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3D Modeling of Biological Wastewater Treatment in Aeration Tank
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2020) Biliaiev, Mykola M.; Lemesh, Maksym V.; Gunko, Olena Y.; Zadoia, Viacheslav O.; Mashykhina, Polina B.; Yakubovska, Zinaida M.
ENG: Purpose. The main purpose of the article is to develop a 3D CFD model for modeling the process of biological wastewater treatment in an aeration tank. Methodology. For mathematical modeling of the process of biological wastewater treatment in the reactor, taking into account the flow hydrodynamics, geometric shape of the aeration tank, convective-diffusion transfer of the substrate and activated sludge, a 3D CFD model was built. The model is based on the three-dimensional equation of motion of an ideal liquid and the equation of mass conservation for the substrate, activated sludge. The field of sewage flow rate in the aeration tank is calculated based on the velocity potential equation. The process of biological transformation of the substrate is calculated on the basis of the Monod model. The splitting scheme was used for numerical integration of the equations of convective-diffusion transfer of activated sludge and substrate. The splitting is carried out in such a way to take into account the transfer of substrate (activated sludge) in only one direction at each step of splitting. The calculation of the unknown value of the substrate (activated sludge) concentration is carried out according to an explicit scheme. The Richardson method is used to numerically integrate the three-dimensional equation for the velocity potential, and the unknown value of the velocity potential is calculated by an explicit formula. Euler's method is used for numerical integration of equations describing the process of substrate transformation and change in activated sludge concentration (Monod model). Findings. The software implementation of the constructed 3D CFD model is carried out. A description of the structure of the developed software package is provided. The results of a computer experiment to study the process of wastewater treatment in an aeration tank with additional elements are presented. Originality. A new multifactor 3D CFD model has been developed, which allows quick assessing the efficiency of biological treatment in an aeration tank. Practical value. The constructed 3D CFD model can be used to analyze the efficiency of the aeration tank under different operating conditions at the stage of sketch design of wastewater treatment systems.
3D численная модель для оценки территориального риска при теракте
(Дніпропетровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2018) Беляев, Николай Николаевич; Калашников, Иван Владимирович; Клименко, Ирина Владимировна; Козачина, Виталий Анатольевич
RU: Цель. Работа предполагает разработку 3D численной модели для оценки территориального риска в случае теракта с использованием химического агента. Методика. Для описания процесса рассеивания в атмосфере химического агента, выброшенного в случае теракта, используется трехмерное уравнение массопереноса примеси в атмосферном воздухе. Уравнение учитывает поле скорости ветрового потока, атмосферную диффузию, интенсивность эмиссии химического агента, наличие зданий возле места выброса химически опасного вещества. Для численного интегрирования моделирующего уравнения используется конечноразностный метод. Особенностью разработанной численной модели является возможность оценки территориального риска в случае теракта при различных метеоусловиях и наличии зданий. Для расчета поля скорости ветрового потока в условиях застройки применяется трехмерное уравнение для потенциала скорости. Результаты. Разработанная численная модель и пакет программ могут быть использованы для оценки территориального риска как в случае терактов с применением химических агентов, так и в случае экстремальных ситуаций на химически опасных объектах и транспорте. Построенная численная модель может быть реализована на компьютерах малой и средней мощности, что позволяет широко использовать ее для решения задач рассматриваемого класса, при разработке плана ликвидации аварийной ситуации. Представлены результаты вычислительного эксперимента, позволяющие оценить возможности предложенного метода оценки территориального риска в случае теракта с использованием химического агента. Научная новизна. Предложена эффективная численная модель для оценки территориального риска в случае теракта с применением химически опасного вещества. Метод может быть использован для оценки территориального риска в условиях городской застройки, что позволяет получать адекватные данные о возможных зонах поражения. Метод основан на численном интегрировании фундаментального уравнения массопереноса, выражающего закон сохранения массы в жидкой среде. Практическая значимость. Предложенный метод оценки территориального риска в случае теракта с применением химического агента может быть использован для расчета зон поражения возле административных зданий, центров и других социально значимых объектов.
3D-розрахунок вертикального відстійника на базі CFD-моделі
(Вінницький національний технічний університет, 2012) Біляєв, Микола Миколайович; Нагорна, Олена Костянтинівна
UK: Розглянуто побудову чисельної моделі масопереносу у вертикальному відстійнику. Моделювання здійснено на основі тривимірного рівняння переносу домішки і моделі потенціального руху. Для чисельного інтегрування використано неявні різницеві схеми. Наведено результати обчислювального експерименту.
Analysis of Temperature Field in the Transport Compartment of the Launch Vehicle
(Kaunas University of Technology, Kaunas, 2022) Biliaiev, Mykola M.; Rusakova, Tetiana I.; Biliaieva, Viktoriia V.; Kozachyna, Vitalii A.; Berlov, Oleksandr V.; Semenenko, Pavlo
ENG: The development of satellite linkage systems is based on the satellite’s transportation in space. The transportation of a satellite into orbit is carried out by a launch vehicle. The satellite is located in the transport compartment inside the main fairing. At the stage of the pre-launch preparation, it is necessary to fulfill very strict environment conditions inside the main fairing. Namely, it is very important to predict temperature field in the transport compartment inside the main fairing during its forced ventilation at the stage of pre-launch preparation. To calculate the temperature field formed by the ventilation of the transport compartment and release of heat from different elements of the satellite, the energy equation was used. This equation took into account the intensity of heat release from different parts of satellite, air flow pattern over the satellite, heat transfer in the transport compartment. The non-uniform field of the air flow velocity in the transport compartment was calculated on the basis of the potential flow model. The finite difference schemes were used for numerical integration of modeling equations. The computer code has been developed that implements the proposed numerical model. The results of computational experiments to estimate the temperature regime in the main fairing of the launch vehicle for different satellites is presented.
Anti-Terror Engineering in the Case of Possible Terrorist Attacks with Chemical Agents
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2018) Biliaev, Nikolai N.; Berlov, Oleksandr V.; Kalashnikov, Ivan V.; Kozachyna, Vitalii A.
ENG: Purpose. This work aims to develop a method of local outdoor reduction of the concentration of a chemically hazardous substance, which entered the atmosphere through a cafe roof vent. It also involves the creation of a numerical model for calculating the chemical contamination zone that allows assessing the effectiveness of the screens used to minimize its level. Methodology. To solve this problem, we used the velocity potential equation that al-lowed to determine the air flow velocity field, and the equation of convective diffusion dispersion of a chemically hazardous agent in the atmospheric air emitted through the ventilation system in case of a terrorist attack. The simulation took into account the uneven velocity field of the wind flow, atmospheric diffusion, emission rate of a chemically hazardous agent. In the numerical integration of the velocity potential equation, we used the Liebmann method. For the numerical solution of the equation of convective diffusion dispersion of the impurity, an implicit alternate-triangular difference splitting scheme was used. Findings. The developed numerical model allowed assessing the effectiveness of building screens used to reduce the concentration of a hazardous substance and minimize the risk of toxic damage to people outdoor during an initiated emission of a chemical agent. The constructed numerical model can be implemented on computers of low and medium power, which allows it to be widely used for solving problems of the class under consideration when developing an anti-terror engineering strategy. Originality. An effective numerical model for calculating the outdoor chemical contamination zone during a possible terrorist attack using a chemical (biological) agent has been proposed. The model can also be applied to assess the effectiveness of some protective measures aimed at reducing the air pollution level during a terrorist attack. Practical value. The developed numerical model can be used to organize protective actions near social objects of a possible chemical attack by a terrorist.
Application of Local Exhaust Systems to Reduce Pollution Concentration Near the Road
(Silesian University of Technology, Katowice, Poland, 2020) Biliaiev, Mykola M.; Pshinko, Oleksandr M.; Rusakova, Tetiana I.; Biliaieva, Viktoriia V.; Sładkowski, Aleksander
EN: In this study, the methodological foundations of the technology for the local reduction of chemical pollution from vehicles were improved through the use of twolevel suction units and guide plates of various lengths installed on the nozzles of the suction devices. A program has been developed for the numerical calculation of the carbon monoxide concentration field for evaluating the efficiency of using two-level exhaust systems with different lengths of guide plates on the gas flow selection pipes. The solution of the equations of hydrodynamics and mass transfer is carried out on the basis of finite-difference methods. A number of physical and computational experiments have been carried out; it has been established that the concentration of carbon monoxide in the zone of two-level suctions location decreases by 46-68%.
Atmosphere Pollution Modeling in the Case of Accident During Rocket Propellant Transportation by Trains
(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Biliaiev, Mykola M.; Biliaieva, Viktoriia V.; Kozachyna, Vitalii A.; Berlov, Oleksandr V.; Gunko, Olena Yu.; Chernyatyeva, Kateryna
EN: Abstract. At present time, in Ukraine the intensive development of solid-propellant missiles takes place. These missiles are called «Grim», «Grim-2», etc. Transportation of rocket propellant very often is carried out by trains. In the case of accident during such transportation great amount of toxic chemicals may be emitted into atmosphere. It is very important to predict the atmosphere pollution level near railways transport corridors to obtain the realistic information about the size of possible zones of hitting. To forecast the atmosphere pollution in the case of rocket propellant burning in railway wagon numerical models have been developed. These models are developed to predict the atmosphere pollution in two scales. The first scale is the simulation of the atmosphere pollution near the railway tracks (so called “local scale”). The second scale is the simulation of the atmosphere pollution on the territory which is adjacent to the railway tracks («urban scale»). The forecast is based on the Lagrangian model of toxic chemical dispersion. The models allow also to predict acid rain formation in the case of solid propellant burning products dispersion into atmosphere. To solve the governing equations we used difference schemes of splitting. The results of numerical experiments are presented.
Atmosphere Protection in Case of Emergency During Transportation of Dangerous Cargo
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2016) Berlov, Oleksandr V.
EN: Purpose. The paper highlights the development of numerical models for prediction of atmospheric pollution in case of burning of the solid rocket propellant in a railway car, situated near the building on railway territory. These models can be used in predicting the effectiveness of neutralization upon the atmosphere protection for this type of accidents. Methodology. To solve this problem the numerical models based on the use of Navier-Stokes equations, to determine the velocity field of the wind flow near cars and buildings, and contaminants-transfer equations in the atmosphere were developed. For the numerical integration of pollutant transport equation was used implicit «change – triangle» difference scheme. When constructing a difference scheme physical and geometric cleavage of the transfer equation is carried out in four steps. Unknown value of pollutant concentration at each step of cleavage is determined by the explicit scheme – the method of «point-to-point computation». For the numerical integration of the Navier-Stokes equations are used implicit difference schemes. When carrying out computing experiment also takes into account: the velocity profile of wind flow; interaction between the building and the wind flow and flame jet of solid rocket propellant; the presence of a railroad car; inside which there is a source of pollution; instability of pollutant emissions. On the basis of constructed numerical models was performed the computer experiment for assessing the level of air pollution at dangerous cargo rail transportation in case of emergency at railway territory.The application calculations for the timely combustion products neutralization of solid rocket propellant were carried out. Findings. The numerical models that let promptly calculate air contamination in case of emergency during solid rocket propellant transportation, as well as calculate the rational parameters of pollutant neutralization process were developed by the researcher. These models can be used for routine calculations of various accident scenarios simulation. Originality. Numerical models were developed; they take into account significant factors, influencing the pollutant dispersion process in the atmosphere. On their base a pollutant neutralization method was offered in emergency situations on the railway transport. Practical value. Efficient numerical models, so called «diagnostic models» were considered for the rapid calculation of the air pollution level and air protection technology in emergency situations, in particular, in the case of railway transportation the solid rocket propellant.
Calculation of the Efficiency of the Horisontal Settler with Baffles
(Саратов, 2014) Biliaiev, Nikolay N.; Kozachyna, Vitalii A.; Polubinskaja, E. V.
EN: The main purpose of this paper is development of the effective CFD model which can be used for computation speed field of the flow in the horizontal settlers which takes into account the geometrical form of the settler.
Calculation of «Vulnerability» Zone in Case of Terrorist Attack with Chemical Agents
(Дніпропетровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2018) Biliaiev, Mykola M.; Berlov, Oleksandr V.; Kalashnikov, Ivan V.; Kozachyna, Vitalii A.
EN: Purpose. The work involves the development of a numerical model for calculating the «vulnerability» zone of a possible terrorist attack objective with the use of a chemical agent in a builtup environment. The «vulnerability» zone is a territory near the attack objective, where the emission of a chemical agent during the attack will lead to undesirable consequences. The emission of a chemical agent outside the «vulnerability» zone will not create a dangerous concentration near the attack objective. Methodology. To solve this problem, we use the equation for the velocity potential, on the basis of which we determine the wind stream velocity field, and the equation adjoint to the equation of mass transfer in the atmospheric air of the chemical agent emitted in the event of a terrorist attack. During simulation, we take into account the uneven wind stream velocity field, atmospheric diffusion and the rate of emission of a chemically hazardous substance. For the numerical integration of the velocity potential equation, we use the method of A. A. Samarsky. For numerical solution of the adjoint equation, we introduce new variables and use an implicit difference splitting scheme. The peculiarity of the developed numerical model is the possibility of operative estimation of the «vulnerability» zone near a possible attack objective. Findings. The developed numerical model and computer program can be used for scientifically grounded assessment of the «vulnerability» zone near significant facilities in the event of possible attacks with the use of chemical (biological) agents. The constructed numerical model can be implemented on computers of small and medium power, which allows it to be widely used to solve the problems of this class when developing the emergency response plan. The results of the computational experiment are presented, which allow us to evaluate the possibilities of the proposed numerical model. Originality. An effective numerical model is proposed for calculating the «vulnerability» zone near the facility, which may be the target of a terrorist attack with the use of a chemical agent. The model is based on the numerical integration of the velocity potential equation and the equation adjoint to the equation of mass transfer of a chemically dangerous substance in the atmosphere. Practical value. The developed model can be used to organize protective actions near the target facility of a possible chemical attack by terrorists.
CFD моделирование аэроионного режима в рабочих зонах в условиях искусcтвенной ионизации воздуха
(Днепропетровский национальный университет железнодорожного транспорта имени академика В. Лазаряна, Днипропетровск, 2016) Беляев, Николай Николаевич; Цыганкова, Светлана Григорьевна
RU: Цель. Работа предполагает создание CFD модели расчета аэроионного режима в помещениях и в рабочих зонах при искусственной ионизации воздуха путем установки ионизатора внутри помещения с учетом наиболее существенных физических факторов, оказывающих влияние на формирование концентрационного поля аэроионов. Методика. Предложенная CFD модель расчета аэроионного режима в рабочих зонах при искусственной ионизации воздуха путем установки ионизатора внутри помещения основана на применении уравнений аэродинамики, электростатики и массопереноса. Уравнение массопереноса учитывает взаимодействие ионов различной полярности друг с другом и с частицами пыли. Расчет скорости движения воздушных потоков в помещении осуществлялся на основе модели потенциального течения, для чего было использовано уравнение Лапласа для функции тока. Для расчета дрейфа заряженных частиц под действием электрического поля использовалось уравнение Пуассона для электрического потенциала. При моделировании учитывались: 1) влияние геометрических характеристик рабочей зоны; 2) местоположение отверстий приточно-вытяжной вентиляции; 3) расстановка мебели и оборудования; 4) режим воздухообмена в помещении; 5) наличие препятствий в процессе рассеивания аэроионов; 6) конкретное место эмиссии частиц пыли и ионов различной полярности и их взаимодействие в помещении и в рабочих зонах. Результаты. Разработанная CFD модель позволяет определить концентрацию отрицательных ионов в помещении и в зоне расположения органов дыхания человека. Распределение концентрации отрицательных аэроионов представлено в виде изолиний концентрационного поля. Научная новизна. Авторами создана 2D CFD модель для расчета аэроионного режима в рабочих зонах, предоставляющая возможность определять концентрационное поле аэроионов в заданном месте в помещении. Предложенная модель разработана с учетом: размещения мебели и оборудования в помещении; геометрических характеристик помещения; местоположения источников эмиссии пыли и ионов различной полярности; физических процессов, влияющих на формирование концентрационного поля аэроионов. Практическая значимость. Полученная 2D CFD модель для расчета аэроионного режима в рабочих зонах позволит рассчитывать концентрацию аэроионов в месте расположения дыхательных органов человека с учетом основных физических факторов, определяющих формирование концентрационных полей аэроионов. Это даст возможность рационально расположить ионизаторы в рабочих помещениях для создания комфортных условий работы персонала.
CFD модель для оценки территориального риска и уровня загрязнения воздушной среды при эмиссии химического агента
(Национальный горный университет, Днепр, 2018) Беляев, Николай Николаевич; Калашников, Иван Владимирович; Берлов, Александр Викторович
RU: Предложен метод расчета распространения опасных веществ в условиях застройки, который позволяет осуществлять оценку территориального риска. Численное моделирование осуществляется на базе модели аэродинамики и распространения примеси в атмосферном воздухе. Численная модель ориентирована на проведение экспресс расчетов. Приведено описание алгоритма решения задачи по оценке территориального риска при эмиссии химически опасного вещества при экстремальной ситуации на промышленном объекте. Представлены результаты вычислительного эксперимента.
Complex of Numerical Models for Computation of Air Ion Concentration in Premises
(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпропетровськ, 2016) Biliaiev, Mykola M.; Tsygankova, Svetlana G.
EN: Purpose. The article highlights the question about creation the complex numerical models in order to calculate the ions concentration fields in premises of various purpose and in work areas. Developed complex should take into account the main physical factors influencing the formation of the concentration field of ions, that is, aerodynamics of air jets in the room, presence of furniture, equipment, placement of ventilation holes, ventilation mode, location of ionization sources, transfer of ions under the electric field effect, other factors, determining the intensity and shape of the field of concentration of ions. In addition, complex of numerical models has to ensure conducting of the express calculation of the ions concentration in the premises, allowing quick sorting of possible variants and enabling «enlarged» evaluation of air ions concentration in the premises. Methodology. The complex numerical models to calculate air ion regime in the premises is developed. CFD numerical model is based on the use of aerodynamics, electrostatics and mass transfer equations, and takes into account the effect of air flows caused by the ventilation operation, diffusion, electric field effects, as well as the interaction of different polarities ions with each other and with the dust particles. The proposed balance model for computation of air ion regime indoors allows operative calculating the ions concentration field considering pulsed operation of the ionizer. Findings. The calculated data are received, on the basis of which one can estimate the ions concentration anywhere in the premises with artificial air ionization. An example of calculating the negative ions concentration on the basis of the CFD numerical model in the premises with reengineering transformations is given. On the basis of the developed balance model the air ions concentration in the room volume was calculated. Originality. Results of the air ion regime computation in premise, which is based on numerical 2D CFD model and balance model, are presented. Practical value. A numerical CFD model and balance model for the computation of air ion regime allow calculating the ions concentration in the premises in the conditions of artificial air ionization taking into account the main physical factors determining the formation of ions concentration fields.
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 Biological Wastewater Treatment Processes in Aerotanks With Plates
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2020) Biliaiev, Mykola M.; Lemesh, Maksym V.; Biliaieva, Viktoriia V.; Mashykhina, Polina B.; Yakubovska, Zinaida M.
EN: Purpose. Efficiency determination of the aeration tank at the stage of design or reconstruction of bioreactors in which biological wastewater treatment is carried out requires the use of special mathematical models and calculation methods. The main purpose of the article is to develop CFD models for evaluating the operation efficiency of aeration tanks. Methodology. A numerical model has been developed for the computer calculation of the biological wastewater treatment process in aerotanks, taking into account hydrodynamics. The model is based on two-level mass conservation equations for the substrate and activated sludge and the velocity potential equation. The process of biological transformation of the substrate is calculated based on the Monod model. For the numerical integration of the mass transfer equations of activated sludge and substrate, the alternating-triangular difference splitting scheme is used. In this case, the basic equations are divided into two equations of a more simplified form. For the numerical integration of the equations for the velocity potential, it is split into two one-dimensional equations. Further, each equation is solved according to explicit scheme. For the numerical integration of equations that describe the process of substrate transformation based on the Monod model, the Euler method is used. Findings. The software implementation of the constructed numerical model has been carried out. The results of a computational experiment on the study of the wastewater treatment process in an aeration tank with plates are presented. This leads to the conclusion that the quality control of wastewater treatment in aeration tanks is possible with the help of plates. Originality. A multivariate CFD model has been developed, which makes it possible to quickly assess the efficiency of the aeration tank. A feature of the model is the ability to evaluate the operation of the aeration tank, taking into account its geometric shape and location of additional plates in the construction. Practical value. The constructed numerical model can be used during calculations in the case of designing aeration tanks, or in determining the efficiency of wastewater treatment under new operating conditions.
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.
Computing Model for Simulation of the Pollution Dispersion Near the Road with Solid Barriers
(Silesian University of Technology, Gliwice, Poland, 2021) Biliaiev, Mykola M.; Pshinko, Oleksandr M.; Rusakova, Tetiana I.; Biliaieva, Viktoriia V.; Sładkowski, Aleksander
ENG: In this study, a numerical model is proposed for calculating pollution zones near the road, taking into account the geometry of the automobile transport, meteorological conditions, the location of the barriers and their height, and the chemical transformation of nitrogen oxides in the atmospheric air. The numerical solution is based on the integration of the mass transfer equations using the finite-difference method. To determine the components of the air flow velocity vector, a two-dimensional model of the potential flow is used, where the Laplace equation for the velocity potential is the modeling equation. Based on this numerical model, a software package has been developed that allows computational experiments and does not require large expenditures of computer time. Based on the results obtained, an assessment was made of the effectiveness of the use of barriers to reduce the level of air pollution near highways. It has been established that the use of barriers of different heights reduces the level of pollution behind the road by approximately 20-50%.
Constructing a Method for Assessing the Effectiveness of Using Protective Barriers Near Highways to Decrease the Level of Air Pollution
(ПП ТЕХНОЛОГІЧНИЙ ЦЕНТР, Харків, 2021) Biliaiev, Mykola M.; Kozachyna, Vitalii A.; Biliaieva, Viktoriia V.; Rusakova, Tetiana I.; Berlov, Oleksandr V.; Mala, Yuliia
ENG: Highways are an intensive source of environmental pollution. Atmospheric air is exposed to the fastest anthropogenic influence. Therefore, a particularly important task is to minimize the level of air pollution near the highway. An effective method for solving this problem is the use of protective barriers of various shapes installed near highways. At the stage of designing these protective structures, an important task arises to assess their effectiveness. Estimation of the effectiveness of protective barriers by the method of the physical experiment takes considerable time to set up and conduct an experiment, as well as analyze the results of hysical modeling. This method is not always convenient during design work. An alternative method is the method of mathematical modeling. For the designer, it is very important to have mathematical models that make it possible to quickly obtain a predictive result and take into consideration a set of important factors on which the effectiveness of the protective barrier depends. A method has been devised that makes it possible to assess the effectiveness of using protective barriers to reduce the level of air pollution near the highway. It was found that an increase in barrier height by 80 % leads to a 22 % decrease in the concentration of impurities behind the barrier. It was established that applying a barrier with a height of 1.5 m leads to a 26 % decrease in the concentration of impurities in buildings adjacent to the highway. A method has been devised to assess the effectiveness of using absorbent "TX Active" surfaces on the protective barrier located near the highway. This study's result revealed that the application of a barrier with one "TX Active" surface leads to a decrease in the concentration of NO behind the barrier by an average of 43 %. When using a barrier with two "TX Active" surfaces, a decrease in the NO concentration behind the barrier is 85 % on average.
Determination of Areas of Atmospheric Air Pollution by Sulfur Oxide Emissions from Mining and Metallurgical and Energy Generating Enterprises
(ДВНЗ "Національний гірничий університет", м. Дніпро, 2017) Biliaiev, Mykola M.; Rusakova, Tetiana I.; Kolesnik, Valerіy Ye.; Pavlichenko, Artem V.
EN: Purpose. Development of methods and software for determining levels and zones of atmospheric air pollution by emissions from mining and power generating companies that contain significant volumes of sulfur oxides. Methodology. The forecast of the level of atmospheric air pollution by sulfur-containing emissions from mining and power generating companies is based on a mathematical model for calculating the concentration of sulfur dioxide, which takes into account the processes of its oxidation, as well as the formation and evaporation of sulfuric acid in the atmosphere. The numerical method is based on the joint solution of the equations of convective-diffusion transport of pollutants that come directly from enterprises or are formed additionally due to chemical reactions in the atmosphere. The technique is implemented using implicit difference schemes. Findings. The developed methodology and software allow predicting the levels of atmospheric air pollution by large industrial enterprises taking into account chemical transformations of sulfur oxides in the environment. A number of numerical experiments have been carried out to estimate the levels and zones of atmospheric air pollution in the city of Dnipro with sulfur dioxide near industrial enterprises, taking into account various meteorological conditions. Originality. The regularities of atmospheric air pollution by sulfur-containing emissions from industrial enterprises are established on the basis of a joint solution of transport process equations as for impurities coming from sources of pollution and transformation as a result of chemical reactions in the atmosphere. Practical value. The developed forecast method and software allow determining the concentration of pollutants in the atmosphere and assessing the level of environmental hazard of large industrial enterprises. The obtained patterns of dispersion of sulfur oxides make it possible to predict pollution levels of environmental objects on the territory of industrial cities and to introduce air protection measures in a timely manner.
Determining Zones of Chemical Pollution in the Citiesand Assessment of Chronic Diseases Risks
(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Biliaev, Mykola M; Rusakova, Tetiana I.
EN: Purpose. The scientific paper is aimed at creating a methodology of chemical pollution zones in the territories of industrial cities and accounting the possibility of assessing the risks of chronic diseases. Methodology. The method of numerical calculation of nitrogen dioxide concentration in atmospheric air is based on the solution of three-dimensional impurity transfer equations, which directly comes from a permanently stationary source (industri-al enterprise) and a linearly distributed source (highway). The method takes into account the process of chemical transformation of impurities and photolysis in the atmosphere. The numerical model is based on the splitting of model equations and their solution using an implicit difference scheme. Findings. The created software allows con-ducting computational experiments to calculate the areas of atmospheric air pollution with nitrogen dioxide, taking into account the interaction of impurities coming from various types of pollution sources and meteorological para meters. On the basis of the obtained field of nitrogen dioxide concentration, an assessment of the change in the risk of chronic intoxication associated with atmospheric air pollution with nitrogen dioxide over 50 years was carried out. Originality. For the first time the regularities of changes in the level of atmospheric air pollution with nitrogen dioxide have been established with due regard to the mutual influence of emissions from the industrial enterprise and highway and their chemical transformation in the atmosphere. The risk of chronic intoxication has been calcu-lated and its changes have been analyzed with due regard to the interaction of emissions from the industrial enter-prise and highway, it leads up to 10% of risk increasing. Practical value. Authors developed a mathematical model and method of numerical calculation. Software created on their base allows obtaining quickly quantitative results necessary in developing the system for monitoring the man-made loaded regions of the city. The obtained patterns of impurities dispersion allow us to estimate the levels of pollution in urban areas of the city by emissions from in-dustrial enterprises and highways. Accounting of the mutual impact of emissions and the calculation of risks of in-toxication allows solving environmental problems arising in the development of transport strategy in cities.

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