Journal of Engineering Sciences / Журнал інженерних наук
Permanent URI for this collectionhttps://devessuir.sumdu.edu.ua/handle/123456789/34326
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Item Computational approach to geometric modeling of plow bodies(Sumy State University, 2024) Yablonskyi, P.; Rogovskii, I.; Sobczuk, H.; Virchenko, G.; Volokha, M.; Vorobiov, O.In this article, a detailed analysis of modern research and publications on the selected subject was carried out related to the computer-variant geometric modeling of the working surfaces of the plow blades. Based on this, a new method of proper design was proposed. The performed scientific investigations aimed to create a flexible, productive, and universal approach for the automated shaping of tillage tools. The accentuated effectiveness of geometric modeling was achieved using a developed special mathematical apparatus adapted for use in the environment of current computer information systems of an engineering profile. The implementation was based on such parametric lines as heterogeneous rational B-splines, which are acceptable in automated design systems. The specified geometric models were characterized by the coverage of a sufficiently large range of plow heads. The indicated means of forming could conveniently adapt to the changing conditions of designing tillage tools suggested by theoretical calculations and practical experiments. The given facts contributed to the multifaceted clarification of the specified information. They also ensured the appropriate integration and the possibility of determining the most rational options among the studied varieties of plow dumps. Simultaneously, the most common group of dumps with cylindrical and other plow working surfaces was considered. The significant role of geometric models for qualitative coordination and the effective combination of many other models (e.g., strength, manufacturing technology, and operation conditions) was emphasized. This was aimed at comprehensive optimization throughout their life cycle, in this case of plows. The proper solution to the presented problems contributed to a successful solution to the actual scientific and applied problem of improving the quality of machinery.Item Methodology for service life evaluation of screens welded structures(Sumy State University, 2024) Shkut, A.P.The methodology of research on welded assemblies for fastening vibrators is based on modern software products, in particular SolidWorks Simulation in combination with SolidWorks Motion and hot spot stress (HSS) technology. It has been determined that the research on welded assemblies using the SolidWorks Education Edition software package is expedient, considering the most unfavorable situation, when there is a lack of fusion of edges. The solid-state model displays a lack of fusion as a gap between the welded parts. The research on the stress-strain state of welded structures using the finite element method shows that when the computational mesh cell size is reduced, the stress increases significantly, indicating the model singularity and the need for further application of the HSS technology. Research has revealed that the maximum stresses occur in those points of the welds where the longitudinal middle rib is connected to the plate and pipe. It has been determined that the service life of welded joints will exceed 2·106 cycles. To assess the accuracy of calculating the dynamic forces arising during the screen operation, the modeling results using the SolidWorks Motion program are compared with those classical methods that use the Lagrange equation of the second kind. It turned out that the calculation error does not exceed 30 %.Item The influence of the design features of the submersible pump rotor on the vibration reliability(Sumy State University, 2024) Маківський, Олексій Сергійович; Makivskyi, Oleksii Serhiiovych; Кондусь, Владислав Юрійович; Kondus, Vladyslav Yuriiovych; Pitel, J.; Сотник, Микола Іванович; Sotnyk, Mykola Ivanovych; Андрусяк, Владислав Олегович; Andrusiak, Vladyslav Olehovych; Полковниченко, Вадим Валентинович; Polkovnychenko, Vadym Valentynovych; Муштай, Максим Валерійович; Mushtai, Maksym ValeriiovychPumping equipment consumes about 20 % of the electrical energy produced by humankind. A significant, even drastic, reduction in the weight and size indicators of pumping equipment leads to a decrease in the cost price and, therefore, competitiveness of such products in the market. Simultaneously, it makes it possible to use more valuable and high-quality construction materials and technologies that improve the reliability of equipment and its energy efficiency, which in turn is a clear step in solving many UN Sustainable Development Goals (SDGs). According to the research results, it was proved that by increasing the frequency of the drive, it is possible to reduce the mass and size indicators of the submersible pump for the needs of the critical infrastructure sector by reducing the number of stages. Mainly, the amplitudes of oscillations near the rotation frequency are 12–22 % and do not exceed 35 % of the gaps in the seals, as required by the available international standards to ensure the guaranteed vibration reliability of the pump. Overall, using a bearingless support design will significantly increase the reliability of the developed pump.Item The distribution pattern of machining errors on woodworking machine tools(Sumy State University, 2023) Pylypchuk, M.I.; Dziuba, L.F.; Mayevskyy, V.O.; Kopynets, Z.P.; Taras, V.I.The article aims to develop a methodology for calculating and predicting the distribution patterns of wood machining errors to assess the operating conditions of the machine tool according to the technological accuracy criterion. It was analytically proven and experimentally confirmed that Weibull’s law accurately describes the distribution pattern of machining errors on woodworking machines. Based on the results of experimental studies of the accuracy of machining on machines for lengthwise sawing and plano-milling of wood, it was found that the primary indicator of the Weibull distribution law is a shape parameter that takes values within 1.89–3.11. The computational algorithm was developed for statistical modeling of the pattern of the distribution of machining errors according to the Weibull distribution law. It allows for determining the main parameters of the error distribution law and evaluating the operating conditions for the machine tool according to the technological accuracy criterion. The statistical modeling results for the distribution pattern of machining errors are correlated with the experimental data with an accuracy of up to 5 %, which confirms the reliability of the obtained simulation results. The developed approach also minimizes the restoration cost for the machine’s operability.Item Cutting forces simulation for end milling(Sumy State University, 2023) Petrakov, Y.V.; Ohrimenko, O.A.; Sikailo, M.O.; Myhovych, A.V.The cutting force in end milling is the essential perturbation of the machining system that limits the productivity of the process. Therefore, forecasting the cutting force when assigning the processing mode and the geometry of the allowance layer to be cut is an urgent task that requires an operational tool for its solution. The method of calculating the cutting force is presented, based on a mechanistic approach, when the geometric ratios of the cutter blades’ positions on the sweep determine the thickness of the undeformed chip. The developed algorithm calculates the cutting force by double integration, first by the length of the cutting edge and then by the number of such edges. The algorithm also allows the simulating of the outrun of the mill on the cutting force and its components. The created application program visualizes the simulating process by oscillograms of the cutting force components for both up and down milling. Experimental studies, in general, proved the adequacy of the developed modeling method. The created program is a tool for operational forecasting of the cutting force during the technological preparation of the end milling process in production.Item Design and manufacturing of polymer composite materials using quality management methods(Sumy State University, 2023) Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Mitalova, Z.; Павленко, Іван Володимирович; Павленко, Иван Владимирович; Pavlenko, Ivan Volodymyrovych; Trojanowska, J.; Іванов, Віталій Олександрович; Иванов, Виталий Александрович; Ivanov, Vitalii Oleksandrovych; Руденко, Павло Володимирович; Руденко, Павел Владимирович; Rudenko, Pavlo VolodymyrovychMany factors influence the design and manufacturing of products from polymer composite materials. The expert assessment method was applied in the article for the corresponding analysis. A cause-and-effect diagram was built as a result of a preliminary analysis of the influence of factors on the primary indicator of product quality indicators (e.g., wear resistance). Based on the expert assessment results and quality function deployment analysis, the most critical factors affecting wear resistance were obtained: polymer brand, filler shape and size, technological parameters of mixing, pressing, sintering, and mechanical processing. Their impact was studied to establish quantitative dependencies. A stable value of the wear resistance of the product in the manufacturing process can be ensured by timely adjustment of the mixing, pressing, and sintering modes. As a result of the structural analysis of the process of developing materials with predetermined properties at the enterprise according to the IDEF0 methodology, the importance of assessing the risks associated with the process of multi-criteria optimization of their main quality indicators was confirmed.Item Innovations in a modern engineering enterprise in the context of Industry 4.0 strategy(Sumy State University, 2023) Hricova, R.; Madzinova, R.Innovations are an essential part of business management in modern society. In addition to large enterprises and research and development centers, small and medium-sized enterprises also hide great innovative potential. Moreover, it is precisely the innovations that lead businesses to permanent growth and prosperity. In addition, from the point of view of Industry 4.0, innovation must be considered as an essential part of the functioning of a modern enterprise, regardless of its size. The article compares statistical indicators that capture enterprises’ innovative activity or inactivity in the Slovak Republic. Enterprises that want to define themselves as innovative should have a suitably prepared and functioning environment, while internal and external conditions are essential. However, it turns out that Slovakian companies have not created suitable conditions for innovation, and in the long term, their interest in innovation is declining. At the same time, because of the industrial revolution, many professions are also changing, and the demands for specific knowledge are not only growing for the newly created ones, but they will also require an active approach to changes, i.e., innovations. Companies must introduce an innovative approach in the education process itself, and as it shows, it will not be possible without a systemic approach.Item Simulation of point defects formation in the fuel element of a nuclear power plant’s wave reactor(Sumy State University, 2023) Opyatyuk, V.V.; Kozlov, I.L.; Karchev, K.D.; Vistiak, S.V.; Kozlov, O.I.; Turmanidze, R.This paper considers the point defects that influence the operation of a wav nuclear power reactor with a uranium fuel medium. The formed individual point defects or such defect groups can produce a perturbing effect on the stability of the nuclear reactor operating mode and involve its transition to an unstable state. Studies have been carried out on the effect on the characteristics of the nuclear burnup wave in a medium with neutron multiplication for 2D geometry. For the calculation, the uranium-thorium fissile medium has been considered. The parametric calculations were carried out with 235 U different enrichment percents and different values of neutron activation energy. At that, it was assumed that the wave (flow) reactor stable operation region is located in the range of activation energies from 10–3 eV to 1 eV or in the region from 2 MeV to 8 MeV. When calculating the neutron flux intensity in a wave reactor, the influence of point defects and their aggregates on the decelerating elastically scattered neutrons’ flux density and the flux density of decelerating non-elastically scattered neutrons was considered. The dependences of the point defects formation rate on the medium fissile temperature for several compositions of the uranium-thorium medium are obtained. As visually identified, the graphic materials obtained during the calculations are similar to the photos of fuel rods after the energy campaign.Item Information-extreme machine learning of wrist prosthesis control system based on the sparse training matrix(Sumy State University, 2022) Супруненко, Микита Костянтинович; Супруненко, Никита Константинович; Suprunenko, Mykyta Kostiantynovych; Зборщик, Олександр Петрович; Зборщик, Александр Петрович; Zborshchyk, Oleksandr Petrovych; Sokolov, O.The article considers the problem of machine learning of a wrist prosthesis control system with a noninvasive biosignal reading system. The task is solved within the framework of information-extreme intelligent data analysis technology, which is based on maximizing the system’s information productivity in machine learning. The idea of information-extreme machine learning of the control system for recognition of electromyographic biosignals, as in artificial neural networks, consists in adapting the input information description to the maximum total probability of making correct classification decisions. However, unlike neuro-like structures, the proposed method was developed within a functional approach to modeling the cognitive processes of the natural intelligence of forming and making classification decisions. As a result, the proposed method acquires the properties of adaptability to the intersection of classes in the space of recognition features and flexibility when retraining the system due to the recognition class alphabet expansion. In addition, the decision rules constructed within the framework of the geometric approach are practically invariant to the multidimensionality of the space of recognition features. The difference between the developed method and the well-known methods of information-extreme machine learning is the use of a sparse training matrix, which allows for reducing the degree of intersection of recognition classes significantly. The optimization parameter of the input information description, the training dataset, is the quantization level of electromyographic biosignals. As an optimization criterion is considered the modified Kullback information measure. The proposed machine learning algorithm results are shown in the example of recognition of six finger movements and wrist.Item Rotor dynamics of turbocompressor based on the finite element analysis and parameter identification approach(Sumy State University, 2022) Вербовий, Антон Євгенович; Вербовой, Антон Евгеньевич; Verbovyi, Anton Yevhenovych; Хоменко, Владислав Володимирович; Хоменко, Владислав Владимирович; Khomenko, Vladyslav Volodymyrovych; Neamtu, C.; Pavlenko, V.; Симоновський, Віталій Іович; Симоновский, Виталий Иович; Symonovskyi, Vitalii Iovych; Павленко, Іван Володимирович; Павленко, Иван Владимирович; Pavlenko, Ivan VolodymyrovychThe article is devoted to improving methods for designing a finite element model of rotor dynamics. For this purpose, numerical implementation of the authors’ computer program “Critical frequencies of the rotor” was developed based on the computer algebra system MathCAD. As a result of the scientific work, a refined mathematical model of rotor dynamics using finite beam elements was created. This model considers the dependence of the radial stiffness characteristics of the bearing supports on the values of the critical frequencies. The reliability of the mathematical model was justified by the permissible differences of the obtained results within 2% compared with the results of finite element analysis using the ANSYS software. The theorem was also proven by the mutual location of the spectra of the natural and critical frequencies. Overall, the proposed scientific approach reduces preparation and machine time compared to numerical modeling using the ANSYS software without losing the accuracy of the calculations.