scholarly journals Justification of the parameters of the stable course in depth at vibration exposure of the working body to the soil

Author(s):  
L.F. Babitsky ◽  
◽  
V.A. Kuklin ◽  

The aim of the research is to substantiate the parameters of the stable stroke along the depth of the vibrating tillage working bodies on spring struts. The article proposes an elastic-viscous rheological model of the soil and provides a theoretical justification for the parameters of the stable course along the depth of the vibrating working bodies on spring struts. The resulting expression includes agrotechnological and structural parameters, as well as physical and mechanical properties of the soil.

2018 ◽  
Vol 41 (1) ◽  
pp. 27-33
Author(s):  
N.O. Sharkova ◽  
E.К. Zhukotskyi ◽  
Т.Y. Тurchyna ◽  
H.V. Dekusha ◽  
A.A. Makarenko

The use of discrete-pulse energy input (DPEI) mechanisms in various industries has become a reliable tool for the intensification of heat and mass transfer processes in various technological lines and reduction of specific energy consumption. The study of structural transformations in heterogeneous systems under influence of mechanisms of DPEI opens up new possibilities for their use as evidenced by this article. Under certain conditions it is possible to prepare a mushroom suspension with specified characteristics for drying and enhance medicinal properties of the obtained powder product while retaining all valuable components of feedstock. The article presents the results of research of DPEI-processing effect of the shiitake mushroom fruit body on the on physical and mechanical properties and structural characteristics of the mushroom suspension. The influence of hydro module, temperature of the suspension and the layout of the working bodies of the rotor-pulse apparatus (RPA) on its dynamic viscosity was studied and the possibility of reducing viscosity by 2-3 times is shown.  An analysis of mushroom suspension microstructure has showed that with a certain layout of the working bodies of the RPA it is possible to control the degree of dispersion of particles and change the spatial structure of the aggregates in the volume of the dispersion medium. It is determined that self-organization of spatial aggregates from individual hyphae in such suspensions occurs over time. Moreover, the smaller the size of hyphae (≤ 25 microns after the RPA of the first version of the arrangement: rotor-stator-rotor) are, the larger the size of the spatial aggregates are formed. After the RPA with the second layout option, the fragments of hyphae had sizes ≥ 50 μm, but the dimensions of the spatial aggregates were three times smaller. It is found that after three times passing of the mushroom suspension through the RPA and its subsequent treatment in the cavitation device, the dynamic viscosity of the suspension is reduced by 20%. Confirmation of the the effectiveness of the DPEI-mechanisms in obtaining mushroom suspension is that due to the hydromechanical destruction of the polysaccharide structures of the chitin-glucan complex of the shiitake mushroom the content of the bioavailable complex of water-soluble oncostatic and immunoregulatory polysaccharides in the powder obtained by drying the mushroom suspension in an experimental spray dryer increased 6 times. References 13, figures 6.


2019 ◽  
Vol 23 (3) ◽  
pp. 101-114
Author(s):  
Katarzyna Szwedziak ◽  
Igor Stadnyk ◽  
Sergey Golyachuk ◽  
Żaneta Grzywacz

AbstractIt is justified thatproblems related to the changes in structural and mechanical properties of plastic material and influence of structural elements of equipment and modes of implementation of the for-mation process on them are considered detail, taking into account empirical data, theoretical dependencies and results of physical experiments. It was established that during the mechanical influence of rollers with grooves on a structured dispersion plastic material in the node of injection of the molding machine, internal shear, and shearing deformation have a preponderant value. Accordingly, the productivity of machines is determined mainly by the structural parameters of the working bodies geometry, kinematics, and contact area. It is shown that increasing the pressure in the plastic material causes a decrease in its volume, but the relationship between pressure and volume has a nonlinear character. It has been established that regardless the variety of flour from which the plastic material was prepared for bagels, its moisture content and the duration of fermentation reduced viscosity of the effective plastic material along with the increase of the shear stress. The paper describes the refined rheological model of the Bingham body deformation, which develops instantaneously, and the velocity of the common elastic deformation in the dough is a simultaneous function of stresses and temperatures, which are close to exponential ones.


2020 ◽  
pp. 72-75
Author(s):  
Alexander Gennadievich Aksenov ◽  
Aleksey Viktorovich Sibirev

The aim of the research was to determine the size-mass and physico-mechanical properties of bulbs and heaves of seed onion of the Stuttgart Riesen variety during the selection period. The results of studies of the size-mass characteristics of bulbs and roll onion sets of the Stuttgart Riesen variety from the standpoint of creating the working bodies of machines for its cultivation and harvesting are presented. The results of previous studies of onion sets of other varieties are considered. The technique and equipment used in the research are described. The results of the studies are presented in the form of distribution histograms, the analysis of the studies was carried out by the method of variation statistics. Object of study: bulbs and roll onion sets of the Stuttgart Riesen variety. It is established that the value of the onion set form index lies in the range of 0.,82- 1,10. An analysis of the results shows that more than 90% of the bulbs have a rounded shape, approaching the shape of a sphere, the rest are flat-rounded. The main values of the width of the onion-set roll are in the range 53.,0 65,0 cm, with an average value of 59 cm, in addition, we can conclude that there is no large change in thickness in the cross section of the roll, while the average value of the thickness of the roll (left , middle, right) is within 5.4; 6.7; 5.2 cm with an average value of 6.4 cm. The average distance between the onion set rolls during the selection period is 113.4 cm, the maximum is 121 cm, and the minimum is 111.2 cm. The mass of a heap of 1 running meter of onion set roll characterizes the density of the onion set roll is 12.82 kg. However, the minimum and maximum values of this indicator have a wide range of variation from 12.0 to 15.0 kg.


2021 ◽  
Vol 295 (2) ◽  
pp. 271-274
Author(s):  
V. SHCHERBAN ◽  
◽  
A. PETKO ◽  
O. KOLISKO ◽  
Y. SHCHERBAN ◽  
...  

Improving the process of knitting fabrics from Kevlar complex threads on flat knitting machines is to create the minimum necessary tension in the area of formation of the knitted fabric. To ensure this, it is necessary to determine the change in relative tension in the refueling zones of Kevlar complex threads on flat knitting machines. These zones are formed by arranging the thread guides, tension compensation devices, tension devices and thread break control devices in the working area of the supply system to form a spatial filling line for each specific knitting machine. This complex task for flat knitting machines should be based on the use of specially designed computer programs. Given the specifics of processing Kevlar complex threads on flat knitting machines, when determining the relative tension in each zone, it is necessary to use a recursion algorithm, when the output tension of Kevlar complex threads from the previous zone will be the input for the next zone. When determining the tension of Kevlar complex threads, their interaction with the guides of Kevlar complex threads, tension compensation devices, tension devices and devices for controlling the breakage of Kevlar complex threads, it is necessary to take into account the value of Kevlar complex thread diameter, its physical and mechanical properties, deformation, deformation the coefficient of bending stiffness when determining the actual angle of coverage of the guide surface. Ensuring the minimum necessary tension in the area of formation of the knitted fabric will allow to obtain the parameters of the loop structure of property and tactical equipment of servicemen capable of protecting the human body from fire, cold, cutting, barbed weapons, shock and shotgun impact. Minimizing the tension in each zone of the line of Kevlar complex threads on flat knitting machines will reduce the probability of breakage, which is important for improving knitting processes from the standpoint of improving the productivity of flat knitting machines and product quality. Mathematical support of a computer program requires the development of models of thread guides, tension compensation devices, tension devices and thread break control devices, taking into account the real physical and mechanical properties of Kevlar complex threads and real geometric and structural parameters of structural elements of the feed system.


Author(s):  
Д.В. ЕВТЕХОВ ◽  
Р.В. БЕЗНОСЮК ◽  
С.Т. КОДИРОВ ◽  
Г.К. РЕМБАЛОВИЧ ◽  
Н.С. ЖБАНОВ

Проблема и цель. В процессе уборки картофеля меняются почвенно-климатические условия, урожайность, свойства убираемых клубней и поэтому уборочный комплекс должен гибко реагировать на эти изменения. Это предполагает не только своевременную настройку рабочих органов, но и более широкие возможности современных картофелеуборочных машин. Цель – совершенствование картофелеуборочных машин на основе применения полимерных и композиционных материалов. Методология. Появление в бункере комбайна клубней с повреждениями, ушибами (потемнение мякоти) свидетельствует о значительных динамических нагрузках рабочих органов. Предлагаемый сепарирующий элеватор имеет гибкие композиционные прутки, которые взаимодействуют с обрезиненными роликами-интенсификаторами и при движении образуют волнообразную, постоянно меняющуюся поверхность. При поступлении картофельного вороха гибкие композиционные прутки прогибаются, причем чем больше масса поступающего картофельного вороха, тем больше величина прогиба прутков. При изменении почвенно-климатических условий значительная нагрузка приходится на органы выносной сепарации, поэтому увеличение производительности и снижение повреждений клубней является важной задачей. Для повышения эффективности работы продольной прямоточной пальчиковой горки был предложен многокулачковый встряхиватель с регулируемой частотой и амплитудой воздействия. Благодаря колебательным воздействиям полотна пальчиковой горки картофель приобретает дополнительную подвижность, что позволяет более полно использовать различия физико-механических свойств клубней и примесей. Результаты. Применение сепарирующего элеватора с композиционными прутками увеличило сепарирующую способность картофелекопателя на суглинке нормальной влажности (22 %) и снизило повреждения клубней на 2,6 %. Сравнительные показатели качества работы комбайна Grimme DR-1500, оборудованного модернизированной горкой с многокулачковым всряхивателем и серийного комбайна Grimme DR-1500 соответственно составили: полнота уборки – 97,3 % и 95,8 %; полнота выделения примесей – 94,1% и 86,8 %; процент повреждений клубней –2,47 % и 3,15 %. Заключение. Увеличение интенсивности сепарации на рабочих органах из композиционных и полимерных материалов позволяет увеличить производительность картофелеуборочных машин. Problem and purpose. In the process of harvesting potatoes, the soil and climatic conditions change, the yield properties of the harvested tubers, and therefore the harvesting complex must respond fexibly to these changes. This presupposes not only the timely adjustment of the working bodies, but also the wider possibilities of modern potato harvesters. The goal is to improve potato harvesters based on the use of polymer and composite materials. Methodology. The appearance of tubers with injuries in the bunker of the combine with bruises (darkening of the pulp) indicates signifcant dynamic loads of the working organs. The proposed separating elevator has fexible composite rods, which interact with rubberized intensifer rollers and, when moving, form a wavy, constantly changing surface. When the potato heap arrives, the fexible composite rods bend, and the greater the mass of the heap, the greater the defection. With a change in soil and climatic conditions, a signifcant load falls on the external separation organs, therefore, increasing productivity and reducing damage to tubers is an important task. To increase the efciency of the longitudinal direct-fow hedgehog slide, a multi-cam shaker with an adjustable frequency and amplitude of action was proposed. Owing to the vibrational efects of the hedgehog slider, the potato acquires additional mobility, which allows more full use of the diferences in the physical and mechanical properties of tubers and impurities. Results. The use of a separating elevator with composite rods increased the separating capacity of a potato digger on loam of normal moisture content (22%) and reduced damage to tubers by 2.6%. Comparative performance indicators of the Grimme DR-1500 combine equipped with a modernized slide with a multi-cam shaker and the Grimme DR-1500 serial combine, respectively, were: completeness of cleaning –97.3% and 95.8%; completeness of separation of impurities – 94.1% and 86.8%; percentage of damage to tubers –2.47% and 3.15%. Conclusion. An increase in the intensity of separation on working bodies made of composite and polymer materials allows increasing the productivity of potato harvesters.


2021 ◽  
Vol 251 ◽  
pp. 745-756
Author(s):  
Konstantin Fomin

When performing technological operations in the peat industry, various units with milling-type working bodies are used. They differ in design, layout, number and type of cutting elements, operating modes, and may have one or more working bodies. During operation, random forces and moments act on the cutters, which have a dramatically variable nature, which is associated with the periodic interaction of the knives with the peat deposit, its structural heterogeneity, variations in the milling depth, physical and mechanical properties of peat, the rotational speed of the cutter and the movement speed of the machine. In this case, significant dynamic loads arise in the structural elements, which leads to a decrease in their reliability, deterioration of the energy characteristics of the engine operation and technical and economic indicators of use. In the dynamic analysis of drive elements, when using machines with several working bodies, it is necessary to know both spectral and mutual spectral load densities.  For their calculation, expressions were obtained that take into account the physical and mechanical properties of peat, the operating modes of the unit and their probabilistic characteristics, as well as the design features of the working body. The expressions are obtained for the case when there are several working bodies with the same diameters and the number of knives in the cutting plane. In this case, the number of planes, width, type of cutting element and type of cutting (locked, semi-locked, etc.) may differ. As an example of using the developed approaches, the calculation of spectral and mutual spectral densities of moments on cutters and loads in the drive elements of the machine for surface-layer milling MTF-14 is presented.


2020 ◽  
Vol 20 (4) ◽  
pp. 449-460
Author(s):  
Špela Bezgovšek ◽  
Dunja Šajn Gorjanc ◽  
Boštjan Pulko ◽  
Stanislav Lenart

AbstractNonwoven geotextiles are often used in road construction as a separation layer. They consist of the web of fibers with different orientations. The orientation of fibers has an important influence on physical and mechanical properties of nonwoven geotextiles. The production of nonwoven geotextiles is cheaper in comparison to woven or knitted fabrics which can also be used as separation geotextiles. The purpose of this research was to study the influence of structural properties of nonwoven geotextiles, namely the diameter of fibers and mass and thickness of nonwoven geotextiles, on their mechanical and hydraulic properties. Six types of nonwoven geotextiles were used in the research. They were produced by the drylaid process (carded) using mechanical bonding technique and also with the combination of mechanical and thermal bonding technique. The research confirmed that the bonding technique and structural properties significantly influence the separation and filtration properties of nonwoven geotextiles, such as opening size and water permeability. It was also found that there are no significant differences in mechanical properties, such as viscoelastic properties and compression creep, between the samples in the dry and wet conditions.


Author(s):  
А. А. Дудніков ◽  
О. І. Біловод ◽  
А. Г. Пасюта

У статті розглядаються питання підвищення до-вговічності і надійності робочих органів ґрунтооб-робних машин у процесі їх відновлення (виготовлення)з використанням вібраційних коливань, що сприяютьінтенсифікації методів обробки, підвищенню рівнямеханізації та автоматизації багатьох трудоміст-ких технологій. Показано залежність інтенсивностівібраційного зміцнення від наступних факторів: ре-жиму обробки та фізико-механічних властивостейматеріалу оброблюваних деталей. Встановлено, щоосновними параметрами технологічного процесу віб-раційного зміцнення є збурювальна сила віброзбуджу-вача, амплітуда і частота коливань обробногоінструменту, швидкість і час обробки. The article discusses issues of increasing longevity and reliability of working bodies of tillers in the process of recovery (manufacturing) using vibrations that promote intensification processing methods, increase the level of mechanization and automation of many labor-intensive technologies. The dependence of the intensity of the vibration to strengthen the following factors: the mode of processing, physical and mechanical properties of the material machined parts. Found that the main process parameters of the vibration of hardening is the disturbing force exciter, the amplitude and frequency of oscillation of the machining tool, the speed and processing time.


2021 ◽  
Vol 285 ◽  
pp. 07003
Author(s):  
Vladimir I. Konovalov

Under the action of the working surface of the tillage unit, three mutually perpendicular stresses and corresponding deformations occur in the soil layer, which are characterized by different time functions. The finding of these functional relationships is the fundamental task of agricultural mechanics, with the help of which the process of soil crumbling with different physical and mechanical properties can be described in interaction with working bodies. The article presents an analysis of the results of studies of domestic and foreign scientists of the process of soil destruction in its interaction with working bodies. When considering the process of soil destruction from the point of view of stress theory, the Coulomb-Mohr theory of destruction is most often used. It is proposed to expand the consideration of the process of soil destruction by adding elements to the theory of strength that will describe the rate of change of the acting loads.


2021 ◽  
Vol 410 ◽  
pp. 444-449
Author(s):  
Oleg V. Kudryakov ◽  
Valery N. Varavka ◽  
Dmitriy S. Manturov

Comparative studies of wear resistance during dry friction of vacuum ion-plasma coatings of nitride systems TiAlN and CrAlSiN are carried out. The structural parameters, coating thickness, and physical and mechanical properties were chosen as comparison parameters. A fundamental difference in the wear mechanisms of the coatings is demonstrated. In the TiAlN-system coatings develop an oxidative wear mechanism due to their insufficient heat resistance. The CrAlSiN-system coatings have maximum resistance to plastic deformation. And they are wear out according to the fatigue mechanism, which is typical for coatings with a high level of mechanical properties.


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