Thermal processing of anthracite from Donetsk coal basin in electric furnaces with the fluidized bed at the temperature 30000Ñ for 55–60 min allows obtaining the crystalline structure characteristic of artificial graphite with necessary electroconductivity and element composition.
Effect of Vapor Treatment on the Caking Properties of Different Coal Types
(MDPI AG, Basel, Switzerland, 2026) Koveria, Andrii; Saik, Pavlo; Polyanska, Alla; Ovcharenko, Alina; Usenko, Andrii Yu.; Pazynich, Yuliya
ENG: Modification of the properties of caking coals through the methods of their treatment is of practical interest, especially in the context of deterioration of the raw material source for coke production and high requirements for the quality of coke. Considering the hydrophobicity of coals and their relatively high porosity, vapor treatment can be an effective method of influencing coal properties. Research on the properties of coal treated with water vapor and crude benzene vapor was conducted using different caking ability methods. Coal moistened to 10%wt. was also investigated for comparison. Four coal samples with varying degrees of coalification, ranging from medium to high rank (Ro = 0.76–1.50%) and characterized by volatile matter (Vdaf = 20.24–37.42%), were investigated. The mechanisms of interaction between coals and water in liquid and vapor form were determined. The results demonstrate that the treatment with water vapor and crude benzene significantly affects the properties of coal A. Specifically, under the influence of water vapor, there is a decrease in the period before the formation of plasticity and an increase in the caking properties of coal A. Coal B and C have good caking ability, so the effect of treatment is less noticeable. The treatment of the coal D leads to an increase in the viscosity of the plastic mass and a decrease in the caking properties. The approaches used in the study of the impact on coal properties can be effectively implemented in production conditions.
Efficiency of Low-Calorific Fuel Use in Counterflow Lime Kilns
(D.A. Tsenov Academy of Economics, Svishtov, Bulgaria, 2023) Foris, Svitlana M.; Pererva, Valeriia Ya.; Usenko, Andrii Yu.; Foris, Oleksiy M.
ENG: Highly expensive energy carriers require revision of the existing engineering approaches in heating of industrial furnaces. The paper presents the results of research into the performance of a shaft kiln for lime-stone burning, which was fired with mixtures of natural gas and a fuel gas of a low calorific value. On the basis of studying various schemes of fuel distribution between the burners, the optimal operation mode of the kiln with reduced consumption of natural gas by 30% was identified. The lime quality indicators increase when the blast furnace gas is supplied to the central burner and improve when supplied to the peripheral burners. The joint supply of blast furnace gas in the calorific value section of the natural blast furnace mixture 9.4 ÷ 35 MJ/m3 allows keeping the performance of the furnace unchanged. At the same time, the coefficient of replacing natural gas with blast furnace gas is close to unity The proposed mode of heating the furnace with a capacity of 200 t/day with a natural blast furnace mixture provides 30% natural gas savings.
Electrically Heated Fluidized Bed for Graphite Purification: Heat Transfer and Electric Resistivity Models for Scale-Up
(Springer Nature, 2025) Ahmed, Imtiaz; Fedorov, Serhii S.; Sybir, Artem; Hubynskyi, Semen M.; Duchesne, Marc
ENG: Electrothermal purification is an effective method for achieving over 99.9 pct purity for graphite particles with minimal environmental impact. However, the lack of a suitable heat and electric resistivity model has hindered the scaling up of electrically heated fluidized bed (EHFB) reactors for graphite purification. In this study, three commercial natural graphite flake populations were tested in a bench-scale fluidized bed reactor at temperatures of up to 1000 °C. The experiments varied key parameters, including the graphite particle size, particle bed temperature, fluidization index, and electrode depth within the particle bed. Controlling the fluidized bed reactor at high temperatures requires an understanding of bed resistivity and how current flows throughout the EHFB system. The results show that fluidized bed resistivity decreases with temperature, with a diminished effect at higher temperatures. Smaller particles exhibit a higher resistance, likely due to a larger number of contact points required to pass current between the electrodes. In this study, a Finite Difference Method (FDM) model was developed using Visual Basic for Applications (VBA) in Excel®. Additionally, a Finite Element Method (FEM) model was created using COMSOL Multiphysics®. The FDM model assumes the current flows only radially, whereas the FEM model accounts for both radial and vertical current flow. The FDM model was validated against experimental data. Additionally, the FDM model was verified through a comparison with the FEM model. The FDM model showed good agreement with experimental resistance data and moderate agreement with power consumption, while the FEM model provided more accurate predictions by accounting for a detailed geometry and heat loss mechanisms. Achieving a uniform temperature distribution within the fluidized bed is influenced by the electrode’s contact area. Deeper immersion of the electrode enhances thermal uniformity and provides results that more closely match experimental observations.
Energy Efficient Water-Cooled Elements for Foundry Class Electric Arc Steelmaking Furnaces
(НМетАУ, Дніпро, 2021) Timoshenko, Sergii; Nemtsev, Eduard; Gubinskij, Mikhail
ENG: Analysis of recent research and publications. Low energy efficiency of foundry class electric arc steelmaking furnaces (EAF) mainly is caused by heat loss in massive refractory lining during forced downtime. A low-power transformer doesn’t allow, in the conditions of classical technology, practice of traditional water-cooled elements in order to replace partially the lining, what determines increased refractory consumption. Known mathematical models of heat and mass transfer in the EAF working space don’t pay sufficient attention to the features of thermal state and energy loss in water-cooled elements in relation to foundry class furnaces. Purpose. Work aims to improve energy efficiency and refractory savings in foundry class EAF due to water-cooled elements design improvement. Method. Work is based on numerical modeling of heat exchange by radiation in the working space of the EAF and thermal state of water-cooled elements with spatial structure. Research findings. On the base of radiation heat exchange study, a multiple regression equation for power of heat loss with cooling water was obtained, taking into account capacity of the furnace, steelmaking bath shape factor (diameter to depth ratio), duration of technological period of the heat and averaging coefficient of heat flux through working surface of water-cooled element. For traditional one-row, two- and elaborated three-row panels averaging coefficient is 0.82, 0.67 and 0.61, respectively. Practical significance. Three-row water-cooled wall panels with a spatial structure are elaborated, which provide a decrease in heat loss with cooling water by 14 %, in comparison with two-row ones and by 40% in comparison with traditional one-row panels with dense structure. Estimates of optimal relative cooled surface for 3-12-ton EAF working space, providing refractory savings up to 25-30% due to three-row water-cooled panels installation, are substantiated.
Energy-Efficient Solutions of Foundry Class Steelmaking Electric Arc Furnace
(Dnipro University of Technology, Dnipro, 2021) Timoshenko, S. M.; Gubinski, M. V.; Niemtsev, E. M.
ENG: Purpose. Substantiation of solutions aimed at reducing heat losses, mainly, by refractory lining during forced downtime and by steelmaking bath in conditions of traditionally low specific power of transformer. Methodology. Mathematical modeling of heat and mass transfer processes and numerical experiment. Findings. A mathematical model of energy-technological processes in arc furnace workspace has been developed to analyze and minimize energy consumption in daily production cycle. Geometrical and operating parameters are taken into account, in particular: variation in arcs energy efficiency at evolution of wells in charge under electrodes during melting process; circulation of melt due to bubbling with inert gas through bottom porous plug; energy loss on heat accumulation by refractory, with cooling water and off-gas. Originality. For the first time, the concept of increasing energy efficiency of arc furnace has been substantiated, based on the following set of solutions: increase in specific electrical power by reducing of charge at given productivity; reduction of bath shape factor (ratio of diameter to depth) from traditional 5 up to 2.5 by deepening and, accordingly, its radiating surface; optimization of walls and roof cooled surface relative area, where massive heat-absorbing refractory lining is not used; application of energy-saving water-cooled elements with spatial structure that promotes formation of heat-insulating and heat-accumulating slag filling. Practical value. Implementation of the set of energy-efficient solutions in conditions of typical 6 and 12-t foundry class arc furnaces provides reduction in power consumption and refractory expenditure by 1315 and 2830% respectively without significant changes in production infrastructure due to reducing energy loss, mainly, for accumulation of heat by refractory lining, and intensification of heat and mass transfer processes in forcibly stirred deep bath.
Environmental Engineering, Innovations, and Management. Editorial Review
(Begell House Inc., USA, 2023) Kuzmin, Andrey; Pinchuk, Valeriya A.
ENG: In recent years, special attention has been paid to environmental safety in various fields of application. Among all human activities, applications related to energy are always in high demand. At the same time, many of them affect climate change and can lead to biodiversity degradation and other environmental problems. The International Journal of Energy for a Clean Environment is a periodical that publishes high-quality research on the intersection of energy and the environment. The current issue of the journal presents the results obtained by researchers from different countries and different fields of research, devoted to some points in the field of energy and environmental management.
Hazard Modelling of Accidental Event in Urban Environment
(IOP Publishing Ltd, 2025) Biliaiev, Mykola M.; Kalashnikov, Ivan V.; Biliaieva, Viktoriia V.; Kozachyna, Vitalii A.; Kozachyna, Valeriia V.
ENG: This paper investigates the impact of accidental event at the gas station which is situated in Dnipro City. The processes of chemical and thermal air pollution were simulated on the basis of developed numerical models. To simulate chemical and thermal air pollution mass conversation equation and energy equation were used. For the numerical integration of governing equations finite difference schemes of splitting were used. Also, the process of fragments scattering which appears as the result of explosion at the gas station was modelled. To simulate fragments scattering Newton second Law was used. To solve the governing equation Euler’s method was used. Results of numerical experiments are presented.
Identifying Regularities in the Propagation of Air Ions in Rooms with Artificial Air Ionization
(PC TECHNOLOGY CENTER, 2023) Levchenko, Larysa; Burdeina, Nataliia; Glyva, Valentyn; Kasatkina, Natalia; Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Tykhenko, Oksana; Petrunok, Tetiana; Biruk, Yana; Bogatov, Oleg
ENG: The object of the study is the dynamics of air ion spread in rooms from the source of artificial air ionization under different starting conditions. There is currently the problem of distribution of air ions in the room with regulatory concentrations in all critical zones. An effective method of ensuring proper air ion concentrations is to model their propagation from ionization sources. Existing approaches to calculating the dynamics of air ions of both polarities have been improved in this study. Unlike known solutions, the impact on their concentration of electrostatic field and the interaction of air ions with suspended particles was taken into account. A model of air ion propagation in rooms with artificial air ionization and the principles of its numerical modeling was built. The use of Laplace Equation in the aerodynamic model instead of the Navier-Stokes equation for the potential of the flow rate has made it possible to design an "Ion 3D" tool, which reduces the time of implementation of one scenario from several hours to 7 seconds. Modeling of the propagation of air ions of both polarities in the room under different initial conditions was carried out. Two-dimensional and three-dimensional models with their visualization was implemented. The peculiarity of the resulting models is that they make it possible to determine the concentrations of air ions in any section of the room by three coordinates. Given this, the rapid selection of the variants of the source data makes it possible to achieve the normative values of concentrations of air ions in the area of breathing – exceeding 500 cm-3 of each polarity. Simulation makes it possible to design a room in which, under the condition of artificial ionization of air, the concentrations of air ions close to the optimal values of 3000–5000 cm-3 are provided.
Influence of an Electromagnetic Field on Direct Reduction of Iron Oxide Using Hydrogen as a Reducing Agent
(Wiley-Blackwell, USA, 2026) Levchenko, Mykyta; Gryshyn, Oleksandr M.; Velychko, Oleksandr H.; Grek, Oleksandr S.; Nadtochiy, Anzhela A.; Volkova, Olena
ENG: This work investigates the effect of electromagnetic fields (EMF) of varying frequencies on the reduction process of iron oxides and industrial iron ore in a hydrogen atmosphere using thermogravimetric analysis. Both extremely low-frequency (50 Hz) and middle-frequency (25 kHz) EMFs were found to increase the reduction degree and accelerate the reduction reaction compared with experiments without EMF. The application of extremely low-frequency EMF did not cause additional thermal heating of investigated samples. However, with middle-frequency EMF, heating of charged material was observed, which was effectively compensated for by the furnace's automatic power regulation. Experiments with industrial iron ore confirmed that EMF application had a positive effect on reduction process even above the Curie temperature, indicating that the effect is not governed by magnetic properties of iron. These findings demonstrate that EMF-assisted hydrogen reduction can enhance reaction kinetics and reduce hydrogen consumption, offering a promising pathway toward more energy-efficient and sustainable steelmaking.
Influence of Biocoke on Iron Ore Sintering Performance and Strength Properties of Sinter
(Dnipro University of Technology, Dnipro, Ukraine, 2022) Kieush, Lina; Koveria, Andrii; Boyko, Maksym M.; Yaholnyk, Maksym V.; Hrubiak, Andrii; Molchanov, Lavr; Moklyak, Volodymyr
ENG: Purpose. The research purpose is to substantiate the use of biocoke as a fuel in the iron ore sintering, as well as its influence on the performance and properties of the resulting sinter. To completely replace conventional coke breeze, biocoke is produced using 5 wt.% biomass wood pellets at different carbonization temperatures of 950 or 1100°C. Further, the influence of biocoke on the sintering process and the sinter quality is studied at a high proportion of biomass pellets of 10, 15, 30, 45 wt.% and a carbonization temperature of 950°C. Methods. Carbonization is performed in shaft-type electric furnaces to produce laboratory coke or biocoke. Afterward, the sintering of iron ores is conducted on a sinter plant. To assess the sintering process and the quality of the resulting sinter, the filtration rate is determined on a laboratory sinter plant using a vane anemometer designed to measure the directional flow average velocity under industrial conditions. The sinter reducibility is studied using a vertical heating furnace to assess the effect of coke and biocoke on the sinter’s physical-chemical properties. Findings. It has been determined that biocoke, carbonized at a temperature of 950°C, has good prospects and potential for a shift to a sustainable process of iron ore sintering. Originality. It has been proven that biocoke with a biomass pellet ratio of up to 15 wt.%, obtained at a temperature of 950°C, does not affect the parameters characterizing the sintering process. The sinter strength indicators correspond to the use of 100 wt.% conventional coke breeze. Biocoke used with a high proportion of biomass pellets of 30 and 45 wt.% causes a deterioration in the sinter quality. Practical implications. The results of using biocoke with the addition of 5-15 wt.% biomass pellets and at a temperature of 950°C are within the standard deviation, which makes it possible to use biocoke with 15 wt.% biomass pellets instead of industrial coke breeze.
Major Lessons Learnt from an Online Teaching of Automation and Control Courses during the Pandemic and the Way ahead: A Critical Interpretative Synthesis
(Public Organization "Ukrainian Assembly of Doctors of Sciences in Public Administration", Kyiv, Ukraine, 2023) Таrasevich, Iryna G.; Tarasevich, Alena V.; Foris, Svitlana M.; Kuzmenko, Mykhailo Y.
ENG: Covid-19 brought in adapted frameworks, concepts, and tools into the design and delivery of automation courses at technical universities. Although university digitalization has been around for a while, it has been used primarily for the administrative purpose rather than for teaching and learning. A natural, powerful stimulator, the pandemic pushed the universities to explore new avenues in further digitalization of education. The goal of this critical interpretive synthesis is to make a summary of the major lessons learnt from the online teaching of automation courses during the pandemic and their further implementation. It is also aimed at exploring major tensions and barriers that users (teaching faculty, students, and administrative personnel) have been grappling with. The tensions and barriers are presented in this paper from three distinct perspectives – from the perspectives of students, teaching faculty, and university administrators. Whether students thrive or survive, the faculty rethink and upskill their teaching, and the institution is capable of meeting multiple, often competing needs and shifting priorities of the market – warrants further research on the topic. An important question to be addressed in future inquiries is whether the stakeholders that are engaged in the process of developing, teaching, and taking an automation course, are able to reconceptualize their roles and continue to grow professionally.
Metallurgical Coke Production with Biomass Additives: Study of Biocoke Properties for Blast Furnace and Submerged
(MDPI, Switzerland, 2022) Bazaluk, Oleg; Kieush, Lina; Koveria, Andrii; Schenk, Johannes; Pfeiffer, Andreas; Zheng, Heng; Lozynskyi, Vasyl
ENG: Biocoke has the potential to reduce the fossil-based materials in metallurgical processes, along with mitigating anthropogenic CO2- and greenhouse gas (GHG) emissions. Reducing those emissions is possible by using bio-based carbon, which is CO2-neutral, as a partial replacement of fossil carbon. In this paper, the effect of adding 5, 10, 15, 30, and 45 wt.% biomass pellets on the reactivity, the physicomechanical, and electrical properties of biocoke was established to assess the possibility of using it as a fuel and reducing agent for a blast furnace (BF) or as a carbon source in a submerged arc furnace (SAF). Biocoke was obtained under laboratory conditions at final coking temperatures of 950 or 1100 °C. Research results indicate that for BF purposes, 5 wt.% biomass additives are the maximum as the reactivity increases and the strength after reaction with CO2 decreases. On the other hand, biocoke’s physicomechanical and electrical properties, obtained at a carbonization temperature of 950 °C, can be considered a promising option for the SAF.
Methodology for Modeling the Spread of Radioactive Substances in Case of an Emergency Release at a Nuclear Power Plant
(National Technical University «Kharkiv Polytechnic Institute», Kharkiv, 2023) Levchenko, Larysa; Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Ausheva, Nataliia; Tykhenko, Oksana
ENG: The methodology for modeling the propagation of accidental releases of radionuclides from a power unit of a nuclear power plant has been developed. The calculation method takes into account the most critical factors propagation cloud - wind direction and speed, the intensity of the release radionuclides change: semi-continuous release, long-term release, instantaneous release. Diffuse processes and the presence of interference in the form of buildings were also taken into account. To solve the modeling equation of the aerodynamic model, the velocity potential equation is solved. The use of this equation instead of the traditional Novier-Stokes equation makes it possible to rationalize the calculation process in terms of the speed obtaining simulated data. To build a numerical model, a rectangular difference grid is used. The velocity potential and the quantities values of volumetric activity are determined at the centers of difference cells. The value of the airflow velocity vector component is determined on the sides of the difference cells. A finite-difference splitting scheme is used for numerical integration of the equation convective-diffusion transfer radionuclides. A computer code was developed on the basis of the constructed numerical model, the programming language Fortran was used. The approach used makes it possible to reduce the time for obtaining one scenario of an accident development. The cloud propagation dynamics determining is carried out almost in real time. This allows you to quickly respond to changing situations and make adequate decisions.
Modeling Influence of TiO2 Barrier Coating on Pollutant Dispersion Near Road
(Kaunas University of Technology, 2023) Biliaiev, Mykola M.; Berlov, Oleksandr V.; Biliaieva, Viktoriia V.; Kozachyna, Vitalii A.; Kozachyna, Valeriia; Yakubovska, Zinaida M.
ENG: Mitigation strategies for near-road air pollution are of great interest nowadays. Sound barriers near the road are very effective to decrease pollutant concentration. The use of titanium dioxide (TiO2) barrier coating provides additional effect which allows to decrease pollutant concentration near road. In this study quick- computing CFD model was developed to access influence of TiO2 barrier coating on pollutant concentration. To simulate wind flow over barrier with TiO2 coating model of potential flow was used. The process of NOx dispersion from car was computed using mass conservation equation. Finite-difference schemes were used for numerical integration of governing equations. The computer code was developed on the basis of proposed numerical model. Results of numerical simulations are presented.
Modeling the Distribution of Emergency Release Products at a Nuclear Power Plant Unit
(Національний технічний університет "Харківський політехнічний інститут", 2024) Biliaieva, Viktoriia V.; Levchenko, Larysa; Myshchenko, Iryna; Tykhenko, Oksana; Kozachyna, Vitalii A.
ENG: Despite the fact that much attention is paid to the safe operation of nuclear power plants, there is a possibility of an accident with the release of radionuclides. This is especially true in Ukraine, where there is a threat of the damage to nuclear reactors as a result of military operations. It is impossible to research the distribution of products emergency releases radioactive substances in laboratory conditions. Therefore, the only tool for the development predicting of an accident is the modeling the spread of a radionuclides cloud. The purpose of the research is a modeling the distribution of emergency release products in a nuclear power plant unit, suitable for the operative assessment of a development an accident. Results of the research: The mathematical model of the distribution emission products of a nuclear power plant has been developed, which takes into account the value of the initial activity of emission products, the rate of the settling radioactive particles, the wind speed components, the intensity changes radionuclide emission over time. The technique for solving the boundary value problem of modeling in conditions of a complex shape of the computational domain, taking into account the presence of obstacles to the spread of emission products has been developed. The use of the velocity potential equation in evolutionary form allows us to speed up the calculation process. The chosen splitting scheme of an alternating-triangular method allows to find the speed potential according to the explicit form at each splitting step. This allowed software implementation of the CFD model. The visualized models of the emission cloud distribution allow to determine the radiation situation in any place of the emission product distribution zone. The developed model makes it possible to quickly predict the development of an accident in space and time, which makes it possible to take measures to protect people from exposure in the shortest possible time. Conclusions: The obtained emission cloud propagation models and their visualization make it possible to determine the state of environmental pollution under various initial conditions during the development of the accident.
Numerical Modeling of the Wind Regime on the Beaches of the Wash of the Artificial Storage Facilities for Mineral Processing Waste
(IOP Publishing, 2024) Lapshyn, Yevhen; Biliaiev, Mykola M. ; Biliaieva, Viktoriia V. ; Halchenko, Zariana; Medianyk, Volodymyr; Buketov, Valentyn
ENG: A 2D numerical model has been developed to estimate the airflow velocity field when flowing around the dam of an artificial storage facility for mineral processing waste. To solve the aerodynamic problem of determining the air flow velocity field when flowing around such hydraulic structures with a complex geometric shape, a potential motion model was applied. The numerical integration of the equation for the velocity potential is carried out using the Liebman method. The geometric shape of the tailings storage facility is formed in a discrete model using the marking method. A computer program was created to implement the developed numerical aerodynamics model. Based on the processing of the results of computational experiments, coefficients were obtained that allow us to quickly determine the value of the air flow velocity at the beginning and end of the tailing pond beach, i.e. in the area of the most intense dust emission. This allows for a quick prediction of the risk of dust air pollution at different tailing pile heights.
Numerical Models in Applied Problems of Heat and Mass Transfer
(Ukrainian State University of Science and Technologies, 2025) Biliaieva, Viktoriia V.; Shcherbyna, Serhii
ENG: Purpose. The problems of farm ventilation, prediction of CO concentration fields inside farms, prediction of artificial soil heating in greenhouses are considered. To solve a complex of such problems, it is necessary to have specialized mathematical models, oriented towards users in design organizations. Development of numerical models for solving heat and mass transfer problems for agricultural facilities (farms, greenhouses). Methodology. To solve the problem of ventilation of the working room (determination of the air flow velocity field in the room), a mathematical model of the motion of a vortex-free flow of an inviscid fluid (Laplace equation for the velocity potential) is used. Numerical integration of the modeling equation is carried out using two schemes: a locally one-dimensional scheme and a conditional approximation scheme. The G. Marchuk model is used to model the mass transfer process. Splitting schemes are used for numerical integration of the modeling equation. Two numerical models are built to analyze thermal fields in a stationary environment: a two-dimensional energy equation and a one-dimensional energy equation. Two difference schemes are used for numerical integration of the two-dimensional energy equation: a conditional approximation scheme and an explicit finite-difference scheme. An implicit splitting scheme is used to solve the one-dimensional energy equation. Findings. The software implementation of the developed numerical models has been carried out. The results of computational experiments are presented. Originality. Effective mathematical models and computer codes have been developed for solving problems of aerodynamics and mass transfer in the working space, as well as the process of heat conduction in a stationary environment. The created numerical models belong to the class of "diagnostic models", that is, computer codes that implement the developed numerical models make it possible to quickly obtain estimated data on thermal or concentration fields in the study area. Practical value. The created computer codes can be used to analyze thermal and concentration fields in agricultural premises (greenhouses, farms) to analyze the efficiency of energy systems and ensure the necessary ventilation and heating modes of the environment.
Numerical Simulation of Pollutant Dispersion from Road with Barrier
(IOP Publishing Ltd, 2025) Biliaiev, Mykola M.; Kalashnikov, Ivan V.; Biliaieva, Viktoriia V.; Kozachyna, Vitalii A.; Kozachyna, Valeriia V.
ENG: The impact of protective barriers on air pollution dispersion near the road was examined using developed numerical model. To simulate wind flow over barrier model of potential flow was used. To simulate pollutant dispersion from road convective-diffusive equation was used. Difference schemes of splitting were used for numerical integration of governing equations. Dispersion of pollutant was modeled for scenarios with no barrier near the road, vertical solid barrier, vertical barriers with additional elements, combination “vertical barrier and plate on the pavilion”. To estimate the efficiency of each scenario potential hazard risk indicator was used. Results of numerical experiment are presented.
Peculiarities of High-Temperature Refining of Carbon Materials
(Ukrainian State University of Chemical Technology, Dnipro, 2023) Sybir, A. V.; Hubynskyi, Semen M.; Fedorov, Serhii S.; Sukhyy, Kostyantyn M.; Hubynskyi, M. V.; Vvedenska, T. Y.
ENG: The purpose of the study was to determine the influence of the main following factors on the efficiency of the process of high-temperature refining of natural and artificial graphite: processing temperature, distribution of metal oxides, and changes in the aggregate state of ash impurities. Thermal processing of natural graphite from Ukrainian deposits and anthracite from Donetsk coal basin was carried out in a chamber furnace at a holding time of 10–20 minutes in a temperature range of 1500–30000 Ñ. The quality of refining was carried out by ICP-OES and XRF analysis methods. It was established that the refining process may be divided into three following periods: 0–16000 Ñ (removal of moisture, volatiles, and decomposition of carbonates); 1600–26000 Ñ (evaporation of main ash-forming metals Fe, Si, Al, Ca, Mg in the form of oxides, silicides, and carbides); and 2600–30000 Ñ (evaporation of refractory compounds Ti, V, Mo, the content of which in the initial raw material determines the processing temperature and the quality of the final product). The distribution of metal oxides in the initial carbon material is not uniform, which complicates the use of equilibrium state models. The transition of ash into the liquid and then gaseous state has a significant impact on the result of heat treatment. This is what determines the choice of the process scheme. Intermittent process is the heating by an external heater in an inert gas environment. Continuous process is the heating of the material in moving containers or processing in an electrothermal fluidized bed.
Phenomena at Three-Phase Electroslag Remelting
(Springer Nature, 2021) Liu, Zhong-li; Medovar, Lev; Stovpchenko, Ganna; Petrenko, Volodymyr; Sybir, Artem; Volchenkov, Yev.
ENG: The electroslag remelting (ESR) process is widely used to produce high-quality ingots and billets for high-alloyed steels and alloys. Both the single-phase and three-phase alternating current diagram with bifilar and monofilar connection are in use for heavy ingot manufacturing. The numerical simulation of the three-phase bifilar circuit for the 120 t three-phase bifilar six-electrode ESR furnace at different variants of electric connection was presented and discussed. At the bifilar diagram of power supply, the geometrical location of electrodes in a mould holds critical importance for performances: the close location of bifilar pair electrodes provides the highest heat productivity, but the equidistant location of electrodes gives a much more uniform heat distribution. The monofilar mulit-electrode diagram of three-phase connection without phase shift shows the most uniform distribution of potential and heat generation as well as a favorable magnetic field that makes this kind the most promising for providing a high quality of heavy ingots.
Prediction of Atmospheric Air Pollution Near a Coal Stack in Adverse Weather Conditions
(IOP Publishing Ltd, 2023) Biliaieva, Viktoriia V.; Berlov, Oleksandr V.; Kozachyna, Vitalii A.; Nochvai, Volodymyr; Yakubovska, Zinaida M.; Oladipo, Mutiu Olatoye
ENG: Coal piles on the territory of enterprises are long-term sources of dust pollution of atmospheric air. Forecasting the level of dust pollution of the air for such objects is carried out, as a rule, for convection conditions. But during inversion, very high concentrations of dust can occur on industrial sites. The task of assessing the level of dust pollution of atmospheric air at an industrial site during dust emission in conditions of inversion from a coal stack is considered. A three-dimensional equation of convective-diffusion dispersion of contamination in atmospheric air, compatible with the approach of Prof. Berliand M. on determining the value of the vertical diffusion coefficient in the surface layer of the atmosphere for the case of inversion, to model dispersion of dust from a coal stack under inversion conditions is used. Numerical integration of the modeling equation of convective-diffusion transport of contamination is carried out on the basis of the splitting method compatible with the use of a locally one-dimensional finite-difference scheme. The results of a computational experiment to determine dust pollution zones at the Prydniprovsk thermal power station are presented.
Production of Iron Ore Pellets by Utilization of Sunflower Husks
(Technical University of Košice, Slovakia, 2021) Kieush, Lina; Boyko, Maksym; Koveria, Andrii; Yaholnyk, Maksym; Poliakova, Natalia
ENG: Steel production is the most dynamic industry and one of the key sectors for developing the global economy. The growing iron ore production increases its beneficiation and granulating for subsequent iron and steel production use. As a result, CO2 emissions and harmful substances increase, negatively affecting society and the environment. In this regard, it is important to study the use of biomass for the production of iron ore pellets. Lignocellulosic biomass is a renewable and sustainable source of heat and energy that can mitigate climate change. The influences of alternative fuel use on technological indicators of the process and quality of iron ore pellets have been analyzed. The efficiency of using 40.4-60.7 vol.% of sunflower husks on the combined machine “straight grate - rotary kiln - annular cooler” to partially replace natural gas in iron ore pellets production under industrial conditions has been studied. It was found that the combustion of sunflower husks generates enough heat (19.31 MJ kg−1) to obtain iron ore pellets with good strength. After evaluating the parameters of the combined machine and the quality of the resulting pellets, it was determined that it would be rational to replace up to 48.3 vol.% of natural gas with crushed sunflower husks.
Quick computing CFD model to predict chemical pollution in room
(Український державний університет науки і технологій, Дніпро, 2024) Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Berlov, Oleksandr V.; Kozachyna, Vitalii A.; Mashykhina, Polina B.
ENG: Purpose. The problem of accidental contamination of workspaces attracts special attention, since in the event of such extreme situations, intense chemical contamination of the air in work areas occurs. This poses a threat of toxic exposure to workers. When assessing the consequences of such situations, it is necessary to take into account the time factor, in particular, to quickly determine the creation of concentrations of chemically hazardous substances. In this regard, an urgent task is to develop effective mathematical models for rapid assessment of the consequences of extreme situations in the working areas of chemically hazardous facilities. The paper considers a CFD model for analyzing the process of chemical air pollution in a workspace during an accidental release of a chemically hazardous substance. The solution of the problem is based on the numerical integration of the fundamental equations of continuum mechanics. Methodology. To calculate the air velocity field in the working room during the operation of supply and exhaust ventilation, a mathematical model of the motion of an inviscid fluid was used. The equation of convective diffusion motion was used to calculate the concentration of a chemically hazardous substance in the workspace. The integration of the modeling equations was carried out using finite difference schemes. Findings. A dynamic model has been created to calculate the spread of a chemically hazardous substance in a work-space. On the basis of the built CFD model, a computer program was created to conduct a computational experiment. Originality. A CFD model has been created to predict the level of air pollution in a workspace in the event of toxic gas emissions. The model is based on the fundamental equations of aerodynamic mechanics and mass transfer. The model makes it possible to determine the effect of the ventilation mode, the intensity of emission of a chemically hazardous substance, the location of equipment in the workspace, and the dynamics of the formation of concentration fields. Practical value. The developed CFD model can be used to quickly analyze the consequences of accidental emissions of a chemically hazardous substance in a workplace and assess the risk of toxic exposure of workers.
Simulation of Chemical Accident with Ammonia at the Pipe Line
(Kaunas University of Technology, 2023) Biliaiev, Mykola M.; Berlov, Oleksandr V.; Biliaieva, Viktoriia V.; Kozachyna, Vitalii A.; Kozachyna, Valeriia; Mashykhina, Polina B.
ENG: Ammonia is transported through Ukraine via the Togliatti-Odesa ammonia pipeline. The hostilities in Ukraine pose a risk of damage to this transportation system as a result of a shell, mine, etc. hitting the transportation system. Therefore, it is very important to predict the possible consequences of environmental pollution in the event of such an extreme situation. A numerical model was developed to solve this problem. The three-dimensional equation of convective-diffusive transport of an impurity in the atmosphere is used to predict the dynamics of pollution of atmospheric air and the underlying surface. Finite-difference splitting schemes are used to numerically integrate this equation. On the basis of the constructed numerical model, a computer code was developed to take into account the change in the intensity of ammonia leakage from the damaged pipeline. The results of a computational experiment are presented.
Structurally Dependent Electrochemical Properties of Ultrafine Superparamagnetic ‘Core/Shell’ γ-Fe2O3/Defective α-Fe2O3 Composites in Hybrid Supercapacitors
(MDPI, Switzerland, 2021) Bazaluk, Oleg; Hrubiak, Andrii; Moklyak, Volodymyr; Moklyak, Maria; Kieush, Lina; Rachiy, Bogdan; Gasyuk, Ivan; Yavorskyi, Yurii; Koveria, Andrii; Lozynskyi, Vasyl; Fedorov, Serhii S.
ENG: The paper presents a method for obtaining electrochemically active ultrafine composites of iron oxides, superparamagnetic ‘core/shell’ γ-Fe2O3/defective α-Fe2O3, which involved modifying sol-gel citrate synthesis, hydrothermal treatment of the formed sol, and subsequent annealing of materials in the air. The synthesized materials’ phase composition, magnetic microstructure, and structural, morphological characteristics have been determined via X-ray analysis, Mossbauer spectroscopy, scanning electron microscopy (SEM), and adsorption porometry. The mechanisms of phase stability were analyzed, and the model was suggested as FeOOH → γ-Fe2O3 → α-Fe2O3. It was found that the presence of chelating agents in hydrothermal synthesis encapsulated the nucleus of the new phase in the reactor and interfered with the direct processes of recrystallization of the structure with the subsequent formation of the α-Fe2O3 crystalline phase. Additionally, the conductive properties of the synthesized materials were determined by impedance spectroscopy. The electrochemical activity of the synthesized materials was evaluated by the method of cyclic voltammetry using a three-electrode cell in a 3.5 M aqueous solution of KOH. For the ultrafine superparamagnetic ‘core/shell’ γ-Fe2O3/defective α-Fe2O composite with defective hematite structure and the presence of ultra-dispersed maghemite with particles in the superparamagnetic state was fixed increased electrochemical activity, and specific discharge capacity of the material is 177 F/g with a Coulomb efficiency of 85%. The prototypes of hybrid supercapacitor with work electrodes based on ultrafine composites superparamagnetic ‘core/shell’ γ-Fe2O3/defective α-Fe2O3 have a specific discharge capacity of 124 F/g with a Coulomb efficiency of 93% for current 10 mA. View Full-Text.
Study of Cellulose Additive Effect on the Caking Properties of Coal
(Dnipro University of Technology, Dnipro, Ukraine, 2023) Koveria, Andrii; Kieush, Lina; Usenko, Andrii Yu.; Sova, Artem
ENG: Purpose. The work aims to study the effect of cellulose on the caking properties of various types of coking coal used in coking blends. The change in caking abilities has been analyzed to achieve the aim using standard techniques. At the same time, the effect of biomass additives on the plastic properties of coal has been analyzed comprehensively; the optimal amount of additive for practical purposes has been determined. Methods. Multiple coal characteristics in the plastic stage have been studied using a dilatometric method, the enhanced swelling pressure method, the plastometric method, and the Roga index test. The first three methods make it possible to characterize the caking properties of coal; and the Roga index test characterizes its coking ability. Findings. It has been identified that the optimal amount of biomass additive to study the effect on the properties of coal in the plastic state is more than 5 wt. %. In the paper, experimental dependences of the 5 wt. % cellulose addition influence on the caking properties of four coal grades have been obtained. The results showed a slight decrease in caking properties in terms of swelling, swelling pressure, thickness of the plastic layer, and caking ability. Simultaneously, the most sensitive methods for assessing the effect of cellulose addition on the coal plastic properties are the dilatometric method as well as the enhanced method for the swelling pressure determination. Originality. A comprehensive study of the effect of pure cellulose as a component of lignocellulose biomass on the properties of different coal grades in the plastic state (i.e. caking prperteis) has been carried out. A slight change in the coal properties in the plastic state with adding 5 wt. % cellulose, decreasing caking properties, has been shown. An important, not previously reported, conclusion is that the cellulose additive does not have any noticeable effect on the physical properties of the coal charge owing to its loose structure. Practical implications. A slight change in the caking properties of coal has been established with the addition of 5 wt. % which is of practical importance for the preparation of coal blends, and the coke production in the cases of using additives of lignocellulosic biomass without losing its quality. Additionally, renewable additive use while obtaining fuels and reducing agents is an approach to mitigate the negative environmental impact.
Walnut Shells as a Potential Fuel for Iron Ore Sintering
(Trans Tech Publications Ltd, Switzerland, 2021) Kieush, Lina; Koveria, Andrii; Boyko, Maksym; Hrubyak, Andrii; Sova, Artem; Yefimenko, Vadym
ENG: Purpose. Iron ore sintering is a predominant process for fine iron ore and its concentrate to be applied in the blast furnace process. However, sintering produces a negative impact on the environment. One of the effective ways to reduce greenhouse gas emissions from iron ore sintering is to use CO2-neutral biomaterials for the fuel needs of this technology. Walnut shells (WNS) are a promising raw material for such fuel substitute. Herein, the effect of the raw and the pyrolyzed WNS with a constant fineness of 3-0 mm on the sintering process and the sinter properties were studied. The proportion of WNS in the fuel composition was set to 25 wt.%. It has been established that the use of WNS pyrolyzed up to 873 K is optimal. Additionally, the difference in the reactivity of WNS and coke breeze has provoked the studies on the influence of the pyrolyzed WNS size on the sintering process. WNS size was set to 1-0, 3-0, 5-0, and 7-0 mm. It has been found that the most optimal both for the iron ore sintering process and the sinter quality is the use of WNS with a particle size of 3-0 mm, subjected to preliminary pyrolysis up to 873 K.
Біометан у когенераційних установках для автономного енергопостачання агропромислових об’єктів
(Видавничий дім «Гельветика», 2026) Усенко, Андрій Юрійович; Форись, Світлана Миколаївна; Біляєва, Вікторія Віталіївна
UKR: Актуальність дослідження зумовлена необхідністю підвищення енергетичної автономності агропромислових об’єктів в умовах зростання вартості енергоресурсів і вразливості централізованих систем енергопостачання. Агропромисловий сектор України характеризується значною енергоємністю та наявністю органічної сировини, що створює передумови для використання біометану в автономних когенераційних системах. Метою статті є обґрунтування доцільності використання біометану в когенераційних установках автономного енергопостачання агропромислових об’єктів з урахуванням реальних режимів електричного і теплового навантаження. Дослідження виконано з використанням розрахункового аналізу параметрів когенераційних установок на біометані, узагальнення технічних характеристик газопоршневого обладнання та застосування критеріїв енергетичної й економічної ефективності. Аналіз проводився для установок електричною потужністю 0,5–5,0 МВт із часткою утилізації теплової енергії 60–90% та регулюванням навантаження в діапазоні 50–100% номінальної потужності. Установлено, що за повного залучення теплової енергії сумарний коефіцієнт корисної дії когенераційних установок на біометані сягає 85–92%, тоді як за зниження коефіцієнта використання тепла нижче 60% ефективність когенерації істотно зменшується. Показано, що економічно прийнятні режими автономного енергопостачання відповідають строку окупності інвестицій до 6–7 років. Виявлено ключові обмеження, пов’язані з якістю біометану, сезонною нерівномірністю теплових навантажень і необхідністю адаптивного керування режимами генерації. Наголошено, що біометан може слугувати ефективною паливною основою автономних когенераційних систем агропромислових об’єктів за умови стабілізації параметрів палива та узгодження потужності установки зі структурою енергоспоживання підприємства. Подальші дослідження доцільно спрямувати на розроблення адаптивних алгоритмів управління когенераційними установками на біометані, удосконалення технологій очищення палива та деталізацію економічної оцінки автономних енергетичних систем за повним життєвим циклом.
Визначення механічних властивостей синтетичних чавунів при використанні карбюризаторів отриманих на основі електротермічного киплячого шару
(Інститут чорної металургії ім. З. І. Некрасова НАН України, Дніпро, 2024) Губинський, Михайло Володимирович; Меркулов, Олексій Євгенович; Сибір, Артем Віталійович; Федоров, Сергій Сергійович; Губинський, Семен Михайлович; Форись, Олексій Михайлович; Дудченко, Сергій Олександрович; Джигота, Марина Георгіївна
UKR: Розвиток високотемпературних технологій у металургії та хімічній галузі пов’язаний з заміною викопних видів палива на зелену електроенергію. Саме таку можливість має процес нагріву вуглецевої сировини у електротермічному киплячому шарі (ЕКШ) коли струм проходить безпосередньо через шар і нагріває його за рахунок джоулевої теплоти. Такий процес дозволяє значно зменшити витрати енергії порівняно з традиційними технологіями, що базуються на використанні печей Аченсона та Кастнера. Одним з продуктів що може бути отриманий в печах ЕКШ є карбюризатори що використаються при виплавці синтетичного чавуну. Проведені дослідження дозволили визначити властивості до карбюризаторів, що забезпечують якість чавунів та параметри термічної обробки прекурсорів у ЕКШ. Метою даного дослідження було отримання прямої відповіді про ефективність карбюризаторів отриманих за новою технологією. Вирішення цього завдання проведено шляхом порівняльних випробувань карбюризаторів отриманих методом ЕКШ та традиційними технологіями при отриманні синтетичного чавуну. Випробування проведені з використанням лабораторної індукційної печі ємністю 10 кг. Плавки було проведено в ідентичних умовах. В результаті доведено що процеси навуглецювання чавуну з карбюризатором отриманим по новій технології та синтетичним графітом мають східні температурні та кінетичні залежності. Ступінь засвоєння вуглецю практично однакові. Металографічний аналіз отриманих зразків синтетичного чавуну показав, що виливки отримані з використанням синтетичного графіту характеризуються більшою кількістю пор, що може бути причиною зниження механічних властивостей. Результати випробувань на стиск, розтягнення, вигин та твердість підтвердили це. Отримані результати випробувань довели ефективність вироблення карбюризаторів високої якості з використанням технології ЕКШ.
Вуглецевотермічне відновлення оксидів заліза в умовах електромагнітного впливу
(НМетАУ, УДУНТ, Дніпро, 2024) Гришин, Олександр Михайлович; Величко, Олександр Григорович; Грек, Олександр Сергійович; Надточій, Анжела Анатоліївна
UKR: Мета. З метою отримання кількісних характеристик впливу електромагнітного поля на процес відновлення оксидів заліза вуглецем у твердій фазі та вивчення механізму цього процесу проведено експериментальні дослідження вуглецевотермічного та комплексного відновлення заліза з гематиту, магнетиту та окалини. Методика. Експерименти проводили у змінному магнітному полі індукційної печі з частотою змінного току в індукторі від 50 Гц до 40 кГц. з використанням термогравіметричної методики. Процес відновлення моделювали в умовах вуглецевотермічного відновлення із визначенням кінцевого ступеню відновлення оксиду та часу відновлення у діапазоні температур 973-1373 К з використанням різних рудо-вугільних матеріалів. Результати. Отримані дані свідчать про прискорення процесів газифікації вуглецю та газового відновлення оксидів під впливом ЕМП на 10-20 %. Встановлено що вплив магнітного поля тим вищий чим вище частота змінного струму в індукторі печі а також що вплив магнітного поля вищий у низькотемпературних діапазонах відновлення. Наукова новизна. Експериментально підтверджено вплив ЕМП на кінетику відновлення оксидів заліза. Запропоновано механізм впливу поля що інтенсифікує процес відновлення заліза. Практична значущість. Інтенсифікація процесів вуглецевотермічного відновлення оксидів заліза забезпечує зниження енерговитрат та підвищення продуктивності процесу.
Відновлювана енергетика як чинник скорочення викидів парникових газів в Україні в умовах енергетичної трансформації
(Sergeieva&Co, Karlsruhe, Germany, 2025) Перерва, Валерія Яківна; Усенко, Андрій Юрійович; Форись, Світлана Миколаївна; Максимчук, Сергій
UKR: У статті досліджено актуальні проблеми розвитку відновлюваних джерел енергії та виклики, пов’язані зі зростанням викидів парникових газів в енергетичному секторі України. Основними труднощами є вимушена децентралізація енергетичної системи через відмову від великих енергогенерувальних об’єктів і скорочення обсягів електрогенерації, що зумовлює більшу потребу в автономних джерелах енергії. Оцінка взаємозв’язку між відновлюваними джерелами енергії та рівнем викидів парникових газів ускладнюється їх різноманітністю, відмінною енергоємністю та дією нових чинників, зокрема бойових дій, які створюють додаткові джерела забруднення. Наголошено на необхідності подальших досліджень впливу руйнівних факторів на оновлення енергетичних технологій і прискорення впровадження інноваційних рішень для зменшення викидів парникових газів. Встановлено, що для зниження екологічного навантаження потрібен перехід до децентралізованої енергетики із залученням відновлюваних джерел. Проте досвід України вказує на доцільність використання гібридних технологій, які демонструють вищу стійкість до негативних факторів. Повна відмова від невідновлюваних джерел не є доречною. Для досягнення сталого розвитку пріоритетними є підвищення енергоефективності на всіх етапах – від виробництва до споживання енергії, формування екологічної свідомості населення та впровадження інноваційних технологій у сферу енергетики. Перспективи застосування результатів дослідження полягають у визначенні найбільш ефективних технологій для енергетичного сектору в умовах кризи, а також у розробленні заходів для підвищення енергетичної стійкості, незалежності та гарантування екологічної безпеки держави.
Геотермальні теплові насоси з багатоконтурними ґрунтовими полями для автономного теплопостачання кампусів
(Видавничий дім «Гельветика», 2025) Форись, Світлана Миколаївна; Усенко, Андрій Юрійович; Шемет, Т. М.
UKR: Актуальність дослідження зумовлена необхідністю трансформації кампусних інфраструктур до низьковуглецевих, автономних та високоефективних систем теплопостачання, у яких використання геотермальних теплових насосів з багатоконтурними ґрунтовими полями розглядається як одне з найперспективніших рішень. З огляду на високу сезонну та добову мінливість теплових навантажень сучасних кампусів і значну неоднорідність геологічних умов виникає потреба у науковому обґрунтуванні оптимальних параметрів проєктування та експлуатації таких систем. Мета статті полягає у науковому обґрунтуванні інженерних принципів проєктування та раціональних режимів експлуатації геотермальних теплових насосів із багатоконтурними ґрунтовими полями з урахуванням теплофізичних властивостей ґрунту, динаміки теплового навантаження кампусу та вимог енергоефективності. Методи дослідження включають системний аналіз теплофізичних параметрів ґрунтових масивів, моделювання довготривалої динаміки температурних полів, структурно-технологічний аналіз роботи теплових насосів у змінних режимах та оцінювання техніко-експлуатаційних умов інтеграції геотермальних установок у теплові мережі кампусу. Застосовано аналітичне порівняння конфігурацій багатоконтурних полів і параметрів їх взаємодії з тепловими насосами, а також проведено аналіз світової практики функціонування подібних систем. У результаті проведеного дослідження встановлено закономірності формування та еволюції температурного поля багатоконтурних ґрунтових масивів, доведено визначальну роль теплопровідності, вологості й геометрії контурів у забезпеченні стабільної тепловіддачі. Обґрунтовано критичний вплив температури теплоносія на вході, гідравлічного балансування та динаміки теплового опору ґрунту на сезонну ефективність теплових насосів. Виявлено техніко-експлуатаційні умови для успішної інтеграції геотермальних систем у теплову інфраструктуру кампусу та визначено основні проблеми довготривалої стійкості багатоконтурних полів, зокрема деградацію теплового потенціалу, геологічну неоднорідність і територіальні обмеження. У висновках доведено, що поєднання багатоконтурної структури ґрунтових полів з інтелектуальними стратегіями керування, резервуванням критичних елементів та застосуванням низькотемпературних внутрішніх мереж формує передумови для забезпечення автономного, стабільного та енергоощадного теплопостачання кампусів у довгостроковому періоді. Перспективи подальших досліджень пов’язані з такими напрямами: розробленням точніших моделей термогідродинаміки ґрунтових масивів, удосконаленням методик визначення оптимальної щільності свердловин на обмежених територіях та інтеграцією геотермальних систем у мультиджерельні енергетичні комплекси нового покоління.
Декарбонізоване автономне теплопостачання кампусів із використанням геотермальних теплових насосів
(Sergeieva&Co, Karlsruhe, Germany, 2025) Усенко, Андрій Юрійович; Форись, Світлана Миколаївна; Форісь, Юрій М.
UKR: Актуальність дослідження зумовлена необхідністю трансформації кампусних інфраструктур до низьковуглецевих, автономних та високоефективних систем теплопостачання, у яких використання геотермальних теплових насосів з багатоконтурними ґрунтовими полями розглядається як одне з найперспективніших рішень. З огляду на високу сезонну та добову мінливість теплових навантажень сучасних кампусів і значну неоднорідність геологічних умов виникає потреба у науковому обґрунтуванні оптимальних параметрів проєктування та експлуатації таких систем. Мета статті полягає у науковому обґрунтуванні інженерних принципів проєктування та раціональних режимів експлуатації геотермальних теплових насосів із багатоконтурними ґрунтовими полями з урахуванням теплофізичних властивостей ґрунту, динаміки теплового навантаження кампусу та вимог енергоефективності. Методи дослідження включають системний аналіз теплофізичних параметрів ґрунтових масивів, моделювання довготривалої динаміки температурних полів, структурнотехнологічний аналіз роботи теплових насосів у змінних режимах та оцінювання технікоексплуатаційних умов інтеграції геотермальних установок у теплові мережі кампусу. Застосовано аналітичне порівняння конфігурацій багатоконтурних полів і параметрів їх взаємодії з тепловими насосами, а також проведено аналіз світової практики функціонування подібних систем. У результаті проведеного дослідження встановлено закономірності формування та еволюції температурного поля багатоконтурних ґрунтових масивів, доведено визначальну роль теплопровідності, вологості й геометрії контурів у забезпеченні стабільної тепловіддачі. Обґрунтовано критичний вплив температури теплоносія на вході, гідравлічного балансування та динаміки теплового опору ґрунту на сезонну ефективність теплових насосів. Виявлено техніко-експлуатаційні умови для успішної інтеграції геотермальних систем у теплову інфраструктуру кампусу та визначено основні проблеми довготривалої стійкості багатоконтурних полів, зокрема деградацію теплового потенціалу, геологічну неоднорідність і територіальні обмеження. У висновках доведено, що поєднання багатоконтурної структури ґрунтових полів з інтелектуальними стратегіями керування, резервуванням критичних елементів та застосуванням низькотемпературних внутрішніх мереж формує передумови для забезпечення автономного, стабільного та енергоощадного теплопостачання кампусів у довгостроковому періоді. Перспективи подальших досліджень пов’язані з такими напрямами: розробленням точніших моделей термогідродинаміки ґрунтових масивів, удосконаленням методик визначення оптимальної щільності свердловин на обмежених територіях та інтеграцією геотермальних систем у мультиджерельні енергетичні комплекси нового покоління.