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Постійне посилання колекціїhttps://dspace.nuft.edu.ua/handle/123456789/7522
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Документ Prospects of using secondary energy resources(2019) Sokolenko, Anatoly; Shevchenko, Oleksandr; Vasylkivskyi, Kostyantyn; Stepanets, Oleg; Vinnichenko, InnaThe paper deals with the peculiarities of thermodynamic analysis of technological systems of food production with generation of secondary steam. System analysis is based on information about production, equipment operation, modern scientific achievements and modeling methods in chemical, physical, mathematical and other sciences. The information about applied energy and thermodynamic criteria, criteria of optimization of systems, list of sequence of actions on improvement of systems is given. Secondary energy resources of food industries are often represented by thermal energy of liquid media or secondary steam. Regeneration of the secondary steam allows, during its subsequent condensation, to return the heat potential of the steam to the media. This means that in the systems where the increase in the thermodynamic parameters of steam due to its compression, there is the use of Carno's return cycle. Such use occurs both in closed and open cycles. The description of the physical processes accompanying the work of the thermocompressors is subject to mathematical modeling based on the laws of conservation of energy, mass conservation and conservation of impulses. The assessment of the suitability for using secondary energy resources is based on exergy methods in order to determine the directions for their further improvement. For identical pressures in the mixing chamber, the efficiency of the actual compressor is higher than the ratio of the ejection coefficients of the real and ideal compressors, since internal irreversible losses along with the reduction of the ejection rate result in the increase of the specific exergy of the compressed flow.Документ Desaturation of cultural media in processes of anaerobic fermentation(2018) Shevchenko, Oleksandr; Sokolenko, Anatoly; Vasylkivskyi, Kostyantyn; Stepanets, OlegThe article deals with the analysis of transients in gas-liquid media with the self-synthesis of the gas phase. It is shown that the restriction of the mass transfer intensity in the culture media of the alcoholic and brewing industries is accompanied by the presence of transients in the state of saturation on СО2 . It is determined that the level of carbon dioxide accumulation increases due to physical and hydrostatic pressures and the latter one is determined by the geometrical parameters of fermentation vehicles, but the quantitative desaturation per unit volume of the medium does not depend on hydrostatic pressure. Quantitative desaturation of CO2 depends on the pressure differences in the ingenious volume. It is shown that the restoration of the sorption properties of the liquid phase is possible due to combinations of reduction and subsequent increase of physical pressure. The analytical dependences on determination of interconnections of physical parameters in digestible media are given.Документ Dynamics of springy systems of packaging lines for food products(2021) Sokolenko, Anatoly; Shevchenko, Oleksandr; Stepanets, Oleg; But, Serhiy; Shevchenko, AnastasiiaThe purpose of the study was to develop mathematical models and proposals for improving the technology and equipment for the supply of roll packaging materials. The analysis of features of systems for transportation of packing materials, dynamics of transient processes, research methods concerning movements of rolled materials, features of loadings in systems of cyclic action with springy elements are resulted in the article. It is shown that the modern theoretical basis of synthesis of technological machines on the basis of use of film rolled materials combines possibilities of the account of technological requirements, indicators of high productivity, neighborhood conditions, restriction of power parameters. Mathematical formalizations concerning the ratios of force factors in systems of transportation of loads of cyclic action at the levels of external force actions, generated friction forces, geometrical, kinematic and dynamic parameters were obtained. Mathematical models concerning runaway modes and estimation of stiffness of springy bonds, on the basis of film materials, methods of estimation of system parameters were offered. Synchronized combination of operations, the use of optimal laws of movement of working bodies, limitation of dynamic loads was carried to the positive directions of creating efficient technological machines and lines. It is proposed to determine the ratio of the run-out time of rolls of variable mass by the ratio of the squares of the initial and final radii. The solution of the problem of kinetic energy recovery in systems of periodic action is simultaneously connected with the restriction of the non-uniformity of the drive of machines.Документ Limitation of dynamic power parameters in transitional processes(2020) Sokolenko, Anatoly; Shevchenko, Oleksandr; Stepanets, Oleg; Romanchenko, Natalia; Shevchenko, AnastasiiaThe article is devoted to the analysis of the prospects of the complex use of the accumulated potential energy on the example of a mechanism for lifting, horizontal movement and loading of cargoes, for example, in transport container with limitation of dynamic loads. On the basis of the analysis of the peculiarities of the shock loads in two-mass systems, the possibility of using the rigidity of the springy pendant as a variable factor to achieve the given relations between static and dynamic loads during their course in the gravitational field was determined.