Vol 86, No 2 (2019)

Articles

Heat generation in biofuel tractor diesel engines

Lihanov V.A., Lopatin O.P.

Abstract

While legal restrictions on the use of fossil fuels are being applied to conserve natural resources, mixed spirit fuels, vegetable oils and their esters are attracting increasing attention as promising alternative sustainable energy sources for tractors and agricultural machinery. The paper substantiates the need for the use of biofuels in tractor diesel engines. It is shown that the choice for diesel alternative biofuel with a perspective should be carried out in accordance with the design features of the engine and during its primary tests. In the paper we investigate such environmentally friendly energy sources such as methanol, ethanol and methyl ester of rapeseed oil (MЕRО). Methanol, ethanol and MЕRО have the potential to lead to some solutions to environmental problems, as there are abundant resources for their production and these sources of energy are characterized by relatively low emissions of harmful substances during combustion. The ways of bioethanol production from various raw materials and the process of rapeseed oil methanolysis are considered. It is shown that agricultural enterprises that consume mainly petroleum products as fuel are now quite capable of producing at least environmentally friendly renewable biofuels for their tractors. Experimental studies of tractor diesel engines on biofuels of the following compositions were carried out: alcohol-fuel emulsion (AFE, alcohol (methanol, ethanol) - 25 %, detergent-dispersing additive succinimide C-5A - 0,5 %, water - 7,0 %, diesel fuel - 67,5 %); methanol (88,0 %) and MЕRО (12,0 %). Based on the studies of the thermal performance of tractor diesel engines running on biofuel, the nature of the influence of their work on the characteristics of heat dissipation and defined their numeric values.
Tractors and Agricultural Machinery. 2019;86(2):3-9
pages 3-9 views

The main directions of development of domestic snowmobiles

D'yakov A.S., Novikov V.V., Pozdeev A.V.

Abstract

In recent years, Russia has begun an active economic development of the Arctic zone, including the extraction of hydrocarbons, as well as the development of the Northern Sea Route. Russia has a maximum length of borders in the Arctic, which is almost half of the Arctic coast. Due to the lack of paved roads, more than 10 percent of the population (15 million people) remain cut off from transport communications during the spring and autumn periods. So far, 39 thousand settlements with a total population of up to 2 million inhabitants (including 7,5 percent of the total number of district centers and 6,7 percent of the central estates of agricultural organizations) do not have a connection to the country's transport network by road hard coating. In this regard, snowmobile motorcycles occupy a well-defined niche among all-terrain vehicles operated in the Far North, the Arctic and the Far East, and allows to successfully solve important transport problems. Along with affordability, mobility, ease of operation, maintainability, snowmobile vehicles also has good indicators of specific carrying capacity. Currently, the production of domestic snowmobiles is made in many Russian companies. The article presents an analysis of domestic snowmobile engineering. The results of marketing research of the snowmobile market in Russia is analyzed. The dynamics of the production of snowmobiles of leading domestic manufacturers for 2014-2016 was considered. The main classes of domestic snowmobiles are considered, their comparative assessment is given. The distinctive design features of snowmobiles from the point of view of consumer qualities are given. The main directions of development of domestic snowmobiles of the tourist, utilitarian and children's classes are presented. The ways to improve their technical characteristics and consumer properties are proposed. New models of domestic snowmobiles of 2018 are analyzed.
Tractors and Agricultural Machinery. 2019;86(2):10-17
pages 10-17 views

The general concept of block-modular construction of forest tillage tools

Bartenev I.M., Lysych M.N.

Abstract

The article provides general data on the scale and prospects for the use of block-modular principles for constructing technical objects in various industries, in particular, in agriculture in the development of tillage and sowing units. In forestry, the block-modular construction of tillage tools has not found a wide-spread use, therefore, designs adapted to perform a single technological operation within a specific tech-nology prevail. At the same time, all this variety of specialized machines remains unclaimed, since Forest enterprises at the present stage of development are not capable of purchasing and operating a wide range of equipment and are limited to a very narrow set of obsolete tillage tools. To solve these problems, the author applied block-modular principles for constructing technical objects for developing a set of tillage forest tools. A constructive description of the proposed basic modular platforms (single-bar rear-mounted, double-sided rear-hung and front-hung) and various interchangeable modules of the working bodies is given. The possible options for the layout of modular tools in 3D CAD software SolidWorks have been worked out and an example of machine tractor unit based on a multifunctional modular plow has been presented. The analysis of the structures confirmed that the tools equipped with various working modules are capable of effectively performing all operations on basic soil preparation, carrying out agrotechnical treatments, as well as partly sowing and planting of forest crops in various conditions. Thus, a large variety of used forest tillage equipment used can be reduced to a narrow range of highly adaptable modular tools.
Tractors and Agricultural Machinery. 2019;86(2):18-26
pages 18-26 views

The study of soil crumbling when using new working bodies

Parhomenko G.G.

Abstract

Comparison of quality indicators of the results of research and testing on machine-testing stations with with their normalized values characterizes the compliance or non-compliance with the agrotechnical requirements of soil tillage machines and working bodies. According to agrotechnical requirements, one of the main indicators characterizing the quality of tillage is soil crumbling. The crumbs of the field surface depend on the quality of crumbling as with the predominance of the required size of lumps in the treated soil layer, an even field surface is observed. At a high quality of crumbling, soil particles smaller than 1 mm from the upper layer spill to the lower ones, preventing erosion. Objective: to characterize the quality of crumbling of the soil when using new working bodies in terms of compliance with agrotechnical requirements and compare it with analogues by the technological adapter. Compliance with the agrotechnical requirements of the new working bodies was determined according to the regulatory docu-mentation for soil tillage testing machines. It was found that by the quality of the layer crumbling (up to 98,5 %) and by reducing the number of erosion-hazardous particles in the upper soil layer (up to 18,13 %) new working bodies are superior to analogues by the process adapter. A positive impact on the quality of crumbling has had the use of elements of the working body, made in a curvilinear form (87,8-98,5 %) compared with a flat-cutter (65,1-76,8 %). Modernization of the flat-cut design with the possibility of self-setting the cutting angle at the angle of the natural cleavage of the soil allowed improving the quality of crumbling to 80,5-82,0 %, and the use of alternative materials - to 82,0-84,8 %. In terms of the quality of crumbling of the reservoir, new working bodies correspond to agrotechnical requirements of tillage pre-sowing. This reduces the number of technological operations for additional loosening and leveling the field surface before sowing. This reduces the number of technological operations for additional loosening and leveling the field surface before sowing. It was established that new working bodies are not inferior in terms of agrotechnical indicators to modern technical means for tillage.
Tractors and Agricultural Machinery. 2019;86(2):27-34
pages 27-34 views

Computer simulation of the «engine - working machine» mechanical system

Delyagin V.N., Dobrolyubov I.P.

Abstract

There was investigated the application for the purpose of diagnosing the technical condition of the unit, the internal combustion engine (ICE) - the working machine (WM) of advanced computer models of internal combustion engines with the additional function of determining the technical condition of machines (mechanisms) driven by the internal combustion engine. The mechanical system «ICE-working machine» is considered as a three- and two-mass system with lumped parameters. Equations of equilibrium moments are made that act on the selected concentrated masses, taking into account various nonlinearities (dry and viscous friction, dead zone, etc.), elasticity of the shafts and joints. The block diagrams of the ICE-PM system in the form of transfer functions are given. A computer simulation of this system was carried out with the presentation of the obtained computer structural diagrams and graphs of dynamic processes (angular velocities and shaft accelerations, etc.). Introducing into these schemes the values of the parameters characteristic of a specific unit ICE-PM by varying the values of different moments, it is possible in the static and dynamic modes to evaluate their influence on the technical state of ICE-PM. The use of a computer model allows to take into account the influence of these factors on informative diagnostic signals reflecting the technical condition of the internal combustion engine, since the level of signals characterizing the power indicators of the internal combustion engine is significantly higher than the level of signals reflecting elasticity and nonlinearity. The developed computer block diagram can be directly used in diagnostic complexes based on microprocessor systems, microcontrollers and microcomputers for diagnosing internal combustion engines and working machines under operational conditions.
Tractors and Agricultural Machinery. 2019;86(2):35-40
pages 35-40 views

Optimization of parameters and modes of operation of the spiral-screw roller

Maslov G.G., Evglevskij R.O., Cybulevskij V.V.

Abstract

The method of planning a two-factor experiment substantiates the optimal parameters and operation mode of the spiral-helical roller for compacting the soil in order to create its optimum density in the sowing layer, which ensures friendly shoots of the sown seeds of cultivated plants and their sustainable development. The studies were carried out using the provisions of the experiment planning theory and the main measurement methods written in the regulatory documentation. The quantitative factors of the mathematical planning method are the design parameters and operating modes of the press roller. The Vк (plan) was used for its optimization, and the density of the soil in the rolled layer was taken as the optimization criterion (response), which depends on the size of the ballast weight attached to the frame of the roller and the operating speed of the unit. The levels of variation of the factors are chosen so that their optimal values, calculated theoretically, fall into the center of the interval of variation. Using the obtained regression equations in canonical form, we obtained hypersurfaces of dependence of soil density in the sowing layer on the operating speed of the aggregate and ballast weights, as well as dependencies of two-dimensional sections of soil density. The center of the experiment lies within the scope of the experiment. The value of the optimum density of the soil in the sowing layer of 1,25 g/сm3 at a working speed of the unit of 7,6 km/h and a ballast weight of 42,4 kg was obtained.
Tractors and Agricultural Machinery. 2019;86(2):41-44
pages 41-44 views

Substantiation of the design and technological parameters of the spiral roller for the onion harvesting machine

Sibiryov A.V., Aksenov A.G.

Abstract

The peculiarity of harvesting onion sets is that the composition of the impurities of the onion-soil heap coming from the digging working bodies to the separating working bodies is made up by soil lumps commensurate in size with the onion-seed bulbs, which are difficult to separate at slotted (bar elevators, screens) working bodies. This problem is most relevant in the selection of onion sets from rolls, because together with the bulbs, the separating working bodies receive the soil layer, loosened by the digging working bodies in the first phase of harvesting onion sets, which are the basis of fractional composition and is hardly separable on slotted working bodies. This circumstance is explained by the fact that after the soil is digged together with commercial products, a significant amount of soil lumps, which are difficult to separate on the separating working bodies and lead to damage of root crops and bulbs during their interaction, come to the separating working bodies. In addition, the release of soil lumps on the slit working bodies (rod conveyors and screens) occurs according to dimensional signs and this does not lead to a solution to the existing problem - separation of soil lumps commensurate in size with onion bulbs. Conse-quently, to ensure quality indicators of harvesting onion sets, namely, the completeness of the separation of bulbs from soil impurities, it is necessary to ensure a reduction or complete exclusion of the receipt of soil lumps on the separating working bodies in the second phase of harvesting, which intensifies the onion harvesting roller. The article presents the design of device for onion harvesting, which intensifies the maximum completeness of separation of onion heaps from soil impurities, including comparable soil lumps during the second phase of onion harvesting. The results of theoretical studies of the device for on-ion harvesting based on the design and technological parameters are given.
Tractors and Agricultural Machinery. 2019;86(2):45-50
pages 45-50 views

Brake force of tracked vehicles

Kopotilov V.I.

Abstract

It is commonly supposed that the slowing down and stopping of vehicle is caused by adhesion of its tracks to the dirt surface. However, force analysis shows that, although these forces play an important role during braking, the longitudinal components of the internal forces applied to the shafts of the vehicle’s braked drive wheels and the front support rollers of the tracked propulsion are directly responsible for its deceleration. The sum of these longitudinal forces directed against the motion of the tracked vehicle constitutes the braking force of the tracked vehicle. The value of this total braking force is ultimately determined by the ratio of the braking torque developed by the friction forces to the radius of the drive wheels with which the braking devices are coupled. Since when braking a tracked vehicle, the longitudinal reaction is balanced, it cannot be the direct cause of the deceleration of the vehicle, i.e. its braking force. In addition, the longitudinal reaction applied to the lower fixed part of the track does not perform mechanical work and cannot absorb the kinetic energy of a moving vehicle. This work is performed by the internal braking force Ртор, which develops negative (braking) power during braking. It turns out that during braking, the longitudinal reaction is needed not at all to cause a slowdown, but as an external force, to balance some of the internal forces of the tracked vehicle. As a result of its action, the unbalanced part of the internal forces forms the internal braking force, which directly causes the machine to slow down and stop. In this case, the longitudinal reaction of the supporting surface, without which the formation of an internal braking force is not possible, limits both the lower and upper values of the latter, and these forces themselves are numerically equal. The fact that the braking force of a tracked vehicle, like its traction force, is an internal force, does not contradict theorems on the movement of the center of mass or the change in the amount of motion of a mechanical system, which are valid only for isolated mechanical systems that do not have a source of active internal forces.
Tractors and Agricultural Machinery. 2019;86(2):51-55
pages 51-55 views

Features of the spectra of loads on the units of mobile agricultural machines in the field when delay in external influences

Partko S.A., Groshev L.M., Sirotenko A.N., Vojnash S.A.

Abstract

The problem of choosing the oscillatory parameters of mobile combine harvesters leads to the development of dynamic models that ensure the normal functioning of machines, as well as to consider these parameters in the probabilistic aspect and, consequently, to assess their dispersion. The main type of impact is the impact created by the unevenness of the path of the mobile machine and the change in the physical and mechanical characteristics of the soil. Such problems are solved with sufficient accuracy for practice in the linear formulation. In the article, external influences in multidimensional dynamic systems are presented in matrix form. Matrix of spectral densities when calculation of statistical characteristics in the presence of mutual relationships lead to the need to calculate the elements of both the main and secondary diagonals, which leads to the complication of calculations. Calculation of correlations between impacts determines the form of the matrix of spectral densities of external influences. When calculating statistical characteristics, relations taken into account lead to a complication of calculations. Therefore, it is advisable to bring the matrix of external influences to a diagonal form in order to obtain matrices of uncorrelated influences. The calculations of the spectral densities and vibrational intensities for mobile machines of the agroindustrial complex made it possible to establish that the same results are obtained only for vehicles with weak functional connections, when moving along a field micro profile creating an uncorrelated external influence. Recommendations on the practical use of calculation formulas are given.
Tractors and Agricultural Machinery. 2019;86(2):56-60
pages 56-60 views

Regulation of tractor diesel engine operation modes by missing fuel distribution

Potapov V.I., Gajsin E.H., Galiullin R.R., Rozhkov A.S.

Abstract

The article discusses the improvement of the effective performance of diesel engines of tractors at idle and low loads. A possible way to improve performance in such modes is deactivation of cylinders. However, this method of regulation has a number of disadvantages, in particular, a step change in the characteristic of specific fuel consumption. The goal is to increase the fuel efficiency of tractor diesel en-gines when regulating the operation modes by switching off the cylinders. Studies were conducted on tractor diesel engines 2Ch105х120 and 4Ch105х120, equipped with distribution pumps of dispenser type. Tests of 2Ch105х120 and 4Ch105х120 diesel engines showed that as the cylinders were disconnected, the engine efficiency reduced even at low loads. Upon further testing, it turned out that in order to achieve the distribution effect of the cylinder shutdown needed when working with the pump of the distribution type, a cyclic fuel supply correction to the operating cylinder is required. A characteristic feature of distribution type pumps was that shutting off the supply to one cylinder significantly changed the cycle flow to the other remaining cylinder. In one case, it turned out to be more than the required one and with its decrease, the specific fuel consumption decreased. In another case, when the cycle feed was less, the specific fuel consumption could be possible to reduce by its increasing. It turned out that with a simple shutdown of the cylinders, there remains an unrealized zone in which you can additionally receive fuel economy. One of the ways to implement this zone can be the transition from disconnecting cylinders to disconnecting individual fuel supplies. It is possible to implement this method by equipping the diesel fuel system with an electronically-controlled high-speed valve, which, depending on the engine's operating mode, will re-alize the necessary omission of fuel supply and adjustment of the cycle feed amount for individual cylin-ders. A Denso valve was used as a solenoid valve to shut off the fuel supply. An electronic regulator has been developed to control the operation of the cross-valve. The test results showed that when switching from simple shutdown of cylinders to regulating the operation modes by skipping individual fuel feeds, the specific fuel consumption changed smoothly and the power range at which the diesel engine operates in this mode remains the same as during work with all cylinders.
Tractors and Agricultural Machinery. 2019;86(2):61-66
pages 61-66 views

The transporting ability of the rotor of the soil-cultivating loosening and separating vehicle

Pashchenko V.F., Syromyatnikov Y.U.

Abstract

The subject of research is the process of interaction between the working bodies of the rotor of a soil-cultivating loosening and separating vehicle. The object of the study is a rotor knife, the transporting ca-pacity of which is determined by the size of the grooves left in the soil with a cross-sectional shape close to the trapezoid shape. The physical process of interaction with the soil of the rotor blade of a loosening and separating device is considered. In the first phase, when the knife is buried in the soil, a soil build-up is formed in front of the knife. In the second phase of the knife operation, the soil is under the influence of a build-up, the magnitude of which increases until the internal stresses in it reach the limit values and do not partially break it down. In the third phase of the impact of the knife on the soil, the build-up begins to separate from the main part of the soil and is discharged from the separation grid. The direction and mag-nitude of the displacement of the soil, as well as the parameters and shape of the grooves formed after the passage of the knife, are determined. It has been established that the thickness of the applied soil layer to the loosening and separating device and the angle of the rotor knife break have the greatest effect on the transporting ability of the rotor blade, the width of the rotor blade has the least effect. It has been proven that an increase in the transporting capacity of the rotor at the initial moment of entry of the knife into the soil can be achieved mainly by reducing the angle of entry of the rotor knives into the soil. The theoretical studies were applied using mechanical and mathematical modeling of the interaction of the working bodies with the soil. Baseline information to substantiate the study was obtained experimentally and by analyzing literary sources. The urgency lies in the fact that increasing the transporting ability of the rotor by reducing the angle of entry of knives into the soil will give the opportunity not to change the magnitude of the radius and angular velocity of the rotor which determine the energy performance of the loosening and separating device.
Tractors and Agricultural Machinery. 2019;86(2):67-74
pages 67-74 views

The influence of the angle of loosening of the working body of an agricultural instrument on the intensity of destruction of soil aggregates

Myalenko V.I.

Abstract

The consequence of mechanical tillage, in addition to achieving positive results, are also negative consequences associated with the destruction of the primary soil microaggregates. Some of the soil microaggregates that are in direct contact with the surface of the working body of the agricultural tools are crushed and destroyed. Directly microaggregate is a sustainable soil aggregate, or structural unit of ripe soil. In the center of the microaggregate there are solid particles of the parent rock, as a rule, these are SiO2 silica, around which there is a dense organic shell. The very fact of the destruction of the primary soil microaggregates in the treated soil layer is confirmed by the wear of the working bodies of agricultural tools, which are carried out by abrasive particles of the parent rock due to the destruction of the microaggregates themselves. It turns out that the intensity of wear of the working bodies indirectly characterizes the intensity of the destruction of soil microaggregates. As a result of the processing of ripe soils, its loosening in order to ensure at least 50 % of porosity, simultaneously grinding, destroys a certain layer of the structure of the aggregate structure of the same soil. These contradictions form the problem of finding a solution, reducing the possibility of destruction of the aggregate structure of the soil when it is processed by agricultural tools. The purpose of this work was to identify the influence of the geometrical parameters of the working bodies of agricultural tools on the intensity of destruction of microaggregates in the adjacent soil layer. This goal was achieved through theoretical studies and with the use of simulation laboratory tests, as a result of which the intervals of the geometric characteristics of the working bodies, at which the smallest destruction of soil microaggregates is achieved, are determined.
Tractors and Agricultural Machinery. 2019;86(2):75-79
pages 75-79 views

Determination of the structure park of semitrailed and trailed machines for applying solid mineral fertilizers

Latyshenok M.B., SHemyakin A.V., Terent'ev V.V., Andreev K.P., Makarov V.A., ZHuravleva O.I.

Abstract

The yield of crops depends on the effective use of solid mineral fertilizers. The effectiveness of the mineral fertilizers themselves depends on the method and quality of their application (uniform distribution and place of supply to the roots of plants). In recent years, the Russian market has a large number of imported machines and equipment for the application of solid mineral fertilizers, which creates certain difficulties in their maintenance and operation and the lack of a policy for the production of domestically made machines. The main advantage of trailed and semi-mounted machines designed for fertilizer application is a large bunker volume, reduced load on the tractor and the width of the grip. The article describes the technology of mineral fertilizers, considers the need for trailed and semi-mounted machines with the corresponding cost of working time and determine the book value of machines at the manufacturer. In the study of existing technologies of fertilizer application, the volume and timing of application, the required number of vehicles, as well as technical, operational and technical and economic indicators, five baseline options were considered, differing from one another by the degree of consideration of the real situation. As a result, the estimated number of machines required for each option was obtained. Based on the study, it was concluded that for the qualitative use of solid mineral fertilizer application technology, it is necessary to reduce the loss of working time, reduce vehicle downtime for operational reasons, provide agricultural producers with high-performance spreaders and loaders.
Tractors and Agricultural Machinery. 2019;86(2):80-84
pages 80-84 views


This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies