Browsing by Author "Kirichenko, Pavlo S."

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Computer Modeling of Air Pollution in Case of Dust Cloud Movement in Open Pit Mine
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Biliaieva, Viktoriia V.; Kirichenko, Pavlo S.; Berlov, Oleksandr V.; Gabrіnets, Volodymyr O.; Horiachkin, Vadym M.
ENG: Purpose. Explosions in open pits lead to the formation of dust clouds. These clouds lead to intense air pollution. An important task is the development of methods for predicting the dynamics of atmospheric air pollution during ex-plosions in open pits. The purpose of this work is development of a numerical model to predict atmosphere pollution after explosion in open mine pit. The task is to develop a numerical model that would allow for the calculation to take into account the geometrical shape of the open pit mine, the parameters of the meteorological situation (wind speed, atmosphere), the shape of the dust cloud that is formed in the open pit mine at the site of the explosion. Methodology. Mathematical modeling of dust cloud dispersion during an explosion in an open pit mine is based on the use of fundamental equations of aerodynamics and mass transfer. The airflow velocity field in the open pit mine is modeled using the Laplace equation for the velocity potential. The formation of the concentration field of dust is mod-eled on the basis of the equation of convective-diffusion dispersion of an impurity. For numerical integration of model-ing equations, difference schemes are used. The Laplace equation for the velocity potential is numerically integrated using the Richardson method. For the numerical integration of the convective-diffusion dispersion equation for an im-purity, an implicit difference splitting scheme is used. Findings. A CFD model has been developed that allows you to calculate the formation of pollution zones during the movement of a dust cloud in the open pit mine. A feature of the developed model is the speed of calculation. For practical use of the developed model, standard input information is required. Originality. In contrast to the existing models in Ukraine, the developed numerical model allows taking into account the geometrical shape of the open pit mine and the geometrical shape of the dust cloud when making predictive calculations to assess the level of air pollution caused by explosions in open pits. Practical value. The developed nu-merical model can be implemented on computers of low and medium power. For practical use of the numerical model, standard information on meteorological conditions in open pit mine is required. The numerical model can be used for environmental assessment of the effect of explosions in open pit mine on environmental pollution and work areas.
Computer Simulation of Dead-End Mine Working Ventilation
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Biliaieva, Viktoriia V.; Kirichenko, Pavlo S.; Gunko, Olena Y.; Bondarenko, Iryna O.; Mashykhina, Polina B.; Yakubovska, Zinaida M.
ENG: Purpose. The important problem in the field of ecological safety and industrial safety is providing of normal microclimate in dead-end mine working. In these regions of the mine methane gas can be accumulated and as a result explosion may take place. So, to avoid these accidents it is important to ventilate appropriately dead-end mine working. The purpose of the work is development of quick computing mathematical model to obtain information about dead-end mine working ventilation process. Methodology. The process of dead-end mine working ventilation computing is separated in two stages. At the first stage the velocity flow field is computed in the dead-end mine working. We consider the situation when the suction tube is situated in this region. To solve this problem the fluid dynamics model of inviscid gas flow was used. At the second stage of the computational modeling the convective-diffusive equation of admixture transfer was used. The equation takes into account non-uniform flow field in the dead end mine workings. Findings. The developed numerical model was coded using FORTRAN language. The developed computer code allows to perform numerical experiment to assess the efficiency of suction tube imple-mentation to decrease methane gas concentration in dead-end mine working. Originality. The developed numerical model takes into account physical factors, which are not considered nowadays in the empirical models, which are used for solving the problems of dead-end mine working ventilation. It allows taking into account the geometrical form of the dead-end mine working. Practical value. The developed computer program allows to perform calculations to assess the efficiency of suction system used for the ventilation of the dead-end mine working.
Construction of a Mathematical Model for Dust Transport Process at an Industrial Site with a Perforated Protective Screen
(TECHNOLOGY CENTER PC, Kharkiv, 2026) Biliaiev, Mykola M.; Berlov, Oleksandr V.; Biliaieva, Viktoriia V.; Kirichenko, Pavlo S.; Kozachyna, Vitalii A.; Mashykhina, Polina B.; Savin, Valerii V.; Semenenko, Pavlo V.; Usenko, Andrii Yu.; Foris, Svitlana M.
ENG: This work considers the process of dust pollution of the air at an industrial site when using a protective perforated screen. The removal of dust from contaminated land surfaces in areas where there are coal storage facilities leads to intensive air pollution in working areas. This poses a threat to the health of workers. Therefore, for practice, an important solution is to reduce the level of dust pollution of the air at industrial sites. A likely engineering solution to such a task is to use protective screens, in particular, protective screens with perforations. These screens reduce the speed of the oncoming wind flow, which, in turn, reduces the intensity of dust formation. The location of the screens at an industrial site is important. A laboratory experiment was conducted to determine the patterns of air flow velocity distribution behind a protective screen with perforations. The experimental data showed that the screen makes it possible to reduce the wind flow velocity by 5–6 times over an extension of the order of 2H from the screen (H is the height of the screen). The air flow velocity increases intensively behind the screen in the area 2H–4H. These results make it possible to determine the rational location of the screen relative to the dust formation area. For theoretical assessment of the effectiveness of these screens, a numerical model was built based on the fundamental equations of continuum mechanics. The modeling equations include the dust mass transfer equation and the potential motion equation. Using the constructed numerical model, a computational experiment was conducted, which confirmed the effectiveness of using perforated protective screens: the area of dust air pollution in height decreased almost 3 times. The cost of computer time for conducting a computational experiment is 2 seconds. This makes it possible, when carrying out design work, to perform a series of calculations in a short period of time.
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.
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.
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.
Mathematical Modeling of Shock Wave Interaction with Wagon
(IOP Publishing, 2020) Khrutch, V. K.; Biliaiev, Mykola M.; Kozachyna, Vitalii A.; Berlov, Oleksandr V.; Kirichenko, Pavlo S.; Biliaieva, Viktoriia V.
EN: In case of some accidents on railways there may be situations when the shock wave appears and interacts with different objects on the railway (wagons, cargo, buildings etc.). In these cases it is necessary to predict the possible effect of shock wave diffraction on the different objects. Study of these problems on the basis of physical experiments (laboratory experiment or field experiment) demand expensive and unique experimental facility. In some cases physical experiment can’t be set. That is why mathematical simulation plays the important role in solving problem connected with shock wave propagation. For practice it is necessary to have predictive quick computing mathematical models which allow to perform numerical experiment on the basis of non-powerful computers. Now, in Ukraine, there is a real deficit of mathematical models which allow to compute quickly shock wave interaction with different objects. The aim of this work was development of quick computing numerical model to simulate shock wave propagation and its interaction with the wagons. The model is based on the numerical integration of Euler equations which are written in integral form. To solve modeling equations difference scheme of splitting was used. Results of numerical modeling are presented.
Modeling Coal Dust Dispersion from Pile with Protection Barriers
(EDP Sciences, 2020) Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Berlov, Oleksandr V.; Kozachyna, Vitalii A.; Kirichenko, Pavlo S.; Oladipo, Mutiu Olatoye; Poltoratskа, Viktoriia
EN: Abstract. The results of laboratory studies to evaluate the effectiveness of barriers which are used to reduce dust pollution from the coal pile are presented. The use of the Г-shaped barrier, which is set differently near the coal pile model, has been studied. A numerical model is proposed to compute coal dust concentration in the air near the pile. The Navier–Stokes equations are used to model the wind flow over the coal pile. These equations are written in the variables "vorticity-stream function". To simulate the process of coal dust dispersion from the coal pile, the equation of convective-diffusion transfer of the passive impurity is used. For numerical integration of the modeling equations, difference schemes of splitting are used. Developed numerical model allows to perform numerical experiments taking into account the complex geometric shape of the pile and screens. The results of the computational experiments are presented.
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.
Numerical Simulation of the Black Sea Pollution for the Case of the Mine Waters Dischargev
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2011) Biliaiev, Mykola M.; Kirichenko, Pavlo S.
EN: The 3D numerical model was developed and used to simulate the sea pollution after mine waters discharge. The model is based on the numerical integration of the K-gradient transport model and the model of potential flow. The results of numerical experiment are presented.
Quick Computing Numerical Model of Pollutant Dispersion in Urban Street Canyon
(Kaunas University of Technology, Kaunas, 2022) Biliaiev, Mykola M.; Rusakova, Tetiana I.; Biliaieva, Viktoriia V.; Berlov, Oleksandr V.; Kozachyna, Vitalii A.; Kirichenko, Pavlo S.
ENG: This research proposes a numerical model for the quick calculation of air pollution by emissions from cars in urban area such as "canyon". The Euler equations written in Helmholds variables were used to calculate the wind flow velocity field in street canyon. A special technique is used to calculate the vorticity in the corner points of buildings and barriers near the road. To calculate pollutant concentration field in the street canyon, which is formed from the traffic flow, the mass transfer equation was used, which took into account pollutant emission rate from cars, atmospheric diffusion, gravitational deposition, convective transfer. For numerical integration of modeling equations change-triangular finite-difference schemes were used The computer code realizing the developed numerical model was developed. The results of computational experiments to estimate the level of air pollution for different variants of the "canyon" scheme are presented.
Reducing of Coal Dust Release from Train Wagon with Barrier
(IOP Publishing, 2020) Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Kozachyna, Vitalii A.; Berlov, Oleksandr V.; Oladipo, Mutiu Olatoye; Kirichenko, Pavlo S.
EN: Intensive environment pollution takes place during coal transportation in open wagons. Emission of coal dust from the coal wagons cause contamination of atmosphere and territory adjacent to the railway track. Different ways to reduce coal dust emission from the wagon are used in the world. Unfortunately, in Ukraine, this problem is far from solution and there is no serious research work in this field. The aim of this work was laboratory study of coal dust emission from the wagon model which had different barriers installed on the wagon. Laboratory experiments were carried for coal wagon without barrier and for coal wagon which had barriers of two types. Barrier of the first type had downwind wing. Barrier of the second type had upwind wing. The contamination zones, concentration near the model were studied. The obtained results illustrate that installation of barriers influence intensity of transport corridor contamination. Also a numerical model was developed to estimate wind flow and coal dust dispersion from the coal wagon. Equation of potential flow and equation of coal dust dispersion were used. Implicit difference schemes of splitting were used for numerical simulation of governing equations. Results of numerical experiment, which were performed, are presented.