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Über dieses Buch

This book reports on topics at the interface between manufacturing, mechanical and chemical engineering. It gives a special emphasis to CAD/CAE systems, information management systems, advanced numerical simulation methods and computational modeling techniques, and their use in product design, industrial process optimization and in the study of the properties of solids, structures and fluids. Control theory, ICT for engineering education as well as ecological design and food technologies are also among the topics discussed in the book. Based on the International Conference on Design, Simulation, Manufacturing: The Innovation Exchange (DSMIE-2018), held on June 12-15, 2018, in Sumy, Ukraine, the book provides academics and professionals with a timely overview and extensive information on trends and technologies behind current and future developments of Industry 4.0, innovative design and renewable energy generation.

Inhaltsverzeichnis

Frontmatter

Manufacturing and Materials Engineering

Frontmatter

Implementation of CALS-Technologies in Quality Management of Product Life Cycle Processes

The aspects of the usage of CALS-technologies in support of the life cycle of products are considered in this research. The identification of problems and the main ways of creating a unified information space in the quality management system are focused on, due to the principles of ISO standards series 9000. Based on the analysis, a unified methodological approach to the construction of quality management systems for the application of CALS-technologies is introduced. As an example, a conceptual model of the information system for lifecycle management of instrumental production based on the process approach was suggested. The algorithm of construction and implementation of the introduced model with the consideration on the features of this system is developed. It is shown that observance of the recommendations set forth in the research work will allow to improve the quality of technological equipment as well as to facilitate the optimization of its processes, then it will lead to an increase in labor productivity, reducing resource dependence and costs.

Yuliia Denysenko, Oksana Dynnyk, Tetiana Yashyna, Nina Malovana, Viliam Zaloga

Variation Coefficient and Some Distribution Laws in the Context of Cutting Tools and Other Technical Objects Reliability Modeling

In the paper some practice of the usage of three distribution laws: Gauss, Gamma, and Weibull for reliability modeling of technical objects in general and metal cutting tools in particular are analyzed and arranged. Selection of distribution law and estimation of its parameters based on empirical data are the main tasks in reliability simulation. It is stressed that selection of the above-mentioned laws should be made taking into account the process mechanism; otherwise, it leads to some false conclusions such as equivalence of Gamma and Weibull distribution. Mentioned distribution laws and their usage are analyzed from the position of physical interpretation. The conditions are shown when the above-mentioned distribution laws are similar. The simplified dependence that connects the shape parameter of Weibull distribution and variation coefficient is obtained and confirmed statistically. The variation coefficient defines the shape parameters for both Gamma and Weibull distributions uniquely and reflects the mechanism of the process. The variation coefficient and failure rate in addition to formal criteria are shown to be the main indicators for the distribution law selection.

Mykhaylo Frolov

Measurement of Non-rigid Tools Action Force During Finishing

The purpose of the research was to design a device (dynamometer) for measuring the action force on work surface (cutting force) during the finishing process with non-rigid tools such as flap wheels, mechanical brushes with metal and nonmetal fibers, or using jet processing with various fillings – sand, grinding materials, metal shot, glass microbeads, etc. The information about force level is used, for example, to select a tool or a method for finishing of thin-walled parts or edges as well as for determination of rational processing modes of the method selected. This device considers special features of action force of some tools and methods: distributed type of loads; rapidly changing force intensity; possibility of rocking sensitive device element; furthermore, different level of loads needs increased sensitivity on the one hand, and on the other hand, the universality of the device. The proposed device provides measuring constant, inconstant and harmonic loads in wide range as well as measuring concentrated and distributed forces with high accuracy. It allows registering information in real time, saving and processing data in a comfortable form. For example, the proposed dynamometer was used to measure action force of brush rotary disc polymer-abrasive tools on work surface. The tools based on polymer-abrasive fiber are used for finishing parts of complex profile, for trimming, cleaning, deburring, etc. They also have a light hardening effect. The results of research determined that force is 20…100 H depending on processing modes and tool options, therefore polymer-abrasive brushes can be used for thin-walled parts.

Natalia Honchar, Oleksiy Kachan, Dmytro Stepanov, Mark Kuchuhurov, Olena Khavkina

Implementation of Material Flow Simulation as a Learning Tool

The paper is focused on the possibility of implementation the simulation of the production process into the education process. Recently, emphasis has been placed on digitizing the production process, using Industry 4.0 and, last but not least, optimizing and minimizing production times. The paper is organized as follows into two sections. Section 1 describes the concrete possibilities of implementation the simulation software and Sect. 2 describes the evaluation of results on a concrete example from production process. After defining the same input data for 4 types of rolling bearings (production times, material flow and Gantt chart), the variety of simulation was followed in order to achieve an optimal distribution of production, transport and storage ratio in the 50:30:20 range. Due to the application of the simulation students are taught how to benefit of a thorough analysis of production process, and all the time the students are very close to the real work environment of the production company.

Jozef Husar, Lucia Knapcikova, Michal Balog

Process-Oriented Approach to Fixture Design

Machining of parts on the metal-cutting machine tools could not be ensured without the use of fixtures. They are an integral part of the closed-loop technological system “machine tool – fixture – cutting tool – workpiece” and make the significant impact on the accuracy and quality of machining of machine parts surfaces. The work presents the structural stages of computer-aided fixture design and determines the data flows between them to ensure the comprehensive approach. The process-oriented model of fixture design process has been developed, which provides the manufacturing analysis of the workpiece, synthesis and optimization of fixture configurations, verification of the mechanical system “fixture – workpiece” for set production conditions, and functional links and data flows between stages have been determined. The above-mentioned allows realizing a comprehensive approach to the computer-aided fixture design in multiproduct manufacturing.

Vitalii Ivanov

Technological Assurance of Complex Parts Manufacturing

The ways of intensification of machining complex parts of vehicles on the modern metal-cutting equipment were described. The classification of parts such as levers was developed on the basis of design and technological features. Based on the developed classification the structural code that allows to encode any lever design was proposed. The structural code can be used in computer-aided fixture design and in information retrieval systems for selecting optimal fixture for levers. The reasonability of intensification of parts machining such as levers was substantiated, the typical manufacturing process was analyzed, and opportunities for optimization subject to current trends in machining and technological capabilities of modern equipment were identified. The adjustable locating-and-clamping module characterized by high level of flexibility was proposed for CNC multiaxis machining operation. Comparative analysis of manufacturing processes by labor content, quantity of fixtures and machine tools, number of setups, and production area was performed.

Vladyslav Karpus, Vitalii Ivanov, Ivan Dehtiarov, Jozef Zajac, Viktoria Kurochkina

Modeling of Foundry Processes in the Era of Industry 4.0

The paper presents main areas of Industry 4.0 concept with regard to specificity and complexity of foundry processes. Data mining tools are discussed in terms of the possibilities and limitations of their application in Smart Factories. Data acquisition methods are described and the potential areas of restrictions in Internet implementation of things are identified on the example of foundry processes. The methodology of data preparation is also presented, including key tasks and actions to be taken, so that the collected production data are valuable from the point of view of Data Mining tools. As a result, the concept of CPS (Cyber-Physical Systems)/CPPS (Cyber-Physical Production Systems) tool allowing effective implementation of Data Mining tools in complex production processes is presented.

Jacek Kozłowski, Robert Sika, Filip Górski, Olaf Ciszak

Ansys Simulation of the Joint Strength with the Interference Fit in the Presence of the Shape Geometry Error

The effect of the shape geometry error on the strength of a cylindrical joint with interference fit was investigated. The strength of the joint without a geometry error was compared with the strength of the joint in the presence of conicity, saddle shape, barrel shape, ovality. The calculation is carried out by the finite element method in Ansys. It is established that for small-bore diameters the strength of a cylindrical joint with interference decreases significantly, i.e. one-third of the initial one. The most unfavorable is a saddle shape, followed by ovality and conicity, and the barrel shape does not lead to a significant decrease. For large diameters, the influence of the shape geometry error on the strength of a cylindrical joint with interference is less significant. It is recommended tightened standardization of the shape geometry error in manufacturing of parts of critical joints with interference.

Oleksandr Kupriyanov

Adaptive Profile Gear Grinding Boosts Productivity of this Operation on the CNC Machine Tools

The paper is devoted to solving an important scientific and technical problem of increasing the productivity of defect-free profile gear grinding on CNC machines through computer subsystems of grinding operation automated design, monitoring, and grinding diagnostics. The corresponding methodology and theoretical preconditions for these computer subsystems developments are provided to solve the following scientific problem. Despite of the increase in the productivity of gear grinding on CNC machines, a number of attendant factors have appeared that limit the gear grinding productivity: the time of the grinding stock measuring in the tooth spaces which is comparable with the time of gear grinding, the lack of methods for accounting the information about the grinding stock, etc. In this connection, the objective of the paper is to indicate the ways of increasing the productivity of the profile defect-free gear grinding on CNC machines. For this purpose, a set of purposeful methods and means of innovative adaptive gear grinding technology has been developed. For example, a method for restoring information about the grinding stock is proposed with a limited number of measurements to ensure, for example, that the feed can be switched from accelerated one to working and vice versa. Mathematical models have been developed to convert the grinding stock uncertainty into the deterministic value of the grinding wheel retraction from the workpiece, etc.

Vasily Larshin, Natalya Lishchenko

Provision of the Quality of Manufacturing Gear Wheels in Energy Engineering

Mathematical modeling of thermal processes during grinding and of the process of formation of residual stresses and cracks is done. On this basis the technique of calculation of thermal processes and of internal residual stresses arising during grinding of wheels made of cemented steels is offered. It is shown that the grinding temperature when machining gears from cemented steels should not exceed the temperature at which the reverse martensitic transformation occurs-the formation of austenite. The formed austenite during grinding does not completely turn into martensite, since the cooling temperature does not overlap the interval Ms-Mf as a result the so-called burnings of hardening are formed. Burnings of hardening 3–4 times reduce the strength and durability of the ground surface, and therefore of the whole part. On the basis of performed calculations, ways of improving the quality of manufacturing of work surfaces of teeth of tooth gears, which are used in aggregates of thermal and nuclear power plants, are proposed and substantiated.

Vladimir Lebedev, Vladimir Tonkonogyi, Alexey Yakimov, Liubov Bovnegra, Nataliya Klymenko

Combined Laser-Ultrasonic Surface Hardening Process for Improving the Properties of Metallic Products

Combined laser-ultrasonic hardening and finishing process of large-sized products using laser heat treatment (LHT) followed by the ultrasonic impact treatment (UIT) is proposed. In this study, a medium carbon and chromium tool steels were heat treated by a 1 kW fiber laser with scanning optics and heating temperature control system to improve their surface hardness. A number of experiments are carried out by changing the heating temperature and specimen feed rate while keeping a constant scanning speed and width to produce the hardened layers of different depths. After the LHT, the specimen surfaces were severely deformed by an ultrasonic tool equipped with a seven-pin impact head supplied by a 0.3 kW ultrasonic generator and controlled by a computer-driven machine to form a regular surface microrelief and compressive residual stresses. The results indicate that the combined treatments provide more than triple increase in the surface hardness and formation the compressive residual stresses. Additionally, the LHT + UIT leads to a formation of the regular surface microrelief with minimum surface roughness and high oil holding capacity.

Dmytro Lesyk, Silvia Martinez, Bohdan Mordyuk, Vitaliy Dzhemelinskyi, Oleksandr Danyleiko

Influence of the Scale Factor of Fibers and the Temperature of Structuring on the Physical and Mechanical Characteristics of Hemp Fiber Biocomposites

According to sustainable development approaches in the world, there are tendencies to save renewable resources, or resources with a long recovery time. This research aims to develop new composite materials based on the renewable resource in the form of hemp fibers. The article shows the results of research of mechanical characteristics (impact toughness, tensile strength, hardness) of polymer composite that is fiber-reinforced by technical hemp. The effect of size of fibers and method of structuring the polyester matrix on the mechanical properties is studied. The optimal composition of the composite, which provides better mechanical properties, is defined. It is determined that the investigated composites can be used as construction material based on renewable source.

Mykola Melnychuk, Oksana Andrushko

On the Application of N-2-1 Locating Principle to the Non-rigid Workpiece with Freeform Geometry

Fixture design for non-rigid workpieces is performed based on the N-2-1 locating principle (with N > 3 base locators). Determination of the position and orientation of the application points of the locators are among the most challenging processes that fixture designers are encountered with, especially in case of the freeform workpiece without specific datum features. In this paper, the N-2-1 locating principle has been applied to a non-rigid freeform workpiece which is chosen from the aerospace industry. In this regard, four distinctive locating plans have been designed by alternating of two parameters: the quantity of the base locators (N) and the position of the locating points on the base locating surface. Numerical analyses have been conducted using finite element software in order to investigate the effects of the mentioned parameters on the fixturing characteristics under the application of the clamping forces. The output parameters can be elaborated as workpiece deformation, displacements of the locating points, stress values and the reaction forces generated on the locating agents. The best locating plan has been chosen by the application of the suggested decision-making model by incorporation of the calculated fixturing characteristics. Based on the results, reductions of almost 41.6% and 66% were observed respectively on the workpiece maximum deflection and cumulative locating points’ displacements by switching from the 3-2-1 to the N-2-1 (with N = 6) locating system without sensible change in the stress values.

Hadi Parvaz, Seyyed Ali Sadat

Information and Communication Technologies Within Industry 4.0 Concept

Internet of Things provides connectivity and interoperability between transport entities, transported entities and product entities in Industry 4.0 concept. The market requirements are changing on daily basis and for the business processes of manufacturing organizations to be successful, it is necessary to link all the supply chain stakeholders and ensure their real-time informing, by forming an ecosystem for connecting stakeholders of Industry 4.0 concept. By implementing contemporary information and communication technologies in the production line it is possible to ensure the flexibility of production and adaptation of product entities to end user requirements. The problem of providing real-time information to all participants in supply chain has been identified by analyzing the traditional supply chain in the manufacturing industry. Based on the analysis of information and communication technologies in Industry 4.0 concept, the aim of this research is to propose optimal information and communication technologies for connecting stakeholders of logistic production chain. This extends the opportunity for all logistic production chain participants to inspect the stage of product entities from the stage of the development of product materials to the delivery stage of the product to the end users.

Dragan Peraković, Marko Periša, Rosana Elizabeta Sente

Computer Modeling Application for Predicting of the Passing of the High-Speed Milling Machining Hardened Steel

A high-speed milling of hardened steels at multi-coordinate machining centers in individual and small-series production has become of special interest because of the ability to provide high-quality characteristics of products. To ensure the surface layer quality with extremely small values of residual roughness, surface microhardness, and structural phase composition, a computer-aided simulation of the high-speed milling process by computational-logical algorithms based on the finite element method was performed. The experiments with computer simulation research of high-speed milling were done for two objectives: the process of rectangular cutting and the process of oblique-angled cutting of materials. Two-dimensional and three-dimensional computer modeling was used for the research. The connection between the chip formation process, the stress-strain state of the material, and the angle of inclination of the chip-forming groove of the end mill was established. The maximum value of the energy contribution to the cutting process was offered to choose for the determination of the maximum limit cutting conditions in high-speed milling.

Alexander Permyakov, Sergey Dobrotvorskiy, Ludmila Dobrovolska, Yevheniia Basova, Maryna Ivanova

Computer Simulation of the Processes of Mixing in Multilayer Nitride Coatings with Nanometer Period

Using the complex of methods for the structural state attestation in combination with the computer simulation and measurement of mechanical properties (hardness), the influence of the period Λ on the mixing process on the interlayer boundaries of multilayer coatings TiN/ZrN, CrN/ZrN and MoN/ZrN is studied. The coatings were obtained by the vacuum arc method on the upgraded “Bulat-6” installation. By means of the computer simulation method the depth of impact was estimated, which for the systems under investigation is about 2 and 3.5 nm, respectively. It is established that for the period Λ = 20 nm the highest hardness is 44 GPa. At Λ less than 20 nm, the hardness decreases, this can be related to the formation of a solid solution in the border regions due to the radiation-stimulated mixing. Computer simulation results obtained in the work allow to define the regimes for the optimal structural state. This is the basis of the direction of the structural engineering of nonequilibrium systems.

Oleg Sobol, Andrey Meylekhov, Anna Postelnyk

Model of Thermal State of the System of Application of Coolant in Grinding Machine

A high grinding performance and ensuring the accuracy and quality of processing depend on a stable thermal regime in the cutting zone, which is carried out by efficient removal of the released heat. Application of lubricating and cooling fluid allows reducing the power and cutting forces, accelerates heat transfer, provides a reduction in temperature in the cutting zone. It’s found out, that the most instability is characteristic for the heat entering the machine tool from the coolant system. Potentialities of decreasing of heat fluxes influence at the grinding machine on the accuracy by improving cooling ability of coolant tank are researched. The heat exchange processes in the coolant tank of the grinding machine are studied. A mathematical model describing the temperature regime of coolant in the grinding machine tank is proposed. The model makes it possible to estimate the steady-state and non-stationary temperatures of the coolant in the tank, depending on the course of the stages of the grinding cycle and to define the rational volume of the coolant, considering the cooling of cutting zone, the grinding parameters, and the characteristics of the grinding wheel. The dependence of the value of the average coolant temperature in the grinding machine tank from volume of coolant is determined.

Mykhaylo Stepanov, Larysa Ivanova, Petro Litovchenko, Maryna Ivanova, Yevheniia Basova

Technology of Effective Abrasive Jet Machining of Parts Surfaces

Presented scientific work is devoted to increasing the efficiency of abrasive jet machining through the development and implementation of a new, wear-resistant and progressive abrasive jet tool, namely a new designed assembled Venturi type nozzle. A developed design of a nozzle provides the formation of a special air layer on its internal working surface, which allows significantly decrease the contact of the abrasive air blast with the working surface of the nozzle, which increases its durability and the efficiency of the abrasive jet machining. Such kind of effect was reached by using a permeable porous insert in the narrowest part of Venturi type nozzle. An additional air flow is fed in radial direction to the outer surface of the insert and then penetrates through porous wall to the inner working surface of the nozzle. The desired design of developed product was obtained using titanium powder metals which were pressed and sintered in conditions of self continues high temperature synthesis because of its energy-efficient properties. Besides, if one of components of assembled nozzle is worn off, it is easy to fix by replacing to a new one.

Viktor Sychuk, Oleg Zabolotnyi, Dmytro Somov

Choice of the Optimal Parameters of the Ultra-Fine Grained Cooper Machining

This article is focused on the features of the structure of ultra-fine grained metals and the influence of the machining on its changes. The search for optimal parameters was carried out for machining of pure copper, obtained by the method of several plastic deformations. The objective function, which includes a new criterion of optimization, was proposed. Limitations of the function for turning ultra-fine grained copper were obtained from experimental data. As a criterion of optimality, a general combining criterion is proposed, which is based on the linear convolution, two particular criteria the productivity and size of the grain size of nano- and ultra-fine grained metals, each with its own weight coefficients. The optimization problem was solved by the penalty function method in the MATLAB software environment using the method of unconditional mini-mization of several variables. Optimal decisions on the selection of the cutting speed and feed during the rotation of ultra-fine grained copper with different initial grain sizes are obtained.

Anastasiia Symonova, Valerii Havin, Dmitrii Savelov

Obtaining of Porous Powder Materials by Radial Pressing Method

The article presents the results of theoretical and experimental investigations of the radial-isostatic pressing process of powder materials (PM) in order to improve its effectiveness, to create the new and improve the existing technologies, equipment, tools and PM with the improved properties. For analytical description of the pressing processes we propose a new improved equation of pressing, which takes into account the properties of PM, powder consolidation during pressing, the loading schemes and allows general authentical description of the deformation behavior of the porous material. We improved the construction of the machine press-block for dry radial-isostatic pressing of enclosed volume and also developed a number of new technical solutions which can solve the problem of obtaining high-quality and long powder products (simple and complex shapes) with a uniformly distributed density by volume. Proposed solutions also allow reducing the volumes of intermediate environments, power inputs of the pressing process, sizes and metal content of equipment, costs, which raises the productivity of work and reduces the cost of manufactured products.

Oleg Zabolotnyi, Viktor Sychuk, Dmytro Somov

Methods for Calculating the Grain Boundary Adsorption Capacity of Nanostructured Copper Based Condensates

The structure of vacuum Cu-Ta and Cu-Mo condensates in the form of foils approximately 50 μm thick was studied by transmission electron microscopy and X-ray diffractometry. The samples were obtained by electron-beam evaporation from various sources in vacuum of ~10−3 Pa. It is established that alloying of copper condensates with tantalum or molybdenum in the amount of 0.4–0.5 at. % disperses the grain structure of copper matrix from micro- to nanoscale dimension. It is shown that this effect is due to the blocking effect of adsorption layers of tantalum or molybdenum atoms formed on the surface of growing copper grains during the condensation of two-component vapor. Based on the experimental data and theoretical calculations carried out in different approximations, the conclusion about the monolayer character of grain-boundary segregations of tantalum or molybdenum atoms on the grain boundaries of copper matrix was made. Numerical methods for calculating the concentrations of tantalum or molybdenum that are necessary for the formation of monoatomic adsorption layers at grain boundaries of matrix metals of specified sizes are developed. Concentration dependencies of grain sizes of copper matrix calculated theoretically by the proposed method are in good agreement with the experimental data.

Maria Zhadko, Oleg Sobol, Galina Zelenskaya, Anatoly Zubkov

Investigation of the Influence of Electro-Impulse Current on Manganiferous Liquid-Alloy

The article shows that for improving the quality of castings, more and more often, technical solutions are used related to the influence of electric current on the melt during its crystallization. The positive results of such a modification are improved processes of heat and mass transfer and structuring. However, these results only concern the electrical treatment of non-ferrous metals and alloys, as well as some castings. The influence of the electric current limits on the degree of modification of manganese-containing steels during their crystallization in the foundry, as well as on the physical and mechanical properties of the casting requires careful research that would be close to real conditions. The authors compared the macro and microstructures of steel 35GL doped with manganese and modified during crystallization in the foundry form of the electro-impulse current with different current parameters: intensity, duration of impulses, frequency, squinting. It has been established that the modification of an alternating polarity with an electric pulse current of more than 10–3 s, a frequency of 5–33 Hz, a force of 30–40 A, a vacuum of 5–24, at a voltage in the power line of 180–240 V provides a reduction in structural inhomogeneity (the crystallite of the metal base and manganese carbides are reduced respectively from 280 to 82–85 microns and from 6.7 to 0.3–0.5 microns). These structural changes lead to a significant increase in the basic mechanical properties of cast structural steel 35GL: strength limits – 9%, impact strength – 21%, hardness (HB) – 6%.

Olena Zhbanova, Levan Saitgareev, Igor Skidin, Nonna Shapovalova, Genadiy Gubin

Forecasting Real Option Price Model by Means of Evolutionary and Genetic Algorithms

Research goals and objective: to predict real option prices using evolutionary and genetic algorithms which affect the accuracy of price forecasting. The object of research: real option price model. The subject of research: forecasting evolutionary and genetic algorithms for real option price model. Research methods are genetic algorithm, evolutionary algorithm, statistical technique. Results of the research: in options trading one of the main tasks is to determine the fair price option, using which we can estimate what options are undervalued, and which ones are overvalued at the moment. The decision on the purchase or sale of a particular option is made according to these algorithms. In this paper we apply genetic and evolutionary algorithms in the areas of financial instruments in order to create software intended for analysis and forecast of real price option.

Mykyta Zubrii, Anastasia Mazur, Vitaliy Kobets

Mechanical Engineering

Frontmatter

Experimental Study of the Power Characteristics Influence on the Hydraulic Efficiency

The hydraulic unit of rotation control system is improved. It is based on the use of a hydraulic distributor with a hydraulic vibration circuit and the injection of a hydraulic feedback for pressure. Due to this, the efficiency during winding operations increases. A model of the experimental installation for hydraulic unit of rotation for winding is developed and made. It provides a constant wire tension force. Hence, the hydraulic stiffness and reliability are increased. The choice of control and measuring equipment and experimental data processing methods are substantiated. The influence of the working parameters for hydraulic unit for winding of the electric motors wound on its efficiency is investigated. The results of a two-factor active experiment are presented. It was conducted using a rotatable plan of the second order. The response function is obtained and its adequacy is proved. The graphic dependencies of the hydraulic motor shaft moment from the wire tension force at different values of its shaft rotational speed are built. The optimum values of the wire tension force and the hydromotor shaft rotation frequency are defined. The hydromotor linear mathematical model is developed. The operating time for the hydraulic unit of rotation is set.

Pavlo Andrenko, Iryna Grechka, Sergey Khovanskyy, Maksym Svynarenko

Increase of Efficiency of Turbine Setting Based on Study of Internal Flows

Turbo efficiency largely depends on the internal overflows. Labyrinth seals are used as internal ones. To determine their flow characteristics a simplified calculation model of the opening with a sharp edge is used. It is supplemented with the experimental coefficients obtained under conditions which are significantly different from as-build. These ratios do not take into account the ring gap shape, flow vortexes on the inlet, eccentricity, shaft rotation, scale factor. When designing, simplification data do not allow using a labyrinth seal with a minimum leak value. The aim of this work is to upgrade knowledge about the workflow in the labyrinth seals using the modern methods of computational fluid dynamics (CFD), which are going to increase the efficiency of the internal labyrinth seals. At the same time, the numerical and experimental studies of the labyrinth seal element were carried. The research tasks are to establish the correctness of CFD methods application for studying the flows in the essentially narrow slits and obtaining the visualizations of the workflow under various geometric and regime parameters, to give practical recommendations on the design of such seals. Velocity fluctuations in the labyrinth seal are identified. They result from the uneven distribution of pressure along its length. The seal design with a variable pitch that allows reducing the leakage to 30% is proposed. Shaft rotation causes leakage reduction to 20%.

German Bondarenko, Serhiy Vanyeyev, Vadim Baga, Tetiana Rodymchenko, Iryna Bashlak

Effect of Abnormal Operation of Turbine Generator on the Resource of Steam Turbine Shafting

The results of evaluation of fatigue damage caused by the intense vibrations of steam turbine shafting at abnormal operation of turbine generator are presented. The abnormal operation of turbine generator may be caused by the sudden short-circuit in turbine generator or by the connection of turbine generator to the electric network. The evaluation of fatigue damage is based on the 3D finite element model of turbine shafting of steam turbine K-215-130. The fatigue properties of rotor steel were experimentally determined and used in the model. The fatigue damage of steam turbine shafting was evaluated for different scenarios of connection of turbine generator to the electric network and in account for experimentally determined damping properties of turbine shafting in operation.

Anatoliy Bovsunovsky

Experimental Investigation of Physical and Tribological Properties of Engine Oil with Nano-particles Additives

Experimental Investigation of physical and tribological properties of engine oil was performed on SAE20W40 lubricant containing CuO and FeO nano-particles and their combination (content of metal 0.875 g/350 ml of oil). This presents an analysis of the variation in properties of lubricants by adding nano-particles and further enhancement in its operational quality. This work also presents a review of the addition of copper and iron metallic nanoparticles in engine oil and the evaluation of changes in their respective physical and tribological properties. Later analysis of the variation in tribological properties has been carried out by conducting tests on the bearing test apparatus. FFT (Fast Fourier Transform) and other operational parameters are used to analyse vibration characteristics for different samples of lubricants. Through comparative analysis, the use of the base oil (SAE20W40) with the mixture of CuO and FeO provides the most effective improvement of physical properties via viscosity, flash and fire point as well as vibration in tribological properties.

Manoj K. Gaur, Sumeet K. Singh, Akash Sood, Dharamveer S. Chauhan

Simulation and Analysis of Passive vs. Magneto-Rheological Suspension and Seat Dampers

This paper presents some analyses and simulation results of the passive and magneto-rheological (MR) suspension and driver’s seat dampers. The damper with the MR liquid is modeled via the Bingham model due to its simplicity and high efficiency in comparison with other models. The simulation models of the passive and MR damper suspension and driver’s seat models are developed in MATLAB/Simulink. Two road profile data sets are used in simulations, one of which is the road roughness data, collected from the roads, that is interpolated with respect to the vehicle speed, and the time spent to cover the chosen road distance. The other is the Heaviside step function generated numerically. The numerical simulation results have shown that the MR based suspension and seat dampers have outperformed the passive suspension and seat dampers considerably.

Sulaymon Eshkabilov, Hamdam Jumaniyazov, Davron Riskaliev

A Semi-implicit Generalized Finite Differences Approach to Simulate Natural Convective Viscous Flows

The purpose of this work is to carry out a Lagrangian semi-implicit Generalized Finite Differences (GFDM) implementation to simulate transient natural convective viscous flows. The solution of the incompressible Navier–Stokes equations is formulated through the first order Chorin’s projection method whilst the energy equation is implicitly discretized with the first order Euler scheme. The semi-implicit set of discretized equations is solved with the Finite Point set Method where the incorporation of the boundary conditions is done in a direct and simple manner without requiring any special treatment or stabilization. The main features behind this mesh free approach as well as details of its implementation are shown. The suitability and the accuracy of this approach for the numerical simulation of the transient natural convective viscous flows are demonstrated through the solution of the two-dimensional benchmark problem. Finally, the stability of this FPM approach is studied through the variation of parameters in the two-dimensional benchmark problem, which shows that this formulation is a promising numerical tool for the simulation of the processes involving convective thermal flows.

Felix Raymundo Saucedo-Zendejo, Edgar Omar Resnediz-Flores

Optimal Management of Small Hydroelectric Plants Power Generation in Local Electrical Systems

The number of renewable energy sources (photovoltaic power plants, small hydroelectric power plants and others) is growing rapidly. They transfer the generated electrical energy through the distribution networks of power supply companies. Therefore, the problem of calculating the normal modes of such electrical networks is urgent. This makes it possible to investigate the influence of renewable energy sources on the losses of electric power in distribution electrical networks. The given paper presents a mathematical model of active power losses of local electrical systems - electrical systems of power supply companies. The sources of electricity for such systems are not only powerful electric stations, but also renewable energy sources. Often these are distributed sources of energy. That is why optimal management of such sources is complex. The article shows the determination of insensitivity zones of the optimal points deviations in which the power fluxes are distributed to the change in the load power and generation in the nodes of local electrical systems. The mathematical expression is proposed where similarity criteria are used, it allows to analyze the influence of generation of the investigated renewable energy source on the losses of active power. The significance of these similarity criteria can be determined from the optimality conditions of the dual criterion programming problem with respect to the direct problem. It is expected that the account of calculation results of dead zones will enable to determine a renewable energy source, for instance, a small hydroelectric power station. Control of the generated power of the selected power plant at this time provides minimal losses of electrical energy of distributed electric networks.

Petro Lezhnuk, Olexander Rubanenko, Iryna Hunko

Effect of Phase Composition on Cavitation Resistance of Ceramics

The results of the tests of technical ceramics in conditions of cavitation wear are presented. The ultrasonic frequencies of 22 and 44 kHz were used. The influence of the structural constituents of ceramics on the rate of failure is shown. Wear features are noted. The effect of additives on the durability of materials is analyzed. The nature of ceramics wear and its similarity to the mechanism of damage of metals are demonstrated. It is proposed to use the critical destruction power for the determination of intensity of ceramics wear. On the basis of structural energetic theory, an adapted formula is proposed for comparing the intensity of destruction of ceramics of different types. The results of calculations are correlated with the experimental data. In addition, the proposed approach makes it possible to use for the known materials the known dependences of the evaluation of the wear resistance of metals.

Alexander Litvinenko, Yuriy Boyko, Bohdan Pashchenko, Yuriy Sukhenko

System Dynamics Model for Continuous Review Inventory System in Demand Shock Conditions

This paper deals with applying a control loop based on PID controller algorithm to dynamically setting the components of the continuous review system (Q-system) for inventory management to avoid demand shock unrequired influence on a customer service level. Through Vensim software platform, the system dynamic model of feedback system was developed, consisting of the Q-system for single echelon logistics and PID controller. Finally, operational performance results are analyzed using data of performed simulation experiments.

Sławomir Luściński, Dariusz Dobrowolski

Numerical Study of Outlet Blade Angle Effect on Impeller Characteristics of Double Entry Centrifugal Pump

The characteristics of pump performance are depended strongly on the impeller geometry. Changes in some impeller geometric parameter can improve pump performance. It is well known that outlet blade angle is one of those parameters, which has significant effect on the impeller work characteristics. This work is connected with the effect of blade outlet angle changes on the performance of double entry centrifugal pump impeller. This process is investigated via Ansys computational fluid dynamics (CFD) software. CFD method can predict well the complex internal flows in centrifugal impellers. The present paper describes the simulation of four impeller working process. The outlet blade angle was changed from 26° to 32° while all other geometrical impeller parameters were kept constant. The head-flow rate, hydraulic efficiency-flow rate and shaft power-flow rate curves are compared and discussed for each impeller. The obtained results show that even insignificant changes of the blade outlet angle effect on the impeller performance.

Viktoriia Miltykh, Mykola Sotnyk

Application of Artificial Neural Network for Identification of Bearing Stiffness Characteristics in Rotor Dynamics Analysis

In this article the implementation of the mathematical model for rotor oscillations on non-linear bearing supports for the multistage centrifugal compressor is considered by using the computer program “Critical frequencies of the rotor”. It realized the finite element mathematical model, which allows taking into account the non-linear dependence of bearing stiffness on the rotor speed, as well as gyroscopic moments of inertia of impellers and shell-type parts. The artificial neural network “Virtual Gene Developer” software is proposed for evaluating the operating parameters of the approximating curve “bearing stiffness – rotor speed” by the dataset of numerical simulation results in the abovementioned software. Actual parameters of non-linear bearing stiffness are obtained by the results of the experimental research of rotor critical frequencies for the multistage centrifugal compressor 295GC2-190/44-100M on the experimental accelerating-balancing stand “Schenck”. The main advantages of the proposed approach and methodology for application of Artificial Neural Networks are stated.

Ivan Pavlenko, Vitalii Simonovskiy, Vitalii Ivanov, Jozef Zajac, Jan Pitel

Movement of the Particle on the External Surface of the Cylinder, Which Makes the Translational Oscillations in Horizontal Planes

Differential equations of relative displacement of a particle on the external surface of an inclined cylinder, which performs oscillatory motion, are obtained in the article. All points of the cylinder describe circles in horizontal planes. The equation has been solved numerically and trajectories of relative motion of a particle along the cylinder surface have been constructed. Graphs of other kinematic characteristics in time function are presented. Partial cases, when the axis of the cylinder is located horizontally or at an angle of friction to the horizontal plane, are considered. An experimental research to determine the soil separation efficiency by a sloping cylinder, which performs fluctuations, depending on the influence of individual factors (the coefficient of friction of the soil and the angle of inclination of the cylinder) was conducted in the article. After processing the experimental data, the regression equations were obtained to determine the separation quality and the response surface was constructed.

Sergiy Pylypaka, Mikola Klendiy, Tatiana Zaharova

Influence of the Passive Flow Initial Parameters on the Efficiency of Liquid-Vapor Ejectors

The article deals with the issue of creating a vacuum in various industries and equipment using two-phase jet devices, namely liquid-vapor ejectors working on principle of stream thermal compression. The principle of stream thermal compression implies boiling of the working fluid in the expanding part of the active flow nozzle. The influence of the initial parameters of the passive flow on the efficiency of the mixing process is based on extensive literature analysis of the works of modern domestic and foreign authors. The character of the influence of temperature, relative humidity and the content of the passive flow at the entrance to the receiving chamber on the geometric and regime parameters of the mixing chamber is established. The results of numerical and experimental investigations of the influence of the passive flow initial parameters on the efficiency of liquid-vapor ejectors are presented. Exergetic analysis of the efficiency of these devices with various passive flow environments is performed.

Serhii Sharapov, Vyacheslav Arsenyev, Maxim Prokopov, Viktor Kozin

Constitutive Equation for Numerical Simulation of Elastic-Viscous - Plastic Disperse Materials Deformation Process

During the investigation it was made the methodology of elastic - viscous - plastic disperses materials (DM), deformation processes, creation of constitutive equation. The two levels of DM structural analyses are used, such as microanalysis (separated micro-fragment (particle) of a disperse system consideration) and macro-analysis (the parameters averaging the representative element macro volume). It is considered that the parameter of the local (at micro level) energy deformation speed of the solid phase with its subsequent over the representative element volume is averaged. The constitutive equation general structure is formulated by the components of stress and deformation rates tensors due to the chosen material model. The peculiarity of this model is that the equilibrium flow concept elastic-viscous-plastic material is an alternative to its elastic-plastic deformation The proposed equations are suitable for their effective practical using for digital models creation that based on existent software for the of equilibrium processes of compact materials deformation finite-element analysis. It can be used for calculating of technological processes and designing equipment of food and other productions.

Evgenii Shtefan, Bohdan Pashchenko, Serhii Blagenko, Serhii Yastreba

Determination of Transfer Functions for Electrohydraulic Servo Drive of Technological Equipment

An electrohydraulic servo drive with throttling regulation of technological equipment is considered. The following basic elements are distinguished in the drive: hydraulic cylinders, the electrohydraulic amplifier including the electromechanical transducer and the hydraulic amplifier, the feedback gauge, the electronic block. To study the dynamic characteristics of the drive a typical mathematical model of non-stationary work processes occurring in the drive is presented. The linearization of the mathematical model is carried out, the structural scheme of the drive is constructed, the transfer functions are obtained for the control signal and the loading influence. The main parameters of the drive are the time constant of the control winding, the time constants of the electrohydraulic amplifier, the time constants of the hydraulic cylinder, the coefficient of relative damping of the hydraulic cylinder, the feedback coefficient, the drive transfer coefficient by the control signal, and the drive transfer coefficient by the loading influence. The proposed linear mathematical model and transfer functions are adapted to the drives of the technological equipment. The main advantage of the presented mathematical description of the characteristics of the electrohydraulic servo drive with the throttle regulation is the ability to perform the stability evaluation, quality of control and correction of the dynamic properties of the drive using the technical certificate data of the drive elements and devices.

Volodymyr Sokolov, Oleg Krol

Influence of the Stochastic Nature Parameters of Throttle Channels on Characteristic of Automatic Balancing Device of the Centrifugal Pump

Automatic balancing device is used to balance the axial force. Moreover, this device acts as an end-seal of centrifugal pump and about 5% of whole power can be lost on it. Operating characteristics of automatic balancing device are determined by cylindrical and face throttles geometrical characteristics that have stochastic nature. It caused by the real constructional form of inlet in annular and face throttles, possible deformations, initial manufacturing, and installation misalignment and deviations depend on different stochastic factors. Using the example of static characteristic calculating of an automatic balancing device for a centrifugal pump, it is shown that considering the stochastic nature of the geometric characteristics of the throttle channels, the losses in the face throttle, gives a random character to the variation of the balancing device parameter. Obtained results showed not only the qualitative but also quantitative influence of the random changes of the hydraulic resistances on the values of the balancing axial force and the face gap (about 10–13%). The deviation of the gap value from the calculated one leads in any case to negative consequences: a decreasing - to scuffing and a complete failure of the whole device, increasing - to reducing the volume efficiency of the pump. Presented calculating technique can be recommended as easy-to-use and simple way to consider local losses in automatic balancing device.

Yuliia Tarasevych, Nataliia Sovenko, Ievgen Savchenko

Comparative Tribological Tests for Face Impulse Seals Sliding Surfaces Formed by Various Methods

The article shows the analysis of change of face impulse seal rings, which are completely made of expensive wear-resistant materials, such as tungsten carbide, silicon carbide, various kinds of graphite on rings, which are made of less expensive but not less qualitative materials. It has been established that the seal rings surfaces are in contact for a very short time, only at the time of starting and stopping the unit. Therefore, it is proposed to use metal base-coating composite materials for such surfaces, which combine the protective properties of coatings and the mechanical strength of the surface base. Metallographic and tribological research were carried out on samples of heat-resistant steel 38X2MUA (41CrAlMo7), high-speed steel P6M5 (HS6-5-2C) and stainless steel 12X18H10T (X6CrNiTi18-10KT). Various variations of the samples heat treatment were used: steel 38X2MUA after thermal treatment, thermal treatment + ion nitriding, thermal treatment + carbonitriding; steel P6M5 after thermal treatment, thermal treatment + condensed ion bombardment; steel X6CrNiTi18-10KT after thermal treatment; thermal treatment + condensed ion bombardment. It was found that the greatest thickness of hardened layers (up to 500 μm) is achieved with hardening of 41CrAlMo7 steel by ion nitriding and carbonitriding methods; the greatest of the surface layers microhardness for samples of steels HS6-5-2C and X6CrNiTi18-10KT, which were subjected to hardening by the method of condensed ion bombardment (18.3 and 16.4 GPa, respectively); The lowest frictional force was shown in samples of steel 41CrAlMo7, slightly higher in high-speed steel HS6-5-2C, and the highest in steel - X6CrNiTi18-10KT.

Viacheslav Tarelnyk, Ievgen Konoplianchenko, Vasyl Martsynkovskyy, Aleksey Zhukov, Piotr Kurp

Effect of the Parameters at the Inlet to the Rotor of the Jet-Reactive Turbine on Its Efficiency

The article shows that the amount of motive force of the traction nozzle is directly affected by the total pressure recovery factor in the flow part of the jet-reactive turbine and its elements, which characterizes the energy losses. The effect of various gas-dynamic and geometric parameters on the total pressure recovery factor in the flow part of the jet-reactive turbine is studied. In order to increase the total pressure recovery factor in the flow part of the jet-reactive turbine, it is necessary to install a diffuser sleeve with a cylindrical part where there is a transition from a supersonic flow velocity to a subsonic flow and a diffuser part where a further subsonic flow velocity decreases. Element-by-element analysis of gas flow in the flowing part of the jet reactive turbine with a diffuser sleeve at the entrance to the rotor is performed. It is established that the reduced flow velocity at the inlet to the rotor should be as low as possible, based on the location of the shock wave in the inlet part of the diffuser sleeve, and the opening angle of the diffuser part of the diffuser sleeve should be no more than 10°.

Serhiy Vanyeyev, Stanislav Meleychuk, Vadim Baga, Tetiana Rodymchenko

Chemical Engineering

Frontmatter

Modeling of the Heating for Cladded Powder in Plasma Jet at Spraying of Coating

The paper is devoted to solving the problem of determining the temperature of cladded particles with a shell in a plasma jet taking into account the change in their aggregate state. The features of heating of the cladded particles during plasma spraying of functional coatings are considered. The analytic solution of the boundary problem for the heat equation in the case of a variable temperature of the plasma jet, which was approximated by cubic splines, was obtained. The mathematical model of heating of powder particle with a sheath during plasma spraying taking into account the time matching of plasma jet temperature and particle is generalized. Formulas for determining the melting time of the metal sheath and the ceramic core were given. Influence copper sheath thickness on heating of alumina kernel of the cladded particle by an analytical solution is set. The results of testing coated samples confirmed that the developed cladded powder improves the physical and mechanical properties of the plasma sprayed composite coatings.

Andrii Andreytsev, Igor Smirnov, Andrii Chornyi, Mykhailo Yelysieiev, Nikolay Dolgov

Information Support of Optimization Calculation of Vortex Type Granulation Devices

The paper studies the hydrodynamic conditions of gas flow motion and vortex granulator workspace design optimization. A comprehensive approach for determination of the hydrodynamic characteristics of a vortex gas flow and their visualization is proposed. The mathematical approach, based on Reynolds equations for turbulent flows solution, is presented. The mathematical model of equations solution with the definition of gas flow velocity components in any point on the radius and height of vortex granulator is obtained. The value of gas flow components of velocity, received by the results of analytical solution, and experimental data has a high degree of compliance. There is mutual rejection that numerical value of velocities and overall graphic image of diagrams of components of gas flow velocities have the same character. For rate and radial velocity components of gas flow for the initial conditions and changing set of geometrical and technological conditions does not cause such significant change of quantitative distribution value along the radius and height for angular velocity component gas stream. The obtained results form the basis of original algorithm for calculating of vortex granulator hydrodynamic calculation and its basic dimensions optimization selection.

Artem Artyukhov

The Carrier Development for Biofilms on the Basis of Technogenic Wastes for Pollutants Treatment in the Environmental Protection Technologies

The advantages of the environment protection systems operated with the use of cell immobilization were analyzed. This paper focuses on the determination of the formed features of mineral carrier based on the technogenic secondary resource use (phosphogypsum and fly ash) for hydrogen sulfide removal technologies. The results of research show that oxygen diffusion was difficult at a depth of penetration of a bacterial matrix around 1.5–2.5 mm in the phosphogypsum granules of large size (diameter > 5 mm). The main processes of aerobic conversion occurred in the granules from 3 to 5 mm with the oxidation of sulfur compounds, hydrogen sulfide and sulfur oxides, to produce biosulfur. The depth of bacterial matrix penetration increased with diameter increase, because the components of the granules were transformed as a mineral substrate. Various mechanisms of fixing biomass on carriers based on technogenic mineral resource was studied for assessment of biomass productivity out of the carrier layer. The optimal hardening time for the granules stabilization was determined under an internal interlayer of the immobilized biomass conditions and the efficiency of sulfide oxidation was estimated.

Yelizaveta Chernysh, Leonid Plyatsuk

The Use of Waveguides with Internal Dissectors in the Process of Regeneration of Industrial Adsorbents by Means of the Energy of Ultrahigh-Frequency Radiation

Waveguide structures that can be used in the adsorption columns of compressed air dehumidifiers for the purpose of molecular sieve regeneration by using microwave energy in the process of desorption are considered. Mathematical models of the electromagnetic field in waveguides of various designs are constructed. A study was carried out to select the best design of the waveguide irradiating the volume of the adsorbent in the cavity of the adsorption tower of the adsorption desiccant. In general, the conducted studies have shown the possibility and expediency of using X-shaped waveguides with excitation from an exciting waveguide or a coaxial cable in the construction of adsorption columns with microwave regeneration of the adsorbent, as well as the applicability of an internal dissector installed inside the waveguide to create a traveling wave in the column cavity with different the intensity of the microwave radiation of the electric field in order to increase the uniformity of the influence of microwave energy on the volume of the adsorbent. Theoretically, the possibility of using internal dissectors has been confirmed in order to increase the uniformity of the distribution of microwave energy in the cavity of the adsorption column of the desiccant. The presented theoretical experiment opens the prospect for further practical studies of the effect of microwave radiation on the process of molecular sieve desorption under conditions of the adsorption column operation as part of the adsorption dryer, and shows the creation of an effective innovative sample of industrial equipment.

Sergey Dobrotvorskiy, Ludmila Dobrovolska, Borys Aleksenko, Yevheniia Basova

Obtaining of Multilayer Granules in a Vortex Gas Flow: Automated Complex for Technological Calculation

The article describes theoretical bases of the process of obtaining multilayer granules and mathematic model for software realization. The program Multilayer Granules® that carries out technological calculation of the solution for the filming process of the granule surface, is represented in the article. The optimal construction of the vortex granulator is achieved, based on technological calculation results of the granulating process and hydrodynamic calculations, using the computer modeling (based on the author’s model for calculating the hydrodynamic conditions of gas flow and granules movement, classification and separation processes of granules in a vortex granulator, kinetics of granules heating and removing moisture from the granules). The calculation results become the base for vortex granulators engineering calculation methodology to obtain the multilayer granules. The work shows industrial application of the investigated software products – production of the porous ammonium nitrate (PAN). A porous multilayer granules sample, obtained in the vortex granulator, is demonstrated in the article. Multilayer Granules® allows conducting optimization of vortex granulator calculation according to the criteria of minimum required residence time of granules in device workspace.

Andrii Ivaniia, Artem Artyukhov

Simulation and Design of Welded Plate Heat Exchangers with Channels of Different Corrugation Height

A method of using a different height of the corrugation along the side of the heating and incalescent heat carriers to intensify the heat transfer process in the channels of heat exchangers with a circular plate is proposed. The use of such construction leads to equalization of the flow rates in the channels, a reduction in the number of channels, and an increase in the shear stress on the heat transfer surface of the plates. The search for the solution is based on the determination of the velocity of the heat carriers in the channels of the heat exchanger, when the pressure drop in the channels is complete satisfaction. The algorithm for solving the problem of finding the best solution is combinatorial. The problem of finding the optimal integer value (number of plates) is solved on a limited set of possible combinations of continuous design parameters – the height and angle of corrugation. The influence of the geometric parameters of the corrugation on its heat transfer capacity is investigated. A specific application for the calculation of the heat exchangers with different height channels of the corrugation was considered.

Gennadii Khavin

Granulation Process of the Organic Suspension: Fluidized Bed Temperature Influence on the Kinetics of the Granule Formation

The authors of the article present and prove the possibility of reducing the economic and environmental indicators in the processes of mineral fertilizers granulation by means of recycling and using organic agricultural waste. It is shown that such waste products are in the form of very moist suspensions, therefore, in order to minimize energy consumption for their processing, the optimal technology for granular product preparation is granulation in the fluidized bed apparatus. For this purpose there has been conducted the physical modelling of the granule formation process and one found out the conditions of suspended layer formation, which determine the nature of the dispersed suspension and dispersed solid phase interaction. One has experimentally established the temperature regimes of organic suspensions granulation and determined the operating parameters of the process. The kinetics of coarsening of granules was studied depending on the temperature of dehydration of organic suspensions. Analytical dependencies that are determined by the heat transfer coefficient are obtained to determine the time and temperature of granule heating.

Ruslan Ostroha, Mykola Yukhymenko, Andrii Lytvynenko, Jozef Bocko, Ivan Pavlenko

Design and Study of Conical Pressure-Swirl Atomizers

The paper shows the results of experimental studies for two-phase swirl atomizers with two inlet ports different in terms of design. The effect of volumetric liquid and gas flow rate and the height and diameter of mixing chamber on the discharge coefficients, histograms, radial distributions of mean droplet diameters in the drop stream and the mean Sauter diameter were determined. The studies were conducted within the air flow rates not exceeding 5.6·10−4 [m3/s] and water flow rate 1.11·10−5 [m3/s]. It was shown that the discharge coefficient increases with the higher Reynolds number for the liquid and decreases with the higher gas flow rate. The increased liquid flow rate caused greater drop diameters and increased gas flow rate allowed to obtain droplets with smaller sizes. The value of Sauter means that the diameter is dependent on the ratio of height to the diameter of mixing chamber. The rapid increase in the mean droplet diameter occurs above the value of H S /D S  ≈ 2.75. It was further noted that higher gas flow rate within the aerosol axis gives rise to the drops with smaller diameters and there is a clear difference in the size of droplets between the central stream area and its edges. In addition, the empirical correlation was proposed for the discharge coefficient as a function of work characteristics and geometric dimensions of the atomizer. The obtained data can be used for designing new atomizers and are essential from the viewpoint of agriculture or combustion processes.

Marek Ochowiak, Olha Lytvynenko, Sylwia Włodarczak, Magdalena Matuszak, Andżelika Krupińska

Investigation of the Process of Saturation of the Filter Liquid of Soda Production with Ammonia and Carbon Dioxide in the Production of Ammonium Chloride

This paper is focused on the saturation process of the filter liquid of soda production with ammonia and carbon dioxide in the production of ammonium chloride. In the world practice, there are many ways to produce ammonium chloride from the filter liquid. These ways of ammonium chloride production suppose progressive saturation of the filter liquid with ammonia and carbon dioxide. This paper is focused on identifying the optimal conditions for conducting the process. For this purpose, the saturation of the filter liquid with gases both in sequential and simultaneous feeding to the apparatus at total flow of 1.5–6.0 dm3/min and at temperature of test solution of 15–50 °C was studied. The comparison of material balances of consecutive and simultaneous supply of ammonia and carbon dioxide shows that the process in one apparatus allows reducing the gas consumption factor by approximately 14.4%. Thus, as a result, the method for simultaneous supply of gases is proposed in order to obtain high degree of saturation with ammonia and carbon dioxide of the filter liquid followed by the production of ammonium chloride by the salting out method.

Inna Pitak, Valery Shaporev, Oleg Pitak, Alina Hrubnik, Viktor Moiseev

Modelling of Liquid’s Distribution and Migration in the Fibrous Filter Layer in the Process of Inertial-Filtering Separation

The obtained solution of the mathematical model of liquid’s distribution and migration in the filter layer as flow model in the fibrous environment, which describes the non-pressure filtration motion in the gravity field of the separated liquid film from the gas-drop flow, allows to determine the saturation conditions of the free volume of the filter layer, distribution of speed and pressure under the conditions of free liquid’s movement in the filter layer, as well as to calculate the required cross-sectional area of the thin-layer fibrous filter element and the optimum height of the location of the overflow chutes for draining the separated liquid from the inertial-filtering to the drainage channels in order to avoid the secondary removal of droplets with the turbulent gas flow. As a result, the application rate of the separated liquid which falls from the filter element of the inertial-filtering separation channel to the drainage channels is obtained, as well as the dependence for the overflowed gutter of diverting the separated liquids from the inertial-filtering to the drainage channels is presented.

Vsevolod Sklabinskyi, Oleksandr Liaposhchenko, Ivan Pavlenko, Olha Lytvynenko, Maryna Demianenko

CFD Simulation of Ammonium Nitrate Melt in a Perforated Rotating Bucket

In this paper, a computational fluid dynamics (CFD) model was developed to study the influence of the flow pattern of ammonium nitrate melt on the jet emerging from the perforations located on the wall surface of the rotating bucket. The numerical simulations were carried out using ANSYS CFX software in which a three dimensional model closed via a k-ε turbulence model was adopted. To improve the performance of the bucket, design parameters such as a number of blades setting up in the bucket and selecting their geometrical shape were examined in depth. It was found that these parameters had a crucial impact on the velocity of the melt jet. While increasing the jet velocity, the probability of plugging and alteration of geometrical sizes of perforations decreases. This enables using the bucket for dispersing melts with solid impurities. The results of CFD simulation were applied for developing a modified rotating perforated bucket of the melt with nitrogen fertilizers, which has passed experimental and industrial tests.

Maksym Skydanenko, Vsevolod Sklabinskyi, Saad Saleh

Mathematical Model of Corrosive-Mechanic Wear Materials in Technological Medium of Food Industry

Using the thermodynamic methods of the irreversible process proved that the speed of corrosive-mechanical metals wear in the technological media of electrolytes of food industry depends on the linearly loads and speed of the slip and depends parabolically on the loss of strength of the materials by a corrosive-active medium. The influence of the electrode potential of metals in technological environments of food industries and the magnitude of their change in the friction of contacting surfaces of parts on the intensity of wear are determined. The methods of control over the process about corrosive-mechanical wear are pointed. The validation of a mathematical model of wear for adequacy was conducted in the technological medium of food industry. The methods of controlling the intensity of the process of corrosion-mechanical wear due to the strengthening of the friction pairs in the cathode or anode area, the selection of the composition of contact materials, and the inhibition of technological environments are proposed. The corrosion-mechanical wear of the surfaces in aggressive technological environments of food production are proven not to be regarded as a simple summary of mechanical and electrochemical factors.

Yuriy Sukhenko, Vladislav Sukhenko, Mikhailo Mushtruk, Alexander Litvinenko

Light and Heavy Pollutant Removal by Modified Swirl Sedimentation Tank – Design and Study

The paper shows the effect of volumetric flow rate of liquid and diameters of solid particles in the sedimentation tank for the water contaminated with sediment and oil substances on the effectiveness of the tank. The effect of liquid flow rate on liquid damming has been studied. It has been shown that the liquid damming in the tank increases with increasing a volumetric flow rate of liquid at the inlet. The determined value of the loss coefficient is 3.06. The effectiveness of sedimentation tank for heavy fraction increases with the diameter of solid particles. It has been shown that an increase in the liquid flow rate reduces the effectiveness of the tank, both for the heavy and the light fractions. The vortex sedimentation tank of the proposed construction allows for the simultaneous removal of the heavy and light fractions from water and their partial separation.

Sylwia Włodarczak, Marek Ochowiak, Małgorzata Markowska, Szymon Woziwodzki, Magdalena Matuszak

Investigation of Hydrodynamics During Continuous Vibroextraction in a Liquid–Solid Body System

Results of investigations of the hydrodynamics of flows in a counterflow continuous column-type vibroextractor for a liquid–solid body system and their generalization in the form of a mathematical description are presented. An equation for calculating the distance of propagation of pulsating turbulent jets formed by original vibrating transporting elements in a nonflowing medium, which can be taken as a scale factor in modeling the process, has been obtained. An analysis has been carried out, and a mathematical model of the structure of real flows in the vibroextractor has been developed on the basis of a combined model for the conditions of pulse perturbation of the hydrodynamic system of the apparatus. The mathematical description of the structure of flows can be taken as a base for the solution of optimization problems. We propose a new design of a vibratory extractor with a transporter for industry, which provides efficient separation of phases under the conditions of counterflow vibratory extraction of desired components from vegetable raw materials.

Vladimir Zavialov, Taras Misyura, Nataliya Popova, Yuliya Zaporozhets, Vadim Dekanskiy

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