Naukovij žurnal «Tehnìka ta energetika»

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ISSN / EISSN : 2663-1334 / 2663-1342
Total articles ≅ 190
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S. I. Bondariev, National University of Life and Environmental Sciences of Ukraine
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 129-133; https://doi.org/10.31548/machenergy2020.03.129

Abstract:
Transport processes research are closely related to the economic and operational performance of road transport. During planning road transportation, the most important factor is the transport services cost. Known fact that most of the transportation costs are car fuel. The share of car fuel in the transport tariff cost can be 25-50% (depending on the working conditions of vehicles). Therefore, research that is associated with improving the vehicles efficiency by reducing variable costs is appropriate and relevant. The article presents the results of research on the planning of transport processes in the road transport performance in international road transport for the return flight and calculating methods the demand for the amount of fuel purchased in different countries with different prices. The author presents the results of theoretical and experimental research the adequacy of the mathematical model (methodology). The specified mathematical model consists in substantiation of a technique of calculation of quantity of car fuel, definition of the variable factors influencing volumes of fuel expenses, calculation of correction factors (total) received on the basis of technical and operational indicators of vehicles and the influencing factors connected with features of road transport work. . The second part of the research contains the results of the development of an algorithm development to calculate the total cost of automotive fuel, which was purchased at different prices in several countries. Thus, the main purpose of research is the task of substantiating the algorithm (mathematical model – methodology) for determining fuel costs by the criterion of the highest use of fuel in countries at the lowest prices.
O. V. Kozachenko, Kharkiv Petro Vasylenko National Technical University of Agriculture, K. V. Siedykh, Kharkiv National Agrarian University named after V. V. Dokuchayev
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 31-39; https://doi.org/10.31548/machenergy2020.03.031

Abstract:
The article presents the results of theoretical studies of the dynamic model of the process of deformation of the elastic rack of a disk tool of arbitrary shape, a system of differential equations in general and developed the corresponding program code in Mathematica software package. Taking the form of an elastic discus disk for an Archimedean spiral, when the functions of its boundaries are given in polar coordinates, where the parameters of the geometric shape a (spiral pitch), b (spiral displacement along the radial coordinate), h (elastic column thickness) are determined by its equivalent physical a mathematical model in the form of a rigid mathematical pendulum of length l, to the load of which are attached two springs along the axes Ox and Oz with stiffness coefficients kx and kz, respectively, which deflect it by an angle φ. The dependences of the stiffness coefficients kx and kz, the length l and the angle φ of the equivalent physicomathematical model of the elastic stand of the disc with the parameters of the geometric shape a=0.8 m, b=0 m, h=0.01 m on the values of Fex and Fez, acting on the free end of the rack along the axes Ox and Oz.
O. M. Zagurskiy, T. S. Zhurakovska
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 55-60; https://doi.org/10.31548/machenergy2020.03.055

Abstract:
Negative changes in the environment, leading to public pressure and environmental legislation require fundamental changes in the industrial practice of business. Survey of the environment in 22 countries found that: in half of the countries surveyed, the environment is considered to be one of the three most serious problems of concern to society. In most countries, the overwhelming number of citizens surveyed indicated that the state of the environment had an impact on their health, and an even larger proportion stated that the environment had an impact on the health of their children. The article deals with the problem of increasing the level of environmental friendliness of transportation in supply chains. With the modern requirements in the integrated green supply chain, the reduction of the harmful impact of production and logistics activities on nature should be considered at all stages of the technological cycle of product development and its promotion through the supply chain. It is determined that the key technologies for reducing the anthropogenic impact on the environment are the optimization of transport processes due to the reduction of distance during transportation at all stages of the supply chain; the increase in the use of local resources (reducing fuel costs and harmful emissions); the use of modern environmentally friendly energy-efficient vehicles. The basic principles and approaches of the consolidated cargo transportation model have been substantiated, which balances environmental and economic problems and their testing has been carried out in the supply chain of the Epicenter hypermarket chain
K. V. Borak, Zhytomyr Agrotechnical College
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 67-73; https://doi.org/10.31548/machenergy2020.03.067

Abstract:
On the basis of a system analysis of methods of total running time and wear resistance improvement of tillage tools it has been found that in 90% of cases their improvement is achieved by technological methods. In its turn, it requires the use of expensive hardening materials that results in production cost increase of final output. The solution to a problem cannot be based on using one group of methods, it requires a complex approach when using a range of available groups of methods. Correspondingly, the purpose of the research is to identify experimentally some feasible methods of total running time and wear resistance improvement of tillage tools with due regards to soil and climatic conditions of their operation. On the basis of soil and climatic conditions of tillage tools operation, the research identifies experimentally some operational, constructional and technological methods of wear resistance improvement of share and disk tools. The research results have been introduced at the agrarian enterprises of Zhytomyr oblast.
В. С. Хмельовський, National University of Life and Environmental Sciences of Ukraine
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 89-93; https://doi.org/10.31548/machenergy2020.03.089

Abstract:
The issues of implementation of technological processes of preparation and distribution of feed mixture, according to the schedule of technological operations of the livestock complex are considered. The processes of preparation and distribution of the feed mixture are largely influenced by natural and climatic conditions, and accordingly, the daily performance of technological operations has certain deviations in time according to the routine of the livestock complex. One of the features of the processes of preparation and distribution of the feed mixture is the movement of the feed preparation unit between the feed storages under various weather conditions that affect the speed of the unit. Based on the results of evaluating the delay in the execution of technological operations in the preparation and distribution of the feed mixture, using the method of mathematical modeling, the influence on the productivity of animals was determined, justified optimal, from the point of view of zootechnical requirements, delay intervals in the execution of operations in which animals do not lose productivity and ways of their compensation are proposed when performing technological processes. The results of literary studies indicate that a delay in the distribution of the feed mixture for more than 10 minutes leads to a rapid increase in the loss of milk production of animals, and the time for their recovery is about 4-5 days. On the basis of the studies carried out, it has been proved that it is possible to compensate for the delays in the execution of technological operations of the preparation and distribution of the feed mixture by the time that falls on the mixing of the feed components, and can be partially or completely reduced, (provided that transportation operations are performed simultaneously, from the last load of the feed component and mixing). The calculation of the maximum deviation in the execution of the processes of preparation and distribution of the feed mixture, carried out by the method of mathematical modeling, determined that the maximum duration of the delay, taking into account the time to which the animals do not react, can be 22-27% of the preparation time of the feed mixture.
V. S. Loveikin, National University of Life and Environmental Sciences of Ukraine, Yu. O. Romasevych, D. I. Mushtyn
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 101-108; https://doi.org/10.31548/machenergy2020.03.101

Abstract:
The article analyzes the quality of the implementation of the optimal laws of simultaneous motion of the tower crane slewing and the trolley movement mechanisms. The estimation was carried out according to the maximum and root-mean-square values of the deviations of the theoretical and experimental characteristics. In addition, the graphical dependencies have been built. The data were estimated according to the characteristics of the speed of movement of the trolley and the rotation of the crane, as well as the angles of deflection of the load in the normal and tangential directions in the modes of acceleration and deceleration of the mechanisms. As a result of the analysis, it was found that the main reasons for the deviation of theoretical and experimental data on the characteristics under study are that the stiffness characteristics of the crane metal structure have not been taken into account, the parameters of the mechanisms are not accurately determined, and there are no feedbacks on the control characteristics (the speed of rotation of the crane and the speed of trolley movement). However, when implementing optimal control by means of a frequencycontrolled drive, pendulum oscillations of the load in the normal and tangential planes are eliminated. In addition, the analysis of the current loads of the drives of mechanisms and the acceleration of the crane boom was carried out. It was found that with optimal control, there is a significant decrease in the maximum values of acceleration, which means a decrease in dynamic loads on the crane metal structure. Also, the maximum currents in the motor windings of the crane mechanisms have been reduced, which, of course, will have a positive effect on the energy efficiency of the crane mechanisms.
V. O. Hryshchenko
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 23-29; https://doi.org/10.31548/machenergy2020.03.023

Abstract:
Storing grain quality materials in post harvest handling and storage is largely dependent on correctly implemented the drying process. In agricultural production mainly use costly convection dryer. The main share of wasteful energy consumption accounts for heat drying agent, some heat is lost to the environment through the working surface of the dryers and spent coolant. Ways to reduce these energy costs is to reduce the amount of drying agent in the process to the level necessary to absorb and remove moisture from the dryer and the working volume of the principles of targeted "delivery" of energy to vysushuyemoho material. Last principles successfully implemented using contactless energy supply of electromagnetic fields in a material exposure by microwave or infrared radiation. The article deals with the theoretical background processes of drying material in cyclic mode with infrared heating and high frequency electromagnetic field. The equations change over time settings grain material by heating using high frequency electromagnetic field or infrared light and ventilation in the grain does not allow heated air drying cycle count process. The algorithm calculating the overall process of drying cycle to determine rational modes of the process, providing minimize energy costs. The article deals with the theoretical background processes of drying material in cyclic mode with infrared heating and high frequency electromagnetic field. The equations change over time settings grain material by heating using high frequency electromagnetic field or infrared light and ventilation in the grain does not allow heated air drying cycle count process. The algorithm calculating the overall process of drying cycle to determine rational modes of the process, providing minimize energy costs. The article deals with the theoretical background processes of drying material in cyclic mode with infrared heating and high frequency electromagnetic field. The equations change over time settings grain material by heating using high frequency electromagnetic field or infrared light and ventilation in the grain does not allow heated air drying cycle count process. The algorithm calculating the overall process of drying cycle to determine rational modes of the process, providing minimize energy costs. The equations change over time settings grain material by heating using high frequency electromagnetic field or infrared light and ventilation in the grain does not allow heated air drying cycle count process. The algorithm calculating the overall process of drying cycle to determine rational modes of the process, providing minimize energy costs. The equations change over time settings grain material by heating using high frequency electromagnetic field or infrared light and ventilation in the grain does not allow heated air drying cycle count process. The algorithm calculating the overall process of drying cycle to determine rational modes of the process, providing minimize energy costs.
D. A. Derevianko, Polissya National University, V. M. Polishchuk, O. D. Derevianko, National University of Life and Environmental Sciences of Ukraine
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 49-54; https://doi.org/10.31548/machenergy2020.03.049

Abstract:
Theoretical calculations and experimental studies show that during the technological process of transporting seeds by technical means, in particular ladle conveyors, macro- and especially microtrauma of grains occurs, which affects a decrease in quality indicators. Analysis of the studies shows that the structural parameters of the working bodies, the biological and physico-mechanical properties of the kernels, as well as the material for the manufacture or coating of the working elements, affect the trauma and quality of the seeds. Experimental data showed that microtrauma of winter wheat grains before transportation was in the range of 22,9- 23,5%, and after completion of the transportation process was 45,3-46,4%, that is, doubled. Further studies to improve the quality of seeds of grain crops, reduce the harmful effects of microorganisms on caryopsis and reduce macro- and microtrauma should be carried out in the relationship and the complex of biological and physico-mechanical features of the entire technological process.
Ye. G. Aftandiliants, National University of Life and Environmental Sciences of Ukraine
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 81-87; https://doi.org/10.31548/machenergy2020.03.081

Abstract:
It is based of process analysis of structural steel operation at elevated temperatures and stresses, it is established that their workability depends with the chemical composition of steels and operation stress, time, temperature. The heat-resistant structural steels alloying is aimed for reducing the intensity of softening processes, that is, the redistribution of the alloying elements between the solid solution and the separation phases, their coagulation and changes of the crystal structure defects. The results of the study of chemical composition effect, temperature, stress and operation time on the creep and durability of structural steels are presented in the article. Analytical dependences of the relative elongation in the creep process and time at which the destruction of the chemical composition of heat-resistant structural steels and such operational factors as temperature, stress and holding are calculated. It is established that the creep and durability of heat-resistant structural steels, in the experiment conditions, are determined by their chemical composition in quantity 61–64 %, temperature 7–18 %, holding time 11 %, stress state 18–21 %. Nitrogen and vanadium alloying have been shown to more effectively reduce the softening degree heat-resistant steel during creep process than the molybdenum alloy, since the coagulation process of carbides and nitrides in steels with nitrogen and vanadium receives less development than carbides in steels alloyed by molybdenum.
O. M. Zagurskiy, National University of Life and Environmental Sciences of Ukraine
Naukovij žurnal «Tehnìka ta energetika», Volume 11, pp 95-100; https://doi.org/10.31548/machenergy2020.03.095

Abstract:
In the present circumstances, increasing of the motor transport enterprises efficiency contributes to the growth of its own competitiveness, has a significant influence on the competitiveness of their counterparties and the general level of competitiveness of the country's economy too. Therefore, the issue of improving the methods of evaluation of motor transport enterprises efficiency and search for new approaches of measuring of their investment potential is relevant. The purpose of the article is to develop economic and mathematical methods for evaluation of motor transport enterprise investment potential. The approach to generalizing the system of indicators for evaluation of motor transport enterprise investment potential was developed in the article. Procedure for conducting an investment potential analysis is based on the calculation of qualitative and quantitative indicators of the efficiency of motor transport enterprises activity. Function of desirable is the main tool of this methodological approach, that is complemented by the integrated coefficient calculation and using an objective-structural approach to reduce the subjectivity of non-formalized indicators. The proposed integrated indicator of the motor transport enterprise investment potential level gives an opportunity to comprehensively approach to an activity efficiency and enterprise management evaluation and identify the individual processes that need to be improved. Realization of the developed measures gives an opportunity to increase the overall efficiency of a motor transport enterprise management and increase its investment attractiveness for potential investors.
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