Journal of Engineering Sciences / Журнал інженерних наук
Permanent URI for this collectionhttps://devessuir.sumdu.edu.ua/handle/123456789/34326
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Item Body movement along the surface of an inertial conveyor chute under combined friction(Sumy State University, 2025) Serilko, L.S.; Lyashuk, O.L.; Chasov, D.P.; Serilko, D.L.; Ihnatiuk, R.M.The main problem of inertial conveyors is the presence of friction between the load and the conveyor chute when the load moves in the needed direction. Transverse oscillations of the chute or other force factors are commonly used to reduce the force of friction when the body moves in the required direction. The article aims to develop a mathematical model for cargo movement in an inertial conveyor’s chute. In the proposed model, the walls with different friction coefficients were considered. The action of harmonic vibrations directed at a certain angle to the axis of the conveyor chute was also considered. The results obtained were verified experimentally. Theoretical studies were conducted using the fundamental laws of theoretical mechanics. Experimental studies were performed on a prototype of an inertial conveyor. The inclination angle for the axis of the conveyor chute to the direction of oscillations and the average transportation speed were evaluated depending on the friction coefficients between the chute walls and bottom, as well as the amplitude and frequency of oscillations. Theoretical and experimental studies help design inertial conveyors with improved technical characteristics.Item TOPSIS method for optimization of an apparatus for water and soil treatments(Sumy State University, 2025) Javanbakht, T.The article focuses on the design and application of a new apparatus for water and soil treatments and its optimization with the technique for order of preference by similarity to the ideal solution (TOPSIS). Achieving sustainability required developing experience with new devices, which improved the water and soil treatment outputs. Essential principles, including the irradiation process, treatment capability, and industrial development, were discussed. Water and soil treatments with new nanocomposites based on biocompatible and natural materials were also discussed. A well-implemented approach requires the consideration of creative design. The article addressed these issues by representing the apparatus characteristics of reliable decontamination of drinking water, wastewater, seawater, and soil. A user-centered design approach for apparatus development was also considered. The design for its industrial development was presented and discussed, emphasizing this approach’s commercial viability. The novelty of the proposed apparatus is in decreasing light reflection due to the oxygen uptake, which could be affected by water or soil extraction decontamination. The Fourier transform infrared spectroscopy showed the characteristic peak intensities of superparamagnetic iron oxide nanoparticles and silk fibroin nanoparticles. The predicted theoretical and experimental decrease in light reflection due to nanoparticle oxygen uptake was determined. Moreover, the analysis of the removal of water contaminants using the inductively coupled plasma mass spectrometry analysis showed a concentration decrease of 48 % for Cd and 50 % for Zn after water treatment with nanoparticles. The optimization results using the TOPSIS method showed that the choice of parameters corresponding to the designed apparatus (contaminants separation due to water treatment and experiment duration) and their weights could impact the candidates’ ranks. Moreover, the ranking could be changed due to improved water and soil treatment procedures. The designed apparatus based on the presented optimization can improve water and soil treatments and further applications in environmental science.Item Model of parametric reliability of woodworking machine tools(Sumy State University, 2025) Dziuba, L.F.; Pylypchuk, M.I.; Chmyr, O.Y.; Pavliuk, R.V.The article aims to develop a model of the parametric reliability of woodworking machine tools based on the criterion of technological accuracy. For this purpose, a mathematical model of the operating time of a woodworking machine to parametric failure was created using a scheme for changing the size of the workpiece. A linear differential equation characterizing the change in the dimensions for the machined workpiece was obtained based on the assumption of a linear relationship between the wear rate of the machine tool components and its technological accuracy. The differential equation was solved analytically using a Bernoulli approach. As a result, an analytical dependence was obtained for changing the workpiece dimensions. This dependence characterizes the technological accuracy of the machine tool during the overhaul period. The operating time intervals for woodworking machines between parametric failures were also evaluated. The probabilities of failure-free operation were calculated by considering the alpha probability density function for operating time intervals to failure of woodworking machine tools. Finally, it was found that the probability of failure-free operation of machine tools significantly depends on the time-depending parameter, which characterizes the relative durability of the machine tool.Item Energy conversion in the working nozzle of a pneumatic abrasive-jet unit(Sumy State University, 2025) Бага, Вадим Миколайович; Baha, Vadym Mykolaiovych; Pitel, J.The article investigates the working processes in the channels with relatively simple geometry, such as working nozzles and seals designed to regulate the working flow jet passing through them. The main aim was to solve an essential scientific and technological problem of improving flow part nozzle performance in the pneumoabrasive units by applying the results of the study of energy conversion mechanism, namely, the conversion of compressed air potential energy into kinetic energy of the nozzle outlet jet. Hydrodynamic methods of flow part profiling, CFD modeling, and a physical experiment were applied. The methods for rational choice of the working nozzle geometry and its operating mode were also carried out. The designs of working nozzles for hydro-pneumatic units, their systems, and elements were developed and improved. The air nozzle geometry was adapted to operate in the pneumo-abrasive unit, with the air abrasive mixture being its medium. River sand, with a grain size of about 0.5 mm, was used as an abrasive material. The numerical studies of the air-abrasive mixture flow in the nozzle flow part resulted in gaining detailed information about all the elements of its structure in the flow and beyond it within a wide range of operating modes due to the application of the ANSYS software. As a result, a new approach to working nozzles profiling based on providing a proper air-abrasive mixture flow movement with a minimum hydraulic axial and circumferential resistance was developed. This made it possible to increase both the air-abrasive mixture flow rate from a nozzle and its consumption factor value. The impact patterns of nozzle geometry and operating modes on its flow structure and other indicators considered while designing and upgrading the flow parts of the jet-abrasive nozzles were found. Overall, a new design for a working nozzle with better energy performance was developed.Item Simulation modeling of the adaptive system for hydraulic drives of a stalk forage separator(Sumy State University, 2025) Veselovska, N.R.; Rutkevych, V.S.; Shargorodskiy, S.A.; Yaropud, V.M.; Kupchuk, I.M.The article aims to increase the accuracy of the block-portioned stem feed separator, reducing unproductive power losses and dynamic loads in the hydraulic drive of the separator by developing scientific fundamentals based on nonlinear mathematical models and adaptive hydraulic drive systems. The research uses simulation modeling to design an energy-efficient hydraulic drive for a stem feed separator from trench storage. The proposed approach allowed for avoiding significant capital investments to manufacture a prototype. A detailed description of the physical model was carried out. It allowed for checking the results’ reliability and evaluating the rational improvements. As a result, a new design and the corresponding technological scheme of a stem feed separator from trench storage were presented. An approach for simulating transient processes in the hydraulic drive of the separator was also proposed. The experimental design allowed for studying the hydraulic drive in a dynamic mode for different processing loads and various parameters of the adaptive liquid flow separator and the whole system. A close match was found between analytical studies and numerical simulation during the research. This allowed for the recommendation of the obtained dependencies to apply in developing hydraulic drives of stem separators. Moreover, the proposed adaptive hydraulic drive of the stem feed loader allowed for adaptive change in the operation of the cutting unit drive according to the feed. Overall, the possibility of reducing the drive power for the stem feed loader to 5–6 kW was confirmed when using a hydraulic drive system with a mechanism for adapting the working bodies to the operating conditions.Item Determination of the force acting on the gas turbine wing in the heat-and-power installations(Sumy State University, 2025) Shalamberidze, M.; Tskipurishvili, T.; Lobzhanidze, G.; Zivzivadze, L.A design scheme for measuring the short-term impulse force acting on the gas turbine wing using the induction method was developed. It was compared with the results measuring the same force using the thermal method. The results of the impulsive force measurement by induction and thermal methods were also compared. After considering the experimental conditions, the thermal method was chosen for experimental studies. It allowed experiments to be conducted with intervals to ensure temperatures of the same magnitude on the surface of the flue gas on the gas turbine wing. The proposed measurement scheme using the induction method was also applied to control and manage the optimal conditions of the gas turbine power-generating device. As a result, a theoretical relationship was obtained as a mathematical relationship between the signal received during the measurement by the induction method and the force to be measured. The conditions for determining the actual value of the force were developed. The error in determining the force acting on the gas turbine wing using the induction method did not exceed 3 %.Item Experimental study of mechanical and durability characteristics of bio-mineralized concrete: A microstructure analysis(Sumy State University, 2025) Porselvan, R.; Lakshmi, T.S.; Tholkapiyan, M.Concrete primarily composed of cement is essential for construction but contributes to significant natural resource depletion and environmental concerns. To address this, substituting cement with pozzolanic materials (e.g., fly ash and micro silica) was explored to enhance sustainability while maintaining strength. However, challenges remain in optimizing the durability and self-healing capacity of concrete. This study aims to study the impact of bacterial concrete using Bacillus subtilis on strength and durability properties. The main focus of bio-mineralization was to improve the mechanical performance and sustainability of building materials. Concrete specimens were subjected to curing for 7, 14, and 28 days. As a result, compressive strength, flexural strength, split tensile strength, and durability parameters (i.e., water permeability and chloride penetration) were evaluated. Microstructural analysis through energy dispersion spectra and field-emitting scanning electron microscopy provided insights into the calcite precipitation mechanism within the concrete pores, aiding in densification and strength enhancement. The results demonstrated that bacterial infusion significantly improved strength at all cell concentrations compared to control specimens. Moreover, the bacterial concrete exhibited enhanced self-healing properties, as observed through reduced permeability and chloride penetration. This study highlights the potential of bacterial concrete to enhance structural performance and environmental sustainability, offering a viable solution for both improving durability and reducing the carbon footprint of concrete construction.Item Substantiation of the operating parameters of walnut drying equipment(Sumy State University, 2024) Kaletnik, G.; Tsurkan, O.; Spirin, A.; Gudzenko, N.; Prysiazniuk, D.; Didyk, A.The most important operation in walnut processing technology is drying to achieve the required moisture content. It is the most energy-consuming, and therefore, of course, there is an attempt to increase the energy efficiency of this process. Recent research and publications have shown many ways and means to dry nuts. According to the authors’ developments, the most effective are convective dryers, which can intensify the process by vibrating the material layer, which increases the heat transfer ratio. To determine the rational parameters of the drying process, a mathematical model was developed in which the nut is represented by a complex geometric shape – a sphere in a sphere, where the kernel is the inner sphere, and the shell is the outer sphere. The presence of harmful internal heat sources modeled the process of moisture removal. An equation was obtained in the criterion form that allowed temperature determination at an arbitrary point of the inner sphere at an arbitrary time depending on specific initial and boundary conditions, as well as the operating parameters of the drying process. The obtained mathematical model made it possible to reliably simulate the process of drying walnuts in a convective-vibration dryer and control the change in material temperature to ensure the high quality of the final product.Item Peculiarities of implementing multifractal analysis of the milled surfaces microrelief(Sumy State University, 2024) Balytska, N.O.; Prylypko, O.I.; Hlembotska, L.Y.; Shadura, V.A.; Moskvin, P.P.Manufacturing parts with a specific surface microrelief, which often determines their functional properties, is essential in various industry sectors. The practicality of studying the state of surface microrelief after various mechanical processing methods is of critical importance. It is crucial to develop specific mathematical approaches for calculating the quantitative characteristics of surface relief, a matter of significant practical interest. This paper aims to identify, discuss, and generalize the main features of implementing multifractal analysis of flat surfaces of steel and aluminum alloy samples formed by face milling with different cutting modes. Multifractal analysis of micrographs of C35 steel and AA2024 aluminum alloy sample surfaces was conducted after dry milling with various cutting modes. The statistical analysis of the area and volumes of spatial microforms reveals a linear relationship between their volumes and the sizes of the elementary cells in the coarse-graining method. This finding provides substantial evidence of fractal symmetry among these surface parameters after forming a periodic spatial relief on the surface due to the cyclic action of the tool’s cutting edge. Recommendations were developed to minimize errors in calculating multifractal parameters based on milled samples’ surface area and volumes of reliefforming microforms. It was established that the analysis of multifractal parameters of the machined surface should consider the cutting process’s physical characteristics. The recommendations developed in this paper showed a strong correlation between Rényi numbers, disorder parameters, and the face milling modes of steel and aluminum alloy.Item Development of a self-cleaning mechanism for torque-flow pumps(Sumy State University, 2024) Кондусь, Владислав Юрійович; Kondus, Vladyslav Yuriiovych; Ciszak, O.; Zhukov, A.; Муштай, Максим Валерійович; Mushtai, Maksym Valeriiovych; Полковниченко, Вадим Валентинович; Polkovnychenko, Vadym Valentynovych; Кругляк, Андрій Андрійович; Kruhliak, Andrii AndriiovychThe design of reliable and durable pumping units is consistent with the achievement of a number of the United Nations’ sustainable development goals (SDG), in particular, “Clean water and proper sanitation” (SDG 6), “Affordable and clean energy” (SDG 7), and “Industry, innovation and infrastructure” (SDG 9). Notably, the use of torque-flow pumps is associated with the need to transport liquids of various types. Such an operating process can cause clogging of the flowing part of the pump (primarily the impeller) by pumping products, mainly wet wipes, solids, and inclusions. As a result of scientific research, an effective self-cleaning mechanism for the torque-flow pump was developed, which was the primary goal. The authors proved that the flow of actual fluid in the interblade channels of the impeller is characterized by an uneven distribution of absolute pressure and relative speed, which is a prerequisite for forming an uneven pulsating nature of motion (the key hypothesis of the study). To implement the proposed hypothesis, an impeller with uniform and non-uniform distribution of blades was developed, and the movement of actual fluid flow in their interblade channels was considered. As a result of the research, it was established that in the expanded interblade channels, there is a pulsation of the absolute (total) pressure value, which is more than 2 times higher than the indicator of an impeller with a uniform distribution of blades. This creates prerequisites for self-cleaning of the developed impeller of the torque-flow pump.