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Agricultural Engineering (Moscow)

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Vol 24, No 1 (2022)

FARM MACHINERY AND TECHNOLOGIES

4-11 177
Abstract

Within the "From Field to Counter" Strategy framework, the European Parliament calls for a review of the procedure for the admission of plant protection products (PPP) in the EU. The aim is to strengthen control over the PPP use and reduce their use. The development of energy- and resource-saving agrochemical technologies for the PPP use implies designing monodisperse spray devices for specific chemicals, specifying their consumption rates per unit area, and selecting compatible spray equipment and relevant agricultural technologies. The elaboration of spray technology requires a fundamentally new approach to its testing and determining the dispersed composition of spray droplets. To elaborate an innovative methodology for optimizing the operation of spraying devices based on the dispersive analysis of spray droplets, the authors have developed and manufactured a test bench that provides a representative aerosol sampling. Express analyzers of spraying quality have been developed, made in the form of cards with dimensions 90 by 40 mm or tape 40 mm wide and 3 m long, impregnated with a solution of potassium hexacyanoferrate (III) at a concentration of 5.. .7%. A computer program has been made for counting and ranking spray drops in a real-time mode. The article presents study results on the optimization of several parameters: the consumption rates of the products and the hydraulic medium, the density (concentration) of the power fluid droplets on the surface of the treatment object, the dispersed composition of the spray droplets (the droplet size, the degree of productivity polydispersity and the possibility of adjusting the technological process parameters). The developed experimental complex and the technology of experimental testing of spraying devices will facilitate comparative tests of spraying devices.

12-16 99
Abstract

The most critical problem in implementing any technology is to reduce labor costs while ensuring energy and resource conservation and simultaneously increasing the yield of cultivated crops and, consequently, reducing the cost of production. It has been established that saving technologies will reduce the number of unit runs through the field, preserve soil fertility, and minimize environmental pollution from fuel combustion products. The article presents a comprehensive assessment of the quality of technological operations of energy-resource-saving technologies for harvesting root crops and potatoes under high humidity conditions. The authors describe a coefficient of energy-resource saving that takes into account the direct costs of energy in the cultivation of crop products, including the costs of energy obtained from the liquid fuel combustion, direct costs of energy required for crop production, the energy of material and technical resources, and the energy of current assets. Numerical values of the comprehensive assessment indicator of energy-saving features of harvesting root crops and potatoes will describe the quality of technogenic impact of a set of machines used for harvesting vegetable crops. Application of the proposed method can help adequately estimate crop production's energy efficiency, taking into account the energy of direct and indirect costs.

17-22 81
Abstract

In the conditions of the Central Caucasus, hay harvesting on mountain slopes contributes to increasing livestock production. The authors propose using mining modification units for hay harvesting while applying table salt as a preservative to ensure better hay preservation. A set of hay harvesters aggregated with low-clearance tractors is porposed for hillside areas with a slope of up to 15°. The technical capabilities of the selected machines may optimize the harvesting time and reduce the cost of manual labor, ensure the most negligible loss of harvested feed, and increase its quality and preservation. The tests of this technology were carried out in the mountainous zone of the RSO-Alania (the Dargava basin, the site of SKNIIGPSH) at an altitude of 1540 m above sea level south-eastern exposure with a slope steepness of up to 15°. Experimental studies found that the content of fodder units in compressed hay increased by 32.1%, dry matter by 29.6%, crude protein by 17.3%, fat by 7.4%, fiber by 14.2%, sugar by 17.6%, and metabolic energy by 8.0%. The developed technology, as compared with manual harvesting, can reduce mechanical losses in more than 1.2 times, increase labor productivity in 4...5 times, and reduce the cleaning time in 3 times. At the same time, it was found that the consumption of harvested feed increased by 18.5%, which, together with its higher nutritional value, positively affected the physiological state of animals in the winter-stall period and led to an increase in milk yield by 11.7%

23-27 94
Abstract

Further development of organic agricultural production requires large volumes of organic fertilizers. Due to the sharp reduction in cattle, there is a lack of organic fertilizer in the form of animal waste. To solve this problem, eleven technological lines for processing natural organic raw materials in the form of peat, brown coal, and sapropel were developed, considering customers' technical requirements, and then delivered to some regions of Russia and Belarus. The authors analyzed the operation of these lines, and based on the study of the operation of individual units and assemblies, identified technical and technological problems. They studied and analyzed the possibilities of developing technological lines using modular equipment of machine-building organizations to process organic raw materials for making humic fertilizers. The research results made it possible to modernize individual technological lines using new innovative developments and modular equipment. Using a new design of a hydromechanical cleaner to clean the peat suspension before feeding it into the reactor increased the level of its purification to 97...98%. Reinforcement of the technological line with modular equipment (vibratory mill of MV-20 type) for grinding coal increased the quality of the reactor and reduced the ballast content after filtration to 1...3%. The dispersion of the fertilizer suspension supplied for filtration decreased to 50...70 microns. The introduction of the design of a new high-power dismembrator made it possible to reduce the production cycle time by 30 minutes. An additional installation of a hydromechanical cavitator increased the efficiency of extracting humic acids from organic raw materials. The microelement dosing system has been modernized to produce concentrated fertilizers up to 2.5 tons per shift. The research results have determined the expediency of further development of technological lines based on modular equipment.

28-34 88
Abstract

The digital transformation of agriculture and animal husbandry, in particular, involves, along with the development of sensors for the physiological state of cattle, the development of modular radio-technical digital devices for receiving and transmitting data. The developed module of the base station receives and transmits signals from bolus sensors located in the animal's rumen according to three main parameters (acidity, pH; temperature; motor activity). The base station module consists of two parts connected by cables: a Raspberry Pi 4 minicomputer, which acts as a control device, and an external data transmission module, which includes a transceiver for communication with bolus sensors mounted on animals and a GSM module for Internet access and communication with the server. The analysis of these basic parameters makes it possible to monitor the physiological state of animals using the developed software according to the corresponding correlation relationships. The authors have developed basic electrical and structural diagrams of the data transmission module as part of the base station. Also, the article presents a block diagram of the logical structure of the base station software. A test program has been developed that includes checking signal levels in various types of rooms using sensor simulators-boluses. Tests have shown that the signal level measured in the rooms under consideration at various heights does not exceed the minimum permissible signal level -70 dB. The experimental results have established a relatively uniform signal level distribution in the room and increased heterogeneity in the corners, which makes it possible to find a compromise between the system parameters and make the necessary analyses to predict the performance of the entire complex.

35-39 80
Abstract

The complexity of the separation process in potato harvesters implies the use of elevators with disc agitators. To increase the efficiency of soil sifting after the ploughshare, a disc agitator with rubber-coated fingers fixed on it is installed above the elevator. Due to its elasticity, the potato tubers are not damaged. The authors conducted a full-factor experiment on the influence of three factors on the completeness of separating a soil-tuber layer: an installation angle of fingers, the digger speed, and the disc agitator speed. The paper presents the levels and variation intervals of these factors. The authors obtained and analyzed the mathematical model equation reflecting the coded influence of significant factors on the separation completeness of a soil-tubular mass at potato harvesting based on the research results. The analysis of solutions to the mathematical model equation has established that at an angle of finger installation of 32.19° and speed of the potato digger of 0.203 m/s, the maximum separation completeness of a soil-tubular mass amounts to 90.8%. Experimental studies were conducted in 2020 during the potato harvesting season of the Romano variety in the farm "Sarvi Sad Khosili" (Kasansay district, Namangan region, the Republic of Uzbekistan). Due to the use of the disc agitator on potato harvesters, the number and degree of tuber damage decreased. The tubers moved with the soil layer, and this fact reduced the number of contacts between the tubers and the elevator bars

40-44 104
Abstract

Loading grain crops into various containers is not easy due to the impossibility of filling the entire required capacity, uneven distribution of material, restrictions on the container design, etc. The article considers the design of a screw-type conveyor-distributor used for uniform loading. The device consists of a screw placed in a casing. From below, along the entire length of the conveyor-distributor, there is a discharge hole of a particular geometric shape. The study task was to obtain the parameters of the screw-type conveyor-distributor, to determine their effect on the production parameters of the screw with known parameters of the loading capacity for ensuring uniform grain loading. In the course of a computer experiment, screws with diameters of 100, 160, 200, 250, 315, and 400 mm were examined. While their speed changed from 50 to 600 min-1 at intervals of 50 min-1, the screw length varied from 1 to 14 m in increments of 1 m. The results obtained revealed acceptable diameters and speeds of screw-type conveyor distributors depending on the dimensions of the loaded containers to ensure uniform distribution. Using the example of a rectangular warehouse with a size of 14 by 20 m, the authors determined the technical characteristics of a screw-type conveyor-distributor and determined the appropriate geometric shape of the screw casing hole to ensure uniform grain distribution.

45-48 74
Abstract

To make the agroengineering analysis of the drying process of sliced beets, it is necessary to know its moisture equilibrium. Due to the lack of the reference data for elevated temperatures at which drying of this material is carried out, the isotherms of moisture desorption were obtained and analyzed by the experimental static (desiccator) method for sliced beetroot at temperatures of 30, 40 and 50°C. The authors used saturated solutions of various mineral salts to get specific values of the relative air humidity in desiccators. They found the relative air humidity indicators in the space above them according to the well-known diagram of A. Schneider. The obtained moisture desorption isotherms are S-shaped, typical for capillary-porous colloidal materials, and they correspond to the fourth type of sorption isotherms according to the Brunauer classification. For the convenience of engineering analysis, they are described by the Henderson equation, which can be used to determine the values of the equilibrium moisture content of a material at various values of relative humidity and temperature. The authors have found values of the constants for this equation. A statistical assessment of the approximation reliability of the experimental data made by the Henderson equation has shown a satisfactory compliance of this equation with the experimental data. Since beetroot samples with high (natural) humidity were placed in desiccators when removing the equilibrium, the obtained isotherms are of the desorption type. They are exactly the type required to analyze the material drying process. The research results are applicable for analyzing the drying process for slicing beetroot and organizing the storage process.

49-54 76
Abstract

The use of quick-assembly (collapsible) pipelines is one of the effective ways of supplying water for periodic irrigation of agricultural land, especially when using highly worn-out existing irrigation systems. As a result of studies of the physicochemical properties of composite materials, the authors have proposed a linear element design of a collapsible pipeline, the principal technical solutions of which take into account the experience of operating domestic and foreign collapsible pipelines in irrigation systems. A feature of the proposed linear element is the one-piece construction of a pipe made of composite material without welds and joints with rigidly connected reinforcing metal nodes located in areas of increased load. The characteristics of composite materials obtained during the experiment (exemplified by fiberglass made using various types of hardeners) make it possible to predict an increase in the stability and operation safety of a collapsible pipeline made of composite materials due to possible bending with a smaller radius (compared with similar steel pipelines) when laying it on highly rugged terrain.

TECHNICAL SERVICE IN AGRICULTURE

55-59 1325
Abstract

Based on the analysis of the working condition of the cradle-mounted pumps and the specific defects of protective bushings, the authors offer a technological solution for increasing the wear resistance of the outer surface of parts by the method of electromechanical surface hardening (ESH). The article describes the effects of progressions in the structure and microhardness of the surface layer of bushings made of steel 45 and U8. The authors experimentally found that the microhardness of the samples after ESH increased from 240 НV to 765 НV for steel 45 and from 340 НV to 876 НV for steel U8. The authors designed a stand, conducted wear tests of the samples, and reproduced the application environment of the "protective sleeve - stuffing box" connection of the cradle-mounted pump. The test results have shown that, compared with standard technologies for strengthening bushes, ESH increased the wear resistance of specimens from steel 45 in 3.1 times, while those of steel U8-1.9 times. In particular, using samples made of U8 steel after ESH, instead of serial bushes made of steel 45, may increase the wear resistance of products in 6.1 times. The research results give reasons to recommend the ESH technology to improve the wear resistance of protective bushings during their manufacture and the repair of the cradle-mounted pump.

60-64 76
Abstract

Modern transport and technological machines operate under the seasonality conditions of agricultural operations and significant energy loads. Universal joints of unequal velocity, being part of mechanical power transmissions, work under adverse conditions and limit equipment reliability. It was established that the temperature mode of the bearing assemblies of the universal joints affects the wear rate of their working surfaces. When the temperature in the friction zone increases due to mechanical operation and heating from the environment and adjacent heat sources, boundary friction and temperature conditions exceeding the level of material self-tempering occur. As a result of research, the universal joints (RU199508) were designed to ensure the intensification of cooling its bearing units directly in the maximum heat generation zone during the universal joint operation. Numerical simulation was performed according to the thechinque of calculating radiators for a universal joint with a cross K 040 GOST 13758-89 on needle bearings No. 804704 K5. The results showed the size of the outer surface area that is sufficient for its cooling. When the maximum values of the fracture angle of the universal joint, torque, angular velocity, and efficiency of 0.99 are combined, its bearing units are effectively cooled. It has been found that if the efficiency of the bearing assemblies is less than 0.952, their surface is no longer sufficient to provide efficient cooling and maintain thermal balance conditions in the friction zone. The use of the radiator can increase the heat transfer area by 19%. The radiator ribs fixed on the side surfaces of the yoke eyes with a thickness of 2 mm and a distance of 4 mm and a total area of 166.1 cm2 will ensure the operability of the bearing units. It will remain satisfactory even if their efficiency decreases to 0.943 as a result of mechanical wear.

POWER SUPPLY AND AUTOMATION OF AGRICULTURAL PRODUCTION

65-71 114
Abstract

Using low-power circular saws in farm workshops is characterized by the variety of operating modes determined by the nature of cuts. To increase the efficiency of circular saws when cross-cutting wood, use can be made of inertial energy storage devices in the form of flywheels. However, with longitudinal cuts, the kinetic energy of the flywheels quickly dries up, and it takes a long time to replenish it. To reduce the restoration time of the required saw disk speed, the authors propose using the rotor of an auxiliary electric motor as a flywheel. The regulator automatically controls the auxiliary electric motor according to the current value in the power supply circuit of the main electric motor. To avoid self-oscillations of an unacceptably high frequency, the static characteristic of the regulator must contain a section with an ambiguity zone. This is achieved by using a Ladder Diagram and a logic gate or a microprocessor. The relay-contact circuit includes five electromagnetic relays, a time relay, and two magnetic starters. The time relay aims to eliminate false alarms by ensuring that the regulator is not susceptible to inrush current. To implement the algorithm for controlling an auxiliary electric motor, it is possible to use the logical elements "AND" and "OR," included according to the proposed scheme. An effective measure of increasing the reliability and reducing the regulator size is the use of the ARDUINO microprocessor together with semistors installed in the power circuits of circular saw motors. The controlled double-motor electric drive of the low-power circular saw reduces energy consumption when cross-cutting wood and improves working conditions and productivity when ripping.

72-79 119
Abstract

To optimize the modes of operation of the power system, improve the power supply reliability to consumers and improve the quality of power supplied to the grid, power storage systems are used as the main and backup power sources. The analysis of the practical experience of using the accumulation system is rather topical nowadays. The authors analyze the practical application in the 0.4 kV power grid "Orelenergo" of an electric energy storage system in the form of a 20 kWh storage device of the MRSK2.0/ESS-50.40 type, installed to improve the quality of electric energy. The article gives an overview of the operating modes of the system's storage energy and provides the results of an analysis of its control algorithms. It is established that a power grid with unbalanced load application of the considered storage system has worsened operating parameters. This problem arises due to the following design shortcomings: no dependence of the charging/discharging intervals of the drive on the load schedule of consumers, no phase-by-phase control of power output and charging, no shutdown algorithms in an emergency in the power grid. The article concludes with the statement about the incorrect selection of the accumulator intended for correcting power quality indicators. The authors provide recommendations to improve the energy storage systems designed to enhance the quality of electricity to avoid the identified shortcomings.



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ISSN 2687-1149 (Print)
ISSN 2687-1130 (Online)