卷 34, 编号 2 (2024)
- 年: 2024
- ##issue.datePublished##: 28.06.2024
- 文章: 9
- URL: https://journals.rcsi.science/2658-4123/issue/view/16756
完整期次
Technologies, Machinery and Equipment
Probing alternative fuel compositions to determine electrical parameters
摘要
Introduction. In this paper attention is paid to the study of electrical parameters of fifteen compositions of alternative fuels. The task of developing non-contact methods of fuel composition analysis is relevant.
Aim of the Study. The study is aimed at obtaining dielectric constant data of alternative fuels for further search of the relationship with combustion process.
Materials and Methods. For the study there was used a capacitor consisting of two 175x102 mm aluminum plates and a Sinometex ZT-Y multimeter.
Results. When comparing the dielectric constant values of all presented alternative fuel compositions, there is found the dependence between the minimum and maximum content of added alcohol and vegetable oils in the mixture. This dependence manifests itself in the nature of dielectric constant values correlating with the capacitor electric capacity, if there is the mixture between the plates. It is observed for all three hydrocarbons added to the mixture: ethanol, rapeseed and colza oils. For example, the dielectric permittivity increases throughout the range from 10 to 50% of the added ethanol, rapeseed and colza oils, reaching the values from Ɛ =3.05 to 45.31; from Ɛ = 2.35 to 2.72; from Ɛ = 2.33 up to 2.8, respectively.
Discussion and Conclusion. The analysis of the dielectric constant values of various alternative fuel compositions shows that when the content of alcohol and vegetable oils in the mixture increases from 10 to 50%, the dielectric constant increases. And this is true for all three hydrocarbons: ethanol, rapeseed and colza oils.
178-190
Modeling of the producing concentrated compound feed when changing the compound feed machinery
摘要
Introduction. For small farms, an urgent task is to adapt standard compound feed machinery for producing the specified local feeds. It is necessary to use sunflower seeds for producing oil and fat sunflower meal for cattle. There are no universal presses suitable for producing sunflower meal. The process of crushing sunflower meal also causes difficulties. Therefore, we need a set of machines for this operation.
Aim of the Study. The article is aimed at developing a mathematical model for producing sunflower meal on the field plot and feed concentrates with the use of the compound feed machinery, and for determining the optimal field plot and machinery with minimal technical and economic indicators.
Materials and Methods. The developed algorithm in view of the mathematical model is implemented in the Microsoft Excel 2016 program. The results and calculations for the choice of rational option of machinery for producing sunflower meal on a field plot are presented in the text of the article. Technical and economic indicators and costs of the workshop and its operation are calculated according to the recommendations of Doctor of technical sciences, Professor V. V. Konovalov, but taking into account the expressions obtained for technological calculation.
Results. A mathematical model for producing concentrated compound feed is developed. The calculations carried out for the choice of a rational option of the field plot and the compound feed machinery showed the schemes of machines that meet the objectives of the study.
Discussion and Conclusion. For the conditions under consideration, an effective option among the presented field plots, from an economic point of view, is the field plot and compound feed machinery presented at the scheme 1 (table 1). Technological calculation of the sunflower meal production plot and the compound feed machinery was carried out based on the developed algorithm in view of the mathematical model for producing concentrated compound feed and the program for its implementation, their technical and economic indicators, and the costs of the workshop and its operation were calculated, and the rational option of the field plot and the compound feed machinery were selected. The economic effect of the selected field plot and compound feed machine was achieved by reducing annual operating and other direct costs, reduced costs.
191-212
Agricultural Engineering
Justification of optimal operating parameters of the field cultivator tool through determining traction resistance
摘要
Introduction. The technological operation of soil tillage is an energy-intensive preparatory operation. The traction resistance of tillage units has a direct impact on this indicator.
Aim of the Study. The study is aimed at searching optimal operating parameters for the field cultivator tool through determining the traction resistance created by this tool.
Materials and Methods. The study was carried out in the field on an experimental facility using a full factorial experiment technique with a working model based on a three-level design.
Results. Through the regression analysis of experimental data, there was obtained a mathematical model that allows determining the optimal operating parameters for the field cultivator tool when performing a technological operation of soil tillage.
Discussion and Conclusion. While calculating, it was found that the lowest traction resistance PТ = 0,72 kN created by the tool is for the following values: tillage depth h = 4 cm, crumbling angle of the left-hand and right-hand flat-cutting wings f = 0° and the speed of the tillage unit v = 2,61 m/s. As the optimal operating parameters for a field cultivator tool, determined using the obtained mathematical model, it is recommended to use the crumbling angle of the left-hand and right-hand flat-cutting wings of the working body f = 0°, and the speed of the tillage unit v = 2,91 m/s. Taking into account the recommended optimal operating parameters of the tool, it is possible to calculate the value of the traction resistance index at different tillage depths. The traction resistance will change within the range of 0.79–1.81 kN, when the soil tillage depth changes from 4 to 12 cm. The resulting mathematical model of the traction resistance created by the tool will allow a more accurate approach to the issue of designing agricultural machines.
213-228
Justification of dual-level opener parameters in digital twin by the discrete element method
摘要
Introduction. The discrete element method is the most promising method for modeling soil tillage. With the use of DEM modeling it is possible to create a digital twin for technological process of interaction of tools with soil, analyze the operation of tillage and seeding machines having various design and technological parameters, and predict energy and agrotechnical indicators of еtheir work. To improve the prediction accuracy, it is necessary to compare the obtained data with the results of field experiments.
Aim of the Study. The study is aimed at developing a digital twin of the tillage bin through using the discrete element method and optimizing the main design and technological parameters of the dual-level opener.
Materials and Methods. To simulate the process of the soil-opener interaction, there was used the discrete element method; the advanced Hertz‒Mindlin model was used as a contact model. For DEM modeling there is created a virtual tillage bin, which is filled with spherical particles of 10 mm diameter with the specified rheological parameters of the selected contact model. The main design factors for carrying out computer experiments in order to optimize them were the opener blade rake angle α and the furrow rake angle β. The opener traction resistance R was chosen as the output optimization parameter.
Results. Implementation of multifactor experiments on the digital twin of the soil bin in the Rocky DEM program allowed to optimize the design and technological parameters of the dual-level opener: bit inclination angle α = 75o, furrow former inclination angle β = 21o, vertical distance between the bit and furrow former Δa = 11‒14 mm.
Discussion and Conclusion. As a result of the modeling, it was found that the opener traction resistance increases in quadratic dependence on the opener operating speed and surface energy of the contact model.
229-243
Parameters and modes of a hydraulic mini seeder operation for small-seeded vegetable crops
摘要
Introduction. In the area of sowing with water and suspensions, there has been observed the trend of the development of hydroseeding lawn grass. The direction is less studied for sowing small seeds (germinated and sprouted) of vegetables. Existing works are mainly aimed at substinating the sowing of germinated seeds of watermelons, pumpkins, cucumbers and tobacco. At the same time, there are no studies for hydroseeding of carrot, parsley, dill, lettuce, tomatoes and celery seeds. Thus, theoretical research aimed at substantiating the method and technical solutions for sowing small-seeded crops in open and closed ground conditions are relevant. The problem is the lack of constructive-technological scheme of the tank for formation of sowing mixture of small-seeded crops, design and mode parameters of hydraulic mini seeder for sowing in drills to increase the efficiency of sowing.
Aim of the Study. The study is aimed at optimizing parameters and modes for operation of a hydraulic mini seeder for sowing in drills.
Materials and Methods. Theoretical studies of the process of homogenization of the seed mixture, power consumption during the operation of the reservoir for the formation of the seed mixture were carried out. Laboratory studies were carried out in Kuban State Agrarian University, field studies in private farms of Krymsky district of Krasnodar Krai.
Results. There have been jbtained the expressions describing the dependence of the value of the average circumferential velocity of the seed mixture flow and the power during the operation of the reservoir for the formation of seed mixture for various combinations of design and operating parameters. The analytical dependence describing the value of seed concentration in the carrier medium at a specified moment of time at a fixed point of the tank height is presented.
Discussion and Conclusion. Optimal parameters and modes for the operation of a universal hydroseeder for a seeding step are: agitator rotation frequency ‒ 92 min–1; crane opening value – 47%; seeder speed – 3.1 m/s at seeding step 20.5 mm; for seeding step variation coefficient: agitator rotation frequency ‒ 87 min–1; crane opening value – 56%; seeder speed – 2.7 m/s at seeding step variation 15%. The use of suspensions for hydroseeding vegetable crops is promising and should be developed.
244-264
Instruments and Methods of Experimental Physics
Identification of defects in products made from honeycomb composite materials using infrared scanning thermography
摘要
Introduction. Recently, sandwich-structured composite materials based on honeycomb core and strong thin shells have become widespread.
However, these materials are characterized by manufacturing and operational flaws such as “non-gluing” and “delamination” that is the breaking of the bonds between the shell and the honeycomb core that result in the deterioration in the mechanical, acoustic and thermal properties of the material.
Aim of the Study. The study is aimed at developing effective methods for detecting flaws in gluing shell with comb core in honeycomb polymer materials.
Materials and Methods. The article describes a method for detecting these flaws using scanning thermography with a linear heat source, based on the estimation and subsequent analysis of the distribution of local temperature field gradients on the product surface.
Results. The experiments were carried out on a model polymer specimen with an embedded artificial flaw; there were shown the main sources of emerging noise, control errors, and the ways to reduce their influence; a numerical method for assessing the accuracy of the flaw measurement method was proposed.
Discussion and Conclusion. Tests carried out on a control specimen showed that the proportion of errors in measuring a defect does not exceed 12%.
265-280
Optical photoluminescent properties of plant seeds when infected with mycopathogens
摘要
Introduction. Using digital technologies such as optical monitoring of grain quality will reduce losses of grain crops caused by infection with mycopathogens.
Aim of the Study. The study is aimed at investigating spectral characteristics, excitation parameters and luminescence of cereal seeds when infected with mycopathogens to determine informative spectral ranges and subsequent development of infection control methods.
Materials and Methods. In the study, there were used wheat and barley seeds inoculated with Fusarium graminearum, Alternaria alternata. Excitation and luminescence registration spectra were measured by a diffraction spectrofluorimeter CM 2203 in the range of 230–600 nm. Integral and statistical parameters of spectra were calculated with the use of Microcal Origin program.
Results. It was found that the spectral absorbency of seeds decreases when infected with mycopathogens. For wheat, the integral absorption parameters decrease more significantly when infected with alternaria, and for barley, on the contrary, a greater decrease occurs when infected with fusarium. In the area of 230–310 nm, new excitation maxima appear in infected seeds. When excited by radiation with a wavelength of λ = 284 nm, the spectral and integral characteristics and parameters of infected seeds exceed those for uninfected ones. When excited with 424 nm and 485 nm radiation, the number of disease-free seeds of both wheat and barley exceeds the number of infected seeds.
Discussion and Conclusion. The changes in excitation and photoluminescence spectra can be explained by the substitution of polysaccharides and proteins during mycoculture uptake and modification. To objectively monitor the mycopathogen infestation of seeds, it is advisable to use a photoluminescence range of 290–310 nm when excited by radiation of about 284 nm. To determine if the infection caused with fusarium or alternariasis, photoluminescence monitoring should be used in the range of 380–410 nm.
281-294
Electrical Technologies and Equipment
Computer simulation of a digital system of automatic light control
摘要
Introduction. In the poultry industry, the use of local LED lighting systems with changeable light and correlated color temperature of the luminaire optical radiation during the photoperiod is promising. To maintain light intensity accurately at a specified level, the use of an automatic control system (ACS) of lighting is required.
Aim of the Study. The study at aimed at determining the parameters for the PI controller of the digital ACS of lighting in all-age cages, providing the required quality indicators of the regulatory process.
Materials and Methods. For the study there were used the elements of mathematical statistics, experimental research design theory, correlation and regression analysis, automatic control theory and computer simulation. Real experiments were carried out on a laboratory sample of a digital dynamic local lighting system. Computer simulation was performed in the SimInTech program.
Results. A computer model for a digital ACS of lighting has been developed. The tunings of the PI controller were calculated using the CHR, VTI, and Kopelovich methods. A comparative estimation of the control process quality was carried out using graphs of transient processes obtained by computer simulation. The reliability of the results of computer simulation of ACS lighting has been confirmed experimentally.
Discussion and Conclusion. High regulator performance indicators for the digital ACS of lighting were ensured by a PI controller with kP = 14.027∙10−3 and TI = 145.72 ms calculated using the Kopelovitch method. A comparative assessment of transient processes in a real ACS and in a computer model of this system allows concluding that the developed model is highly accurate and the choice of simulation parameters in the SimInTech program is correct. It has been experimentally established that the required quality of the control process of ACS is ensured for a wide range of specified lighting: from 1 to 25 lux.
295-317
Justification of the microwave unit parameters for removing fat from the bones of meat-producing animals
摘要
Introduction. The existing methods of removing fat from the bones of meat-producing animals are low-efficient and require high operating costs. To solve this problem, a unit with an ultra-high-frequency energy supply to the resonator is proposed. In this unit the crushed raw materials are subjected to thermomechanical action.
Aim of the Study. The aim of the study is to increase the efficiency of removing fat from the bones of meat-producing animals while preserving the product feed value in a continuous-flow process microwave unit with a coaxial resonator without a shielding housing by providing a high electric field strength and thermomechanical effect on the raw materials.
Materials and Methods. Three-dimensional electromagnetic modeling of electromagnetic field distribution processes in a coaxial resonator was carried out in the CST Microwave Studio, Computer Aided Design (CAD) and Computer Aided Engineering (CAE).
Results. The ultrahigh frequency unit contains a non-ferromagnetic truncated cone, inside which an electrically driven whip rotor with a non-ferromagnetic shaft is coaxially located, forming a coaxial resonator with a conical annular space. Fluoroplastic hubs are fixed to the rotor shaft with a height shift, to which corundum bilas are attached in pairs on both sides. A shell of a truncated cone coated with an abrasive material is coaxially attached to the inner shell of a non-ferromagnetic truncated cone. The dynamics of heating at different specific capacities of the microwave generator is determined taking into account the initial parameters of the crushed bone and fat raw materials.
Discussion and Conclusion. The results of studying the electrodynamic parameters of the resonator indicate that the electric field strength 2–5 kV/cm is sufficient to reduce bacterial contamination of the product. An effective mode for removing fat from bone raw materials is when the generator specific power is 0.71 kW/kg, duration of exposure to an ultrahigh frequency electromagnetic field is 6.55 min (when loading the resonator 9.3 kg), productivity is 85 kg/h, energy consumption of is 0.141 kWh/kg and heating temperature is 90–100 оС.
318-335