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Item type:Item, 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, PavloENG: 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.Item type:Item, 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.Item type:Item, 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.Item type:Item, Evaluation of Gabions Usage Effectiveness for Industrial Facilities Protection Against Damage(Український державний університет науки і технологій, Дніпро, 2025) Medvedieva, Olha O.; Dziuba, Serhii V.; Kalashnikov, Ivan V.; Biliaiev, Mykola M.; Kozachyna, Vitalii A.ENG: 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.Item type:Item, Experimental Study of Dust Emission Intensity from the Surface of the Alluvium Beach(IOP Publishing, 2024) Medvedieva, Olha O. ; Biliaiev, Mykola M.; Kozachyna, Vitalii A.; Mormul, Taras; Buketov, ValentynENG: The paper presents data on the current state of waste storage facilities of mining and processing plants in Kryvyi Rih. They are complex, environmentally hazardous hydraulic structures. When assessing the extent of dust pollution from tailing ponds, it is extremely important to know the intensity of dust emissions from the surface of the alluvium beach. This parameter is the basic one in all prognostic models used to predict environmental pollution. The paper presents the results of experimental studies to determine the wind speed at which the removal of dry dust particles from the surface of the beach of a tailing pond begins, as well as the intensity of dust removal from the surface of the beach for dry sand and wet sand. The experimental studies conducted in the laboratory allowed obtaining data on the intensity of dust emission from the surface of the tailing dump beach. The results obtained by the authors make it possible to more accurately assess the degree of environmental dustiness using predictive models. Тhe data on determining the intensity of dust formation for sand of different moisture content will be useful for determining the effectiveness of dust suppression by supplying water to the beach surface.Item type:Item, Experimental Study of the Intensity of Coal Dust Removal(Prydniprovs'ka State Academy of Civil Engineering and Architecture, Dnipro, Ukraine, 2023) Biliaiev, Mykola M.; Berlov, Oleksandr V.; Brazaluk, Yuliia V.; Kozachyna, Vitalii A.; Oladipo, Mutiu OlatoyeENG: Problem statement. Industrial sites where coal storages are located are intensive sources of dust pollution of the environment. There is an important problem of assessing the intensity of dust removal into the atmospheric air from polluted areas. Knowledge of the intensity of dust removal into the atmospheric air makes it possible to scientifically assess the impact of contaminated sites on the pollution of the environment and work zones at industrial sites. The solution to this problem can be obtained experimentally. The purpose of the article. An experimental study of the value of the air flow velocity at which the detachment of dust particles from the surface with coal begins and their removal into the air and the determination of the intensity of the emission of coal dust from the contaminated surface. Methodology. The intensity of removal of coal dust from the contaminated area was studied experimentally in laboratory conditions. The research was conducted on coal samples from DTEK “Pavlohradvuhillya”, grade “ДГ. During the research, the velocity of the air flow at which the process of movement of dust particles along the emission source began and the velocity of “detachment” of dust particles and their removal from the emission source were determined. At the second stage of experimental research, the intensity of removal of coal dust from the polluted area was determined. Scientific novelty. The values of the air velocity at which the removal of coal dust particles from the contaminated area begins were determined experimentally. The regularity of the intensity of the removal of coal dust depending on the velocity of the air flow over the contaminated area was obtained. Practical significance. The obtained experimental data make it possible to determine under which weather conditions there is a risk of dust formation and the removal of dust into the atmosphere. The empirical dependence obtained by processing experimental data can be used for a scientifically based assessment of the level of pollution of working areas at industrial sites where there are coal storage facilities. Conclusions. The value of the velocity of the air flow at which the movement of dust particles on the contaminated surface begins, as well as the value of the velocity of the air flow at which the removal of dust particles into the air begins, was determined experimentally. The resulting empirical model can be used to estimate environmental damage due to dust pollution of atmospheric air.Item type:Item, Forecasting Zones of Air Pollution from Solid Waste Landfills(Український державний університет науки і технологій, Дніпро, 2025) Medvedieva, Olha O.; Dziuba, Serhii V.; Biliaiev, Mykola M.; Kozachyna, Vitalii A.; Kirichenko, Pavlo S.ENG: Purpose. The work is aimed at developing a mathematical model that allows to quickly calculate the area of chemical air pollution during the emission of hazardous substances from solid waste landfills. The mathematical model takes into account meteorological parameters, geometric shape of the landfill, intensity of emission of hazardous substances from the landfill. Methodology. The two-dimensional equation of convective diffusion transfer of a conservative impurity from the atmosphere is used to analyze the intensity and size of chemical air pollution during the emission of hazardous substances from the landfill. A difference scheme of splitting is used to numerically solve the equation of convective-diffusive transfer of an impurity. The emission of hazardous substances from the landfill is modeled using the Dirac delta function. Findings. The developed mathematical model takes into account the main physical factors that affect the process of dispersion of hazardous substances from the landfill. On the basis of the developed numerical model, a computational experiment was conducted to assess the impact of the landfill on the environment. Originality. On the basis of the developed numerical model, a computer code was developed that allows predicting chemical pollution of the atmospheric wind and the underlying surface in the event of emission of hazardous substances from the surface of a solid waste landfill. The developed model and computer code make it possible to quickly assess the extent and intensity of environmental pollution from landfills, which is important when selecting sites for new or reconstructed landfills. 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 related to the impact of landfills on the environment. The results of the numerical experiment are presented.Item type:Item, 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.Item type:Item, Mathematical Modeling of Heat and Mass Transfer Processes in Safety Labour Problems : Dust and Heat Pollution(Prydniprovs’ka State Academy of Civil Engineering and Architecture, USUST, Dnipro, 2025) Biliaiev, Mykola M.; Berlov, Oleksandr V.; Kirichenko, Pavlo S.; Kozachyna, Vitalii A.; Tymoshenko, L. O.ENG: Problem statement. The operation of many industries is associated with dust and thermal air pollution. Particularly intense dust pollution of the air occurs during the operation of the mining complex. Intense thermal air pollution occurs during fires. Fires are a dangerous phenomenon at industrial and civil facilities. If a fire occurs at an industrial facility where oil storage facilities are located, a very intensive area of thermal pollution of the atmospheric air arises. This creates a risk of thermal injury to workers and a risk of ignition of oil storage facilities located near the source of ignition. An important practical task arises − reducing the risk of ignition of neighboring storage facilities. One of the means of reducing the risk of ignition is the use of protective screens, gabions at industrial sites. For practice, it is important to determine in advance the stability of such structures under the influence of a heat wave and to assess the "contribution" of these structures to reducing the air temperature near neighboring oil storage facilities. Reducing the air temperature near neighboring storage facilities increases the stability of bulk structures. Solving this class of problems requires the use of specialized mathematical models of aerodynamics and heat transfer. The purpose of the article. Creation of a CFD model for assessing thermal fields at an industrial site in the event of a fire and development of numerical models for predicting dust pollution of the air environment. Methodology. To simulate thermal fields at an industrial site, a potential flow and heat transfer model is used. To simulate the heating of a protective structure (shield), a one-dimensional heat conduction equation is used. Numerical integration of the modeling equations is carried out using explicit schemes. A mass transfer equation is used to model dust air pollution. Scientific novelty. Two numerical models are proposed for a comprehensive solution to the problem of determining the temperature field at an industrial site and inside a protective structure (screen) used to reduce the thermal load on a neighboring oil storage facility. Proposed numerical models for the analysis of dust air pollution. Practical significance. The implementation of the developed numerical models is implemented in real time. With the practical implementation of numerical models, almost all information regarding thermal fields formed on an industrial site during a fire can be obtained. This information allows you to identify areas with an intense increase in temperature, i.e. areas with a significant risk of injury to workers. Conclusions. Effective numerical models are proposed for solving complex problems in the event of a fire at an industrial site and in case of dust emission. The models make it possible to assess the level of thermal pollution of atmospheric air at the site and the effectiveness of using a protective screen to reduce the air temperature near a neighboring storage facility.Item type:Item, Mathematical Models for Water Treatment Problems(Український державний університет науки і технологій, Дніпро, 2025) Biliaiev, Mykola M.; Kozachyna, Vitalii A.; Kyrychenko, M. V.; Skuratov, M. O.; Chirkov, A. O.; Filonenko, H. K.ENG: 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.Item type:Item, 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.Item type:Item, 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.Item type:Item, Numerical Modeling of Groundwater Dynamics and Heat and Mass Transfer Processes(Pridneprovs’ka State Akademy of Civil Engineering and Architecture, USUST, Dnipro, Ukraine, 2024) Biliaiev, Mykola M.; Kozachyna, Vitalii A.; Kirichenko, Pavlo S.; Kozachyna, Valeriia V.; Kaidash, M. D.ENG: Problem statement. Groundwater is undergoing significant anthropogenic impact in many countries around the world. This impact results in changes in groundwater levels and deterioration of their quality. Protecting groundwater from anthropogenic impact involves solving several important tasks. A significant number of tasks are related to the need to predict the processes of filtration and heat and mass transfer in underground flows. In this regard, it is important to have specialized mathematical models as a modern scientific research tool. It should be noted that the use of physical experiments for problems of this class is significantly limited, due to the high cost of equipment, considerable time spent on setting up and conducting the experiment. The purpose of the article. Development of a set of numerical models for simulation of filtration and heat and mass transfer processes in groundwater. Methodology. To model the process of non-pressure flow of groundwater, the equation of non-pressure filtration is used. The two-dimensional equation of convective-diffusive movement of a pollutant is used to model the process of mass transfer of an impurity in groundwater. To model the process of heat transfer in groundwater, in the problem of groundwater freezing, a two-dimensional energy equation is used. For numerical integration of modeling equations, finite-difference schemes are used. Scientific novelty. Numerical models of filtration and heat and mass transfer processes have been developed that allow real-time analysis of changes in groundwater quality and thermal regime. Practical significance. The developed numerical models make it possible to quickly analyze non-stationary processes of heat and mass transfer in groundwater when developing drainage systems in flooded areas. Conclusions. Numerical models of filtration and heat and mass transfer in groundwater have been developed. For the practical use of the built models, standard hydrological information is required. The models make it possible to analyze the dynamics of ice formation in groundwater during the implementation of the technology of freezing groundwater flow.Item type:Item, 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.Item type:Item, 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 OlatoyeENG: 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.Item type:Item, 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.Item type:Item, 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.