67 research outputs found
RETRACTED: Forecasting the development dynamics of coastal systems utilizing remote sensing data
Get PDFSee the retraction notice E3S Web of Conferences 549, 00001 (2024), https://doi.org/10.1051/e3sconf/20245490000
Field data filtering for the digital simulation of three-dimensional turbulent flows using the LES approach
No full textСухинов Александр Иванович – член-корреспондент РАН, доктор физико-математических наук, профессор, заведующий кафедрой математики и информатики, Донской государственный технический университет, e-mail: [email protected].
Проценко Софья Владимировна – кандидат физико-математических наук, доцент кафедры математики, Таганрогский институт имени А.П. Чехова (филиал) Ростовского государственного экономического университета (РИНХ), e-mail: [email protected].
Проценко Елена Анатольевна – кандидат физико-математических наук, доцент кафедры математики, Таганрогский институт имени А.П. Чехова (филиал) Ростовского государственного экономического университета (РИНХ), e-mail: [email protected]. Sukhinov Aleksandr Ivanovich is Corresponding Member of the Russian Academy of Sciences, Doctor of Physical and Mathematical Sciences, Professor, Head of the Mathematics and Computer Sci-ence Department, Don State Technical University, Rostov-on-Don, Russian Federation, e-mail: [email protected], ORCID iD: https://orcid.org/0000-0002-5875-1523
Protsenko Sofya Vladimirovna is Candidate of Physical and Mathematical Sciences, Associate Professor of the Mathematics Department, Chekhov Taganrog Institute (branch) Rostov State University of Economics, Taganrog, Russian Federation, e-mail: [email protected], ORCID iD: https://orcid.org/0000-0001-9656-8466X
Protsenko Elena Anatol'evna is Candidate of Physical and Mathematical Sciences, Associate Professor of the Mathematics Department, Chekhov Taganrog Institute (branch) Rostov State University of Economics, Taganrog, Russian Federation, e-mail: [email protected], ORCID iD: https://orcid.org/0000-0001-7911-3558XТурбулентность и последующее перемешивание являются важными механизмами, определяющими динамику прибрежной зоны, перенос импульса, массы и тепла. В работе мелкомасштабное движение исключается из уравнений Навье-Стокса при помощи применения операции фильтрации и моделируется с использованием подсеточных моделей. Для этого в двумерном и трехмерном случаях применены различные виды фильтров: коробочный фильтр, фильтр Гаусса и фильтр Фурье, с постепенным уменьшением ширины фильтра, что позволяет воспроизвести более широкий частотный диапазон флуктуаций решения. Процедуре фильтрации подвержены натурные данные, полученные в ходе экспедиции в Центрально-Восточной части Азовского моря и в Таганрогском заливе на НИС «Денеб» Южного научного центра РАН. Для измерения трехмерного вектора скорости движения водной среды использовался гидрофизический ADCP-зонд Workhorse Sentinel 600, с помощью которого получено более 3 000 000 исходных измерений, в каждой точке (на каждой станции, которых 17) – более 150 000. Полученные данные планируется использовать для численного моделирования трехмерных турбулентных течений с применением подхода LES и сопоставления с результатами осреднения по RANS. В статье рассмотрены возможности применения различных типов аппроксимаций для параметризации вертикального турбулентного обмена. Проведено сравнение алгебраических моделей расчета коэффициента вертикального турбулентного обмена и полуэмпирических моделей турбулентности. Turbulence and subsequent mixing are important mechanisms which determine the dy-namics of the coastal zone, as well as the transfer of momentum, mass and heat. In this paper, small-scale motion is excluded from the Navier–Stokes equations by applying the filtering operation. It is then modeled using subgrid models. In two-dimensional and three-dimensional cases, various types of filters are used: a box filter, a Gaussian filter and a Fourier filter, with a gradual decrease in the filter width. This enables the reproduction of a wider frequency range of fluctuations of the solution. The natural data obtained during the expedition in the Central-Eastern part of the Sea of Azov and in the Taganrog Bay at the research vessel Deneb of the Southern Scientific Center of the Russian Academy of Sciences were subjected to the filtration procedure. The hydrophysical ADCP probe Workhorse Sentinel 600 was used to measure the three-dimensional velocity vector of the water medium. In this way more than 3,000,000 initial measurements were obtained, at each of the 17 stations more than 150,000 were taken. The data thus obtained will be used for the digital simulation of three-dimensional turbulent flows using the LES approach and comparison with the results of averaging by RANS.Исследование выполнено за счет гранта Российского научного фонда № 22-71-00015, https://rscf.ru/project/22-71-00015/
The peculiarities of aperture field distribution of reflector antenna with arbitrary positioned irradiator
No full textImproved parametrization of the vertical turbulent exchange coefficient, taking into account the shallow water bodies specifics
No full textThe article is devoted to the problem of improving the parameterization of the coefficient of turbulent exchange in shallow water bodies with significant depth differences and intensive vertical mixing. The article presents the basic equations of the model of taking into account the wave effect on the inhomogeneous vertical coefficient of turbulent exchange. This model is integrated into the system of Navier-Stokes equations taking into account the variable density, temperature and salinity, which describes the movement of a liquid under the influence of various forces, including pressure and viscosity, as well as forces caused by the action of waves. The article presents the discretization of the Navier-Stokes equations and the transfer equations by the finite difference method in three measurement directions. The additional term describing the wave effect on the vertical velocity in a shallow-water reservoir depends on the characteristics of the wave field: amplitude, angular frequency, wave number and coordinates. Using a model that takes into account the wave effect in three measuring directions and inhomogeneous turbulent exchange in the vertical direction, detailed information about the dynamics of waves in the simulated section of a shallow reservoir was obtained. The forecast of changes in hydrodynamic wave processes of the coastal zone is constructed. Inhomogeneous vertical turbulent exchange can vary significantly in different parts of a shallow reservoir and affect wave activity. Taking into account these changes makes the model more accurate and relevant to real conditions
Procedure of Computation of Local Phase Center Position and Analysis of Its Displacement for Antennas with Elliptical Polarization Radiation
No full textDynamically changing bottom relief modeling based on spatially inhomogeneous 3D mathematical model of wave hydrodynamics
No full textThe article is devoted to the construction and adaptation to natural and climatic conditions and geographical features of precision mathematical models of hydrodynamics of wave processes and relief formation. The incompleteness of data is characteristic of the new tasks considered in the article, the solution of this problem is carried out by involving remote sensing and cadastral survey data. It is essential to include in this complex algorithm for constructing raster models of dynamically changing bottom relief based on known cadastral survey data and remote sensing data. The software package described in this paper makes it possible to reduce the forecast time of hydrophysics processes, including dangerous and catastrophic phenomena. On the basis of the developed software package, prognostic calculations of the processes of coastal erosion and changes in the bottom relief were performed. Modeling of the state of a water body takes into account the characteristic features of natural processes, among which it is worth noting the spatial and temporal variability of relief formation
Methodological aspects of providing resources for creation of economic security at companies
No full textThe purpose of the research is in the coverage of content and specific costs for long-term economic security, as well as the justification criteria of accessing these costs in different stages of the life cycle of industrial enterprises. The article shows the objective need to create conditions for sustained development and economic security of domestic production, which is possible only by deliberate, conscious actions of long-term and program character. The major object of expenses enhance the economic security of enterprises is considered the technical, technological, organizational, economic and financial system at the stages of creation, maintenance and improvement. The author works out the criteria for accessing costs to ensure the economic security of industrial enterprises at different stages of their life cycle. The article shows the basic forms of loss of economic security of companies and its reproducing at the expense of the reserves established. It is shown that investments into the creation of reserves should be performed during the creation of the enterprise itself, and operating costs are made directly during operation. The author offers the technique of economic security index as the value of operating costs reserves of the company
Innovative activity – basis for economic security of enterprise
No full textThe aim of the research is to highlight the contents and specifics of innovation processes management mechanism on enterprises and to substantiate the scheduled management system of innovation process and to develop the complex system of innovation management.
The objective necessity of innovative ensuring of industrial enterprises stable functioning is shown, the author’s innovation numerical score which is based on the level of novelty and difficulty of the solved task is given. The classification of innovation by types: technical, technological, organizational, managerial, economic, social is proposed by author. The system of indicators, which characterize the industrial enterprises innovation activity level is developed. The system includes: total quantity of innovations applied, scores of use, comparative indicator of application intensity, innovations importance, productivity increase due to innovations, material resources use decrease due to innovations, production casts decrease, innovation products volume in total production. The essence of the developed by author scheduled management system of innovation process on machine – building enterprise on the base of network matrix is revealed.
This will allow to apply more rational model of investment-innovative development of the enterprise management on industrial enterprises
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