Vol 87, No 6 (2020)
- Year: 2020
- Articles: 11
- URL: https://journal-vniispk.ru/0321-4443/issue/view/3690
Full Issue
Articles
Creation and study of the properties of multicomponent biofuels for tractor diesel engines
Abstract
There is an interest in unconventional fuels, their feedstock are renewable resources of various origins, intended for the production, primarily, of biofuels. Biofuel prices are commensurate with the prices of petroleum-based fuels, and in some cases biofuel prices are even lower. The most significant properties of biofuels for operation do not coincide with the properties of commercial diesel fuel. Due to this, when converting ICEs, originally created for operation on diesel fuel, for biofuels, a list of problems is indicated. One of the productive areas of internal combustion engine adaptation can be the use of multicomponent blended biofuels. Expansion of multi-fuel diesel engines and the approximation of the required properties of biofuels to those for commercial diesel fuel are more expedient to achieve by using multicomponent compositions, the result is that the properties of one fuel can compensate the properties of another. Research in the field of heat engines is usually based on the acquisition of bench test data. Considering the length and complexity of this path, elements of scientific planning of the experiment are increasingly used. To reduce the number of experiments, experimental design based on the Box-Behnken three-factor design was applied. Regression equations were built, the adequacy of the obtained models was assessed, and the significance of its coefficients was evaluated. Based on the data obtained during the research, the percentage of the ingredients of the biofuel composition was determined taking into account the conditions of sufficient stability and kinematic viscosity. A modernized design of the power supply system of an agricultural tractor has been developed for its operation on a biofuel composition. It allows to maintain its viscosity-temperature properties within the framework of the current standard, regardless of the ambient temperature. The confirmation of the possibility of tractor operation on the developed composition of the new fuel was obtained experimentally.
Traktory i sel hozmashiny. 2020;87(6):6-12
6-12
Study of the diesel engine working process during its operation with a fuel injection pressure of 300 MPa
Abstract
The paper presents the simulation result of the influence of the ratio of the diameter of the combustion chamber Dкс to its depth hкс and boost pressure рк on the characteristics of a 1ChN 12/13 single-cylinder engine with an injection pressure of 300 MPa at a crankshaft speed of 1400 min-1. The simulation was performed with Dкс/hкс from 3,4 to 10,0, and рк from 0,15 to 0,45 MPa. The results show that the engine achieves the best performance, nitrogen oxides NOx in the exhaust gases decreases at Dкс/hкс = (7,8-10), and the pressure рк from 0,25 to 0,35 MPa. At рк = 0,35 MPa, Dкс/hкс = 10, the indicated power increases by 7,1 %. NOx reduces by 68 % but soot, CO, HC increase 4,5, 9,5, and 2,2 times, respectively. The results also show the impact of the boost pressure on spray characteristics. The boost pressure increases, the penetration, and the tip velocity decrease, but the spray angle changes a little. While the combustion chamber diameter changes, the penetration, and the spray angle change a little, and the tip velocity varies much. Changing the boost pressure is a means of redistributing the amount of fuel burned in the jet and near the wall of the combustion chamber. With an increase in the boost pressure, the proportion of fuel that burns at the beginning of the combustion process under conditions of volumetric mixing increases, while at the end of the combustion process, a large concentration of fuel is located near the combustion chamber wall.
Traktory i sel hozmashiny. 2020;87(6):13-27
13-27
Modern agriculture technologies and equipment - trends of an AGRITECHNIKA 2019 exhibition
Abstract
The world largest specialized international agricultural exhibition AGRITECHNICA 2019 took place in Germany on 10-16th of November, 2019 at the Deutsche Messe exhibition hall in Hannover. The exhibition hall covered an area of over 320,000 m² and included 28 sites. All the world-leading companies in the industry were represented at the exhibition. Around 600 new companies used this international market platform to introduce their products. The slogan of the exhibition AGRITECHNICA 2019 is: Global Farming - Local Responsibility. About 300 new products were registered during the exhibition. The electromechanical gearbox EAutoPower was awarded by gold medal. Other 39 winners were awarded by silver medals. The exposition mostly included models of self-propelled traction and harvesting machinery, as well as machinery for tillage and crop care. Special attention was paid to improvement of the undercarriage systems and particularly to removable tracked running systems for tractors and other self-propelled vehicles with its tracked and wheeled-tracked embodiment versions. Almost every company showed different kinds of automation and robotization solutions for partial operations in agriculture, both for basic tillage and weed control. The big attention is drawn to the significant contribution of the results of cooperation of individual manufacturers to the formation of the overall image of the exhibition. Labor decentralization tendencies to achieve the best results by both complete machines production and separate components release were noted. The domestic manufacturer Rostselmash received particular acknowledgment by winning a silver medal for the development of night vision system RSM Night Vision. Everything mentioned above allows us to conclude that, undoubtedly, the level of technical and technological preparation of agricultural machinery and equipment is increasing, which entails an expansion of the technological component of agricultural work.
Traktory i sel hozmashiny. 2020;87(6):28-40
28-40
Road holding ability I.P. of machine-tractor unit during plowing
Abstract
The discrepancy between the working width of the plow and the width of the tractor leads to asymmetry of the arable units. The geometry of the share surface of the reversible plow contributes to the generation of lateral forces on the working tool. All this contributes to the imbalance of the working body and the deviation of the tractor from straight-line movement during plowing. To maintain a straight line, the driver has to correct the vehicle movement every 5-10 meters, which makes him more tired. To study the causes of lateral slip of the plowing unit, a mathematical model was built. It consists of the equations of controlled motion and equations of uncontrolled shift of the tractor under the action of external forces from the plow. The description of the force interaction of the propeller with the ground is based on the mathematical theory of friction, taking into account anisotropy and elastic properties in contact. On the basis of the passive shear model, the hodograph of the maximum force shifting the tractor from the side of the working tool is constructed. It has been established that the shear force reaches its maximum adhesion value only in the case of translational shear, when its line of action passes through the center of gravity of the tractor. In all other cases, the shift (pull) of the tractor is carried out by a force of a lower value. The features and assumptions of the model are formulated in relation to the tracked and wheeled tractors. As a result, it was found that regardless of the direction of the lateral displacement of the plow draft resistance, the tractor is pulled towards the plowed field. The result of the numerical experiment showed that the main reason for the drift of the wheeled arable unit is the different type of soil along the sides of the tractor, but not the displacement of the plow traction resistance.
Traktory i sel hozmashiny. 2020;87(6):41-49
41-49
Experimental evaluation of traction properties of ultra-low pressure tires
Abstract
Currently, mobile power tools equipped with ultra-low pressure tires are widely used in agriculture when conducting field work in the early spring. For these power tools, fundamentally new wide-profile tires with low load capacity have been developed, featuring ultra-low intra-tire pressure (10-80 kPa), increased profile width, low ply (2-4), high elasticity and soil-covering tread, which in turn provides the necessary traction qualities. Due to the high elasticity of these tires and the relative radial deflection (up to 25 %), the contact area of the tire with the soil increases and the specific pressure decreases. It was determined that due to the cost parameters, a wide range of ultra-low pressure tires, as well as specific features of the tests, they remain insufficiently studied at the moment. In this regard, we conducted bench tests and determined the basic and traction characteristics of the ultra-low pressure tire with a dimension of 1020×420-18 model Bel-79. We derived equations for the dependence of tire performance on various factors. Found that when driving on a concrete supporting base traction properties of the tire are improved with the increase of the internal pressure of the tire and the load on the wheel when driving on the field, prepared for sowing Lucchini support-coupling indicators is observed with a decrease of the internal pressure of the tire and load wheel. It was noted that the results of the tests can be used as reliable initial data for the development of mathematical models of the movement of various mobile power vehicles equipped with ultra-low pressure tires.
Traktory i sel hozmashiny. 2020;87(6):50-58
50-58
Analysis of experimental researches of the tractor equipped with an elastic-damping mechanism in the transmission when moving in the composition of the transport tractor unit
Abstract
The cargo transportation is an integral and energy-consuming part of agricultural production. To improve the energy performance of transport tractor units (TTU), an elastic-damping mechanism (EDM) installed in the tractor transmission was developed. An experimental study was conducted to identify the influence of the EDM on the operation of the tractor as part of the TTU, when it is moving on a dirt road in the 9th gear of the main speed range of the gearbox (GB) of the tractor. A tractor of traction class 1,4 was used. Energy sensors were installed on the main elements of the tractor. The energy performance of the tractor with a transmission equipped with the EDM and the tractor with a factory transmission are determined. A decrease in fuel consumption by 7,3 %, a decrease in traction forces from an aggregated trailer by 19,9 %, a decrease in the amplitude of fluctuations in traction forces by 28,3 % and a decrease in skidding of the driving units by an average of 9,7 % were revealed. A graph describing the dynamics of changes in the skidding of the driving units of a serial tractor and a tractor with the EDM in time is constructed. The statistical processing of the skidding indicators is performed. A decrease in the amplitude of fluctuations in the coefficient of skidding by 16,3 % was revealed. The obtained results of experimental studies indicate that the tractor as part of the TTU with the EDM in the transmission has better performance compared to a serial tractor and has a lower load on the engine, gearbox elements and driving wheels of the tractor.
Traktory i sel hozmashiny. 2020;87(6):59-66
59-66
Factors affecting the change in wheel resistance and track depth of wide-grip sprinkler machines
Abstract
The operation of sprinkler machines is accompanied by the formation of a track with undercarriages, leading to an increase in resistance to wheel movement and leading to many negative consequences: over-watering of irrigated areas, an increase in energy expended on movement, an increase in soil compaction, etc. The depth of the track and the resistance to wheel movement depend on many parameters: soil moisture, irrigation mode, soil bearing capacity, wheel geometry, etc. But the greatest influence is exerted by the load on the wheel axle and the air pressure in the tires. The article presents the results of laboratory studies of installations that simulate the undercarriage of sprinkler machines, which showed that while maintaining a constant air pressure in the tires, an increase in the axle load of the pneumatic wheel from 0,1 to 1.0 kN leads to an increase in the track depth to 4 cm, and also a linear increase in the resistance to wheel movement. With an increase in the pressure generated by the pneumatic wheel, the permanent deformation, the depth of the track, and, consequently, the resistance to movement of the pneumatic wheel increases. The track depth increases by 20 % with an increase in tire pressure from 0,5 to 1,0 MPa. With a constant load on the axle of the wheel, the resistance to movement of the pneumatic wheel increases on average by 25 % when the air pressure in the tires rises from 0,5 to 1,6 MPa. Optimization of running systems, the ratio of the load on the axle of the wheel, geometrical parameters and characteristics, as well as the air pressure in the tires is an urgent task.
Traktory i sel hozmashiny. 2020;87(6):67-71
67-71
The influence of the combined coulter operation on the quality and yield of grain
Abstract
The article presents the results of the studies of the effect of the combined paw coulter for multilevel sowing of grain crops and the simultaneous introduction of a starting dose of mineral fertilizers on the quality and yield of grain of soft spring wheat Omskaya 36 carried out in 2019-2020. When sowing using the SKP-2.1M seeder, which was reequipped with combined coulters, where mineral fertilizers were applied below the seeds of spring wheat, the yield increase in the experiments carried out in 2019 by 14 % average in comparison with the control sowing with the SKP-2.1 seeder with serial coulters, where mineral fertilizers were applied to the same soil horizon with seeds. The conducted field experiment in 2020 confirmed the previously obtained results of the coulter performance; the increase in grain when using the combined coulters on the SPK-2.1M seeder was 12,5 %. The difference in grain yield happened due to the different weather conditions in 2019 and 2020. The qualitative indicators of spring soft wheat when sowing with combined openers in comparison with a serial seeder gave an average increase in protein by 7,9 and 4,7 %, and the highest gluten values on the control seeder were in the range of 25,8-27,1 %, and on the experimental SKP-2.1M seeder it was 26,1-28,5 % in 2019-2020, respectively. Thus, according to the results of the laboratory field studies carried out over two years, it was found that the proposed design of the combined coulter for sowing and applying mineral fertilizers below the sowing of seeds is efficient and it contributes to an increase in yield and quality of grain of soft spring wheat.
Traktory i sel hozmashiny. 2020;87(6):72-77
72-77
Algorithmic model for choosing configuration parameters for robotic gripping of agricultural products
Abstract
The solution to the problem of automating the process of collecting agricultural products based on models, algorithms and multicriteria synthesis of the configuration of robotic capture and control of its software and hardware components during physical manipulations with objects of agricultural products is discussed. Performing monotonous physically difficult operations in agricultural production leads to the risk of disorders of the musculoskeletal system of workers, therefore, the use of robotic means for physical contact and manipulation with objects in agricultural production is an urgent task that ensures a reduction in the cost of production, an increase in the quality of operations performed and the labor safety of involved specialists. The variability of the physical and geometric characteristics of the fruits and the methods of their collection does not allow the creation of universal robotic grippers, therefore, active research is currently underway on the design of robotic grippers for manipulating the fruits of individual crops, differing in weight, density, geometry, surface roughness and other parameters. The article describes the developed conceptual model of robotic gripper control, including the description of the manipulator, gripper, sensor system and the manipulated object of agricultural products with various forms, physical and mechanical properties. The article analyzes the physical and mechanical properties of some vegetables and fruits, methods of cutting off the fruit, which should be taken into account when developing robotic grippers. There were discussed a four-stage technique for determining the parameters of robotic gripping, including determining the characteristics of the manipulated object; characteristics of the working environment; determination of the features of the manipulator on which the gripper is planned to be installed, and evaluation of the efficiency of the projected gripper according to a number of criteria. The developed algorithmic model of the choice of configuration parameters for robotic gripping of agricultural products is presented. It provides, based on the analysis of the properties of the manipulated object, the development of requirements for the configuration and gripping control system.
Traktory i sel hozmashiny. 2020;87(6):78-90
78-90
New process for fluffing rotted straw
Abstract
The results of scientific research and practical experience of flax-growing farms have shown that the process of dew preparation of trusts occurs unevenly along the thickness of the stem layer. With prolonged bad weather, flax stalks sprout with grass and are nailed to the soil by rains. In this state, the lower stems in the layer rot and the quality of fibrous products is markedly reduced. Therefore, it is necessary to periodically wrap or fluff the tapes of the stems. Currently, on the country's farms, flax growers prefer fluffing flax-straw belts due to the high productivity and reliable operation of machines in the field. However, existing fluffers confuse the stems and increase their elongation. The authors note that the resulting large disorientation and excessive elongation of the stems in the layer are the main reasons for the low yield of long fiber in the flax mill. Taking into account the indicated problem, the scientists of Kostroma State Agricultural Academy proposed a fundamentally new process of fluffing rotted straw and developed a machine for its implementation. The machine ensures the maximum preservation of the initial values of the structural parameters of the stem layer. The article describes the device and the principle of operation of the new two-line fluffer for flax-straw belts, describes the methodology for substantiating its operating modes and the results of experimental studies. At the same time, it was found that when the prototype of the fluffer is operating on flax-growing belts sprouted by grass and nailed by rain, it is necessary to set the pick-up drum in such a position in which its fingers will penetrate into the soil to a depth of at least 1,0-2,0 cm. The possibility of increasing the forward speed of the unit movement to 3,1 m/s and more without a noticeable decrease in the quality of its operation was also revealed.
Traktory i sel hozmashiny. 2020;87(6):91-100
91-100
Restoration of hydraulic cylinder rods by method of ESA
Abstract
During the operation of equipment, its structural elements under the influence of frictional forces and the environment are exposed to various types of wear. To maintain the rolling stock in a working condition, it is necessary to systematically carry out a large set of measures, such as maintenance, current and overhaul repairs with periodic replacement and restoration of worn parts and assemblies. It is obvious that maintaining the performance of modern machines requires high technical knowledge and modern technology. It is not uncommon for special machinery, including tractors and various agricultural vehicles, to be equipped with hydraulic power systems to perform various heavy operations. The actuating mechanisms of such systems are hydraulic cylinders. One of the main features of their design and operation is that the main and very precise part - the rod in working order is in an unprotected environment, namely in the open air. The specificity of the work of heavy equipment is high dust content, gas pollution and the presence of various abrasive materials in the work area in the form of stones and soil. Under these conditions, the precision, polished rods are subject to significant wear. In this paper, the possibility of restoring hydraulic cylinder rods for small types of wear (scratches and dents of a depth of no more than 0,3 mm) is considered by the method of electrospark alloying (ESA), with the creation of coatings on their working surfaces that are identical in their characteristics to the new ones. Electrode materials and processing modes were selected. Research was carried out to determine the dynamic microhardness of the created coating.
Traktory i sel hozmashiny. 2020;87(6):101-107
101-107