Vol 85, No 3 (2018)

Articles

Analysis of hydrodynamic characteristics of sprays of nozzles of ICE

Altukhov S.V., Shukhanov S.N.

Abstract

The automotive and tractor machinery plays an important role in technical support of agro-industrial complex at the present stage of development of agricultural production. The main energy source of these vehicles are internal combustion engines, which work is influenced highly by spraying nozzles. A comprehensive study of the qualitative indicators of their functioning allowed authors to find new practical and theoretical solutions. In the study of the hydrodynamic characteristics of spraying nozzles, a theoretical analysis was used. When replacing bayonet sprinklers in the vortex chamber diesel with multi-jet, the hydrodynamic parameters of the fuel injection process were performed. Three types of sprays were tested. The studied sprayers differ from each other in the size of a flow section, mass of a needle, the sizes and a location the holes. It causes various sizes of delivery pressure of fuel, an oscillation frequency of a needle of the sprayer and other parameters. The received calculated dependences show that with increase in a flow section with a constant residual pressure critical pressure of a wave of supply of fuel increases. So with a residual pressure of 3 MPas critical pressure of a wave makes respectively 10, 14,4, 16,7 MPas for sprays of three types. Increase in residual pressure causes increase in critical pressure of a supply wave. Due to the need of increase in critical pressure of a fuel supply wave for multiple-jet sprayers (in comparison with bayonet) we will consider influence of the nozzle spring tension pressure on the needle opening delay time. Results of calculation of delay of opening of a needle of a nozzle for bayonet and multiple-jet sprays are presented. Studies show that the size of delay of raising of a needle of a nozzle with the multiple-jet spray with a pressure of the beginning of injection Pz = 15 mpa is closest to delay size for the bayonet spray. The result revealed that the frequency of natural oscillations and their duration slightly differ from each other (no more than 5 %). Hence it can be assumed that the use of the experimental sprayers will not exert the considerable impact on operation of sprayers from the point of view of vibration characteristics.
Tractors and Agricultural Machinery. 2018;85(3):3-6
pages 3-6 views

Efficiency of surface treatment of soil by a stubble multifunctional cultivator

Maslov G.G., Yudina E.M., Zhurij I.A.

Abstract

The effective application of the stubble cultivator on surface tillage is justified simultaneously with the introduction of solid mineral fertilizers. The atomization of the soil in comparison with the disk tools decreases in 1,5...2 times. Using the example of the proposed multifunctional stubble cultivator with the device for simultaneous application of mineral fertilizers, the possibility of using the cost and loss function (the cost of carrying out the amount of work and the loss of the future crop due to a violation of the optimal duration of work) is proved to optimize the duration of work. A block diagram of the algorithm for optimizing the parameters and operating conditions of a multifunctional stubble cultivator is presented based on the criterion of the optimal value of the traction factor of a given tractor, taking into account its traction characteristics and the dependence of the coefficient of the resistivity of the cultivator on the working speed of movement, the depth of processing and the specific material consumption, with consideration of the mass of fertilizers applied. In the objective function of optimizing the duration of the work performed, the cost of the cost includes the operating costs for the specified unit for the planned scope of work. With an increase in the duration of these works, costs are reduced, and the cost of future crop losses, on the contrary, increases. The sum of costs and losses has an extremum, which determines the optimality of the solution. The dependence of the cost of losses of the future corn grain crop on the duration, the amount of work, the purchase price of the harvested crop and the intensity of losses for each day of the violation of the optimal period of stubble cultivation of the soil with simultaneous application of mineral fertilizers is given. With the help of the obtained cost and loss function, the optimum duration of stubble cultivation of the soil was established with the simultaneous introduction of solid mineral fertilizers using the example of the machine-tractor unit as part of the MTZ-1221 tractor and the stubble cultivator KSU-3 with the device for simultaneous application of solid mineral fertilizers.
Tractors and Agricultural Machinery. 2018;85(3):7-11
pages 7-11 views

Parametric optimization of the curvilinear working element for layerwise soil-free tillage

Parhomenko G.G.

Abstract

For effective functioning in conditions of insufficient and unstable moistening of the south of Russia, tillage machines are developed on the basis of the block-modular construction principle with various working elements with replaceable elements. The possibility of a combination of replaceable elements is incorporated in the design of the working element for layer-by-layer soil-free tillage. This working body is equipped with curved, planar rippers or plastic elements. Qualitative indices of the technological process of layer-by-layer soil-free tillage of the working body with a curvilinear ripper, in comparison with others, reach a higher level: 97,4...98,5 % of fractions up to 50 mm, a sharp decrease in the content of erosion-hazardous particles in the surface layer to 15,12...18,13 %. The energy consumption for the functioning of the working element with plastic elements is 6 % less than with the curved ripper. The purpose of the research шы еру reduction of energy costs due to optimization of the parameters of the working body with a curved ripper while maintaining the quality of the technological process of layered soil-free tillage. Experimental studies on the three-factor Box plan for determining the parameters of the working body with a curvilinear ripper have been carried out, which ensures a reduction in energy costs for layer-by-layer soil-free tillage. The criterion for evaluation is the traction resistance of the working body, on which the energy costs directly depend on the performance of the technological process of layer-by-layer soil-free tillage. The greatest influence on the growth of traction resistance is due to an increase in the crumbling bit angle of the barpoint. With increasing speed, a reduction in traction resistance with a lower intensity is observed. This is explained by the less significant effect of the speed of movement of the working member on its traction resistance in comparison with the propagation velocity of the stress wave. With an increase in the depth of cultivation of the soil, the traction resistance increases. When fixing the speed of moving the working element at a level of 2,5 m/s, the optimal value of the depth of tillage is 28...29 cm, the angle of crumbling of the bit is 31...31,5 degrees.
Tractors and Agricultural Machinery. 2018;85(3):12-18
pages 12-18 views

Substantiation of the design parameters of a screw for the variable pitch of a press extruder in the preparation of a loose sunflower meal

Priporov I.E., Kurasov V.S.

Abstract

The purpose of the study is to reduce the energy consumption of extruding sunflower seed waste when obtaining a sunflower meal in loose form on the basis of planning a multifactor experiment. Before the beginning of the experiment, the factors were encoded by performing a linear transformation of the factor space with the transfer of the origin to the center of the experiment and the introduction of new units of measurement along the axes. The natural value of the factor variation interval was determined. Taking into account the review of literature sources, theoretical studies and scientific and technical information, factors of variation were chosen to calculate the density of sunflower meal in the loose form obtained after treating the waste of seeds on a press extruder KMZ-2. After calculating the regression coefficients, a regression equation was obtained describing the density of the sunflower meal in the loose form. A study was made of the homogeneity of the variances of the experimental responses obtained by the Cochran test, and also checked the adequacy of the obtained mathematical model with the help of the Fisher criterion. The angle of conicity of the screw, the pitch of the auger of the 2nd coiling and, to a lesser extent, the 1st coiling, including the pair interaction between the taper angle and the pitch of the screw of the 1st winding, influence the obtaining of the sunflower meal in loose form in the extruder KMZ-2. Based on the results of the three-factor experiment, the optimum design parameters of the variable-pitch screw of the KMZ-2 press-extruder were determined, which have the following values: the cone angle is 30 °, the pitch of the screw of the 2nd coiling is 28 mm, the pitch of the screw of the 1st coiling - 36 mm, which make it possible to obtain a loose sunflower meal with a density of 2139,4 kg / m3 and reduce the energy consumption of extruding sunflower seeds.
Tractors and Agricultural Machinery. 2018;85(3):19-24
pages 19-24 views

Perspective for the development of agricultural mobile energy

Shevtsov V.G., Godzhaev T.Z., Erilina E.V.

Abstract

The analysis of security with the mobile power tools (MPT) on 1000 hectares of an arable land in Russia and some countries of the world is submitted, the created deficiency of tractors on traction classes and type of running systems is disclosed, the dominance in the machine tractor park of wheel tractors of a class 1,4 Belarus 82.1 is revealed. The provided data confirm practical decrease of volume of the machine and tractor park and demand acceptance of the state measures for its restitution. Special attention is paid on the fact that the caterpillar component of the park have dual purpose, which share in the common park approaches now over a zero level is extremely unacceptable for soil and climatic conditions of Russia. It is shown that in statistics of sales of tractors in Russia in recent years the larger share of the market is occupied by agricultural machinery of domestic production. From 2013 to 2016 the share of the domestic enterprises in the value of sales grew from 22 to 35 %. The main vector of development of MPT allocated tendencies of replacement of kinematic communications by the informational, being a systemic basis use of digital technologies. The near-term outlook of the choice of the technological direction of the advancing development of agricultural mobile power tools, competitive at world level, and the prospect of search works on creation of robotic agricultural MPT are considered. It is noted that applications of the integrated and high-precision models of farming, including technologies of precise agriculture, rises the need for the automated and robotic MPT. It is shown that in the near future agricultural robots will automate all hard field work: plowing, landing, application of fertilizers, collecting and transportation, a harvest etc. and will create basically new market of MPT.
Tractors and Agricultural Machinery. 2018;85(3):25-31
pages 25-31 views

Modeling the movement control of a wheeled agricultural machine in real time

Nenajdenko A.S., Poddubnyj V.I., Valekzhanin A.I.

Abstract

The research, which purpose is the development of a motion control system for wheeled agricultural machines, is conducted in Polzunov Altai State Technical University. One of the most important steps in this case is the testing of the developed control algorithms. It is advisable to replace the field trials by real-time motion modeling, which allows to significantly reduce financial and time costs. The developed control algorithm can be conditionally divided into global and local regulation. Global regulation must determine the angle of rotation of the steered wheels (or the angle of the frame break) by a deviation from the specified trajectory, which ensures the motion along the specified trajectory. Input parameters are the specified path of motion, the current coordinates of the machine and the projection of speed on fixed axes. Local control provides the implementation of the set value of the angle of rotation of the steered wheels. To the input of the local adjustment program is given the values of the set and current angles of rotation of the wheels and the direction of rotation of the electric motor of the maneuvering device. The algorithm for determining the required angle of rotation of the wheels is based on the method of predicting the position of the wheeled vehicle through the predetermined forecast time. In real-time tests, the wheeled vehicle is replaced by its mathematical model, obtained using the differential equations of plane motion. The complex of equipment provides registration and generation of the necessary parameters for the operation of the control system in real time. The tests were carried out on the experimental stand «steering - front suspension of the vehicle». The front steerable wheels were rotated by an electromechanical maneuvering device to an angle providing movement along a given trajectory. The motion along rectilinear and curvilinear trajectories was modeled taking into account perturbations from the side of the support surface and without them. When moving along a curvilinear trajectory, the deviation from the specified trajectory does not exceed 0,3 meters at a speed of 3,33 m/s. Based on the results of the experiments, it was established that the implemented control algorithm ensures motion along a given trajectory with a sufficient degree of accuracy.
Tractors and Agricultural Machinery. 2018;85(3):32-38
pages 32-38 views

Influence of the speed of the floating conveyor on the separating ability of the bottom of the inclined chamber

Ozherel'ev V.N., Nikitin V.V., Komogorcev V.F.

Abstract

The results of a laboratory experiment confirming the possibility of preliminary separation of free grain from a combed grain heap prior to its entry into the threshing chamber of a combine harvester are presented. In particular, it is proposed to provide the inclined chamber with a special perforated trellised bottom having elongated holes of a rectangular shape. All research was carried out on the wheat of the variety called Moscow 56. The moisture content of the grain was about 12 %. The speed of the floating conveyor had six levels of variation within the range of 0,5 ... 3 m/s. The angle of inclination of the experimental setup to the horizon was assumed equal to 45 °. The feeding of the combed grain heap was about 10 kg / s with the content of 80% of free grain in it. So according to the results of scientific research it is established that as the speed of the floating conveyor increases, the amount of free grain of the grating bottom that has passed through the holes decreases, and the amount of grain that has descended from it, on the contrary, increases. In this case, the maximum free grain (31,3 %) corresponds to the maximum speed of the floating conveyor (3 m/s). This is due to the fact that during the series of experiments, the length of the separation grid was insufficient. For this purpose, the nature of the process of preliminary separation of free grain from the tow grain heap along the length of the lattice bottom is considered. Extrapolation of this process shows that the length of the lattice bottom, which ensures the complete liberation of free grain from the tow grain heap, should be not less than 1,17 m. The practical implementation of such a technical solution in the construction of a modern combine harvester will increase its productivity when combing plants on the root, while at the same time excluding the possibility of crushing free grain by the working bodies of the threshing device.
Tractors and Agricultural Machinery. 2018;85(3):39-44
pages 39-44 views

Simulation modeling of the volumetric hydraulic drive

Popov A.Y.

Abstract

In the design of a variety of the modern agricultural machines, the hydraulic drive with reciprocating motion for lifting, lowering and moving the working bodies has obtained a wide application. One of the important stages in the design of hydraulic drives and transmissions is a simulation. In connection with the laboriousness of carrying out the full-scale experiment and the cumbersome calculation of mathematical models of hydrosystems, as well as the development of the computing machinery, the simulation modeling has obtained a widespread usage. This type of computer simulation allows to investigate complex systems based on the development of multilink factor models with the visualization of a numerical experiment. The article presents the procedure for the simulation modeling of dynamic processes occurring in the volumetric hydraulic drive. The model is developed on the basis of standard libraries of the computing system MATLAB Simulink. The volumetric hydraulic drive is presented in the form of a structural model and consists of interconnected blocks that on the base of differential equations modeling the operation of a pumping station with a mechanical drive, a safety valve, a three-section four-line hydraulic distributor, double-acting power cylinder with special rod, a hydraulic tank. During the calculation of the simulation model takes into account a change of the modulus of elasticity of the fluid depending on the pressure in the hydraulic system, the parameters of the working fluid, the stiff stop when the extreme positions are reached by the rod of the hydraulic cylinder, the friction between the moving parts in the power hydrocylinder. The developed program allows to simulate working processes at the design stage and obtain the necessary data on the dynamic properties of the hydraulic system in all modes of operation, to demonstrate in the form of graphs and oscillograms, to simplify the analysis of transient processes in the hydraulic system, and also to select the rational design parameters of constituent elements of the volumetric hydraulic drive.
Tractors and Agricultural Machinery. 2018;85(3):45-53
pages 45-53 views

The influence of the properties of materials used to make the working bodies of the stripper header on the quality of the performed process

Bur'yanov M.A., Chervyakov I.V., Bur'yanov A.I.

Abstract

The aim of the inveatigations is to develop the main provisions of the procedure for determining the influence of material properties on the example of steel and ultra-high molecular weight polyethylene (UHMW PE) when they are used to fabricate or cover the outer and inner surfaces of the fairing and the combing teeth of the header, on the quality of the process performed by it. The dependencies and regularities that are integral parts of the previously developed mathematical model of the process of combing grain crops with a single-barrel header are used in the article. As a result of solving the equations, data on the normal and tangential components of the speed of movement of the ear and grain after contact with the test surfaces were obtained. Upon contact with the external surface of the fairing that material would be preferred which the movement along is accompanied by a lower value of the frictional force. During a rebound from the combing tooth and the inner surface of the fairing, the best material is the speed of rebound of the grain from which is higher. The value of the normal forces pressing the ear of winter wheat to the contacting surface was determined in an experimental plant simulating the process of combing the reaper. The coefficient of static friction and motion and the coefficient of recovery upon contact with the surfaces of steel and UHMW PE ears and winter wheat’s grains were determined at its moisture content of 9 %. It has been established that at a header speed of 3 m/s, the frictional force pressing the ear to the outer surface of the fairing from UHMW PE is 1,75 times less than on the steel. After contact with the tooth, the rebound speed of the grain is higher, if it is made of steel. For the accepted characteristics of the harvested plants and the operating conditions of the header, when the grains come into contact with the inner surface of the fairing from the UHMW PE within the friction angle, the loss of grain velocity after the collision is less than on the steel, with the exception of contact with direct impact. Compensation for the reduction in speed within a direct impact on the inner surface of the fairing which is made of UHMW PE can be achieved by varying the angle of inclination of the combing teeth on the drum.
Tractors and Agricultural Machinery. 2018;85(3):54-61
pages 54-61 views

Comparative evaluation of the effectiveness of the vibration protection of the active suspension system with PID control

Kuz'min V.A., Godzhaev Z.A.

Abstract

The pneumatic suspension is used to absorb vibration and provide comfortable labor conditions for transportation vehicle drivers. The cause of increased vibration of the tractor, often, are incorrectly matched elastic-damping characteristics of the cushions of the active suspension system, which can not cope (or cope extremely ineffectively) with fluctuations coming from the external background. Since the realization of an experiment for the dynamic analysis of pneumatic suspension takes a long time, the mathematical models of the vehicle suspension system are used to obtain the response parameters of the pneumatic suspension. In the given article the comparative characteristic of spring’s systems with a cylindrical spring and a linear pneumatic spring as a suspension system is given. To carry out the simulation, the Matlab/Simulink software complex was used, in which, based on the previously obtained values of equivalent rigidity, a simulation of the tractor was built. Since the tractor in this model is considered as a linear system, its spectral function was calculated from the spectrum of the input parameters of the path unevenness and the frequency response of the tractor. These parameters were used to analyze the vibration response of the suspension system to assess the effectiveness of the system and, as a result, assessment of the operator comfort. The algorithm of the proportional integral differentiating (PID) regulation of the suspension system was implemented depending on their output parameters as well. The comparative study shows how the linear model of the pneumatic suspension system controlled by a PID-regulator is able to suppress fluctuations arising from road roughness and whether it is effective than a passive suspension system for a vehicle with a coil spring. The criterion of efficiency in this work was the indicator of the tractor's displacement height.
Tractors and Agricultural Machinery. 2018;85(3):62-67
pages 62-67 views

Testing of the protective device ROPS of the industrial tractor B10

Serov S.I., Naradovyj D.I., Troyanovskaya I.P.

Abstract

According to the requirements of the technical regulations, all protective devices of tractor units are subject to obligatory certification. One of the main protection frame of the operator when overturning is the ROPS system. According to the requirements of State standard (GOST), the test for a compliance with protective structures ROPS should be carried out on the basis of full-scale tests. The aim of the investigation was to develop the experimental procedure and to obtain the result of the assessment of the compliance with the safety requirements of the ROPS safety device of the bulldozer compartment B10 (B12) manufactured by the Chelyabinsk Tractor Plant. The tests were carried out at the Ural Test Center NATI. For this purpose, a special stand was used, allowing to test the protective cabs of tractors with a total mass of up to 110 tons. For this purpose, a special test bench was used, allowing to test the protective cabs of tractors with a total mass up to 110 tons. The hydraulic system of the test bench allowed to carry out the process of lateral loading ROPS step by step, where each step corresponded to the deformation of the construction 10 mm. At each step, the acting forces and deformation of the construction were registered. The accumulated energy of the construction was calculated as the area under the stress-strain curve. The required GOST force Fy = 212,4 kN was achieved with a deformation of 180 mm. However, the lack of the accumulated energy at that time required a continuation of the lateral loading of the construction. The required energy according to GOST U = 40867 J was collected during the lateral deformation ∆ = 270 mm. The force at that was Fy = 243. After removing the lateral load, the construction was subjected to vertical static and longitudinal loading. During the whole experiment of the protective device ROPS repair, correction of deformations and bringing the construction into order were not allowed. The results of tests of the ROPS cab construction of bulldozer B10 (B12) have showed the compliance with the GOST safety requirements. During the ROPS deformation, the penetration of the elements of the protective construction into the zone of a limited volume of the driver's seat was not observed.
Tractors and Agricultural Machinery. 2018;85(3):68-72
pages 68-72 views

The investigation of thinning of a layer of the long-fibred flax stems in a channel with adjustable cross-section

Romanov V.A., Novikov E.H., Bezbabchenko A.V.

Abstract

The rise in the proportion of long fiber in the commodity output of the primary processing enterprises of the fiber flax is an important task, the solution of which is necessary to increase the efficiency of the flax growing. More than half of the losses of long fiber cause a poor quality of preparation of a layer of flax retting to the processing. The technological processes of the existing layer preparation technology can not be adapted to the changed raw material parameters for the roll-up harvesting of the flax. In this regard, the urgency of the development of individual processes and a new technology in general for the preparation of a layer fed to the milling machine of the production line. The main technological process of layer preparation is its thinning. The linear density of the initial layer varies widely. To bring it to a technologically rational value, the equipment must provide a regulation of the coefficient of thinning. It is possible to provide this by using a thinning channel with adjustable cross-section. For its justification in the investigations the aim has been set to determine the influence of the structural and technological factors on the coefficient of thinning of the layer of flax. The investigations were carried out using active experiments on the prototype of this type of thinning channel created in VNIIML. The independent factors were: the linear density of the initial layer; linear velocity of the layer at the output from the thinning channel; height of the channel at the input and output from it. Two versions of the channel implementation are used: from one type of toothed discs with a number of teeth of 40 pieces.; combined - from two types of discs in equal proportion to the number of teeth 40 and 48 pcs. A significant influence on the thinning coefficient of the channel height layer at the input and output, as well as the linear density of the initial layer is determined. The possibility of adjusting the coefficient of thinning the layer by changing the cross-section of the thinning channel. It is established that the number of teeth on the thinning disks and the structure of the thinning channel exert a significant influence on the process of thinning the layer in the channels with free fixation of the stems. Mathematical models that adequately describe the influence on the coefficient of thinning of the investigated factors are presented. Conclusions are formulated about rational parameters of the thinning channel with a controlled cross-section and the expediency of its application for the thinning of the layer of flax.
Tractors and Agricultural Machinery. 2018;85(3):73-78
pages 73-78 views

The results determine the acceleration and the mass of the tractor MTZ-80

Arzhenovskiy A.G., Asaturyan S.V., Dagldiyan A.A., Kozlov D.S., Shchus E.R.

Abstract

The performance of machine-tractor units depends on many factors and production conditions, and primarily on the energy intensity of the process. The main indicator of the energy intensity of the process is the traction resistance of the aggregated agricultural machine. The absence of a simple and reliable method for determining this indicator leads to the heterogeneity of the devices used, often manufactured on their own, and this entails different reliability of the results. Therefore, the development of methods and means of determining the traction resistance of agricultural machines, acceptable not only for testing stations, but also for specific farms, is very relevant and of considerable interest. In this paper, we propose an operational method for determining the traction resistance of mounted agricultural machines, based on the analysis of parameters of transient acceleration modes of machine-tractor units with an instantaneous increase in fuel flow. The aim of the work is to develop and complete the measuring and computing complex, as well as to conduct experimental studies to determine the values of acceleration of the tractor and its reduced weight on one of the increased gears, allowing to implement this method of determining the resistance of agricultural machines. For the realization of left targets was developed and assembled measuring and computing complex determine the dynamic characteristics of machine-tractor units, through which with the aid of patented techniques on the base station «Kislyakovskaya» Kushchevskaya district of Krasnodar region was carried out experimental studies to determine the acceleration values of the tractor MTZ-80 and its given mass in one of the elevated gear. The obtained results allow to implement the proposed method for determining the traction resistance of agricultural machinery.
Tractors and Agricultural Machinery. 2018;85(3):79-86
pages 79-86 views

Improvement of service properties of L53 steel with thermal strengthening

Mihal'chenkov A.M., Budko S.I., YUreva A.A.

Abstract

The production of domestic all-metal plowshares made of steel L53, in the current situation in the agriculture, requires new solutions aimed at increasing the resource without significant technological and economic costs. Potential opportunities in this respect lie in conducting the thermal strengthening of such steel. However, the well-known works on this issue do not give a definitive answer about the possibilities of L53 and the optimum mode of heat treatment in terms of ensuring abrasive wear resistance. Therefore, the aim of the presented investigations was to improve the service properties of steel L53 by thermal strengthening, expressed in increasing hardness and wear resistance. During the experiments, the experimental samples (steel L53) were subjected to heating from 720…870 °С within 20 °С and cooling in the water with the subsequent determination of hardness and abrasion resistance. The wear tests were implemented on the plant of its own design, which allows changing the experimental conditions within a wide range. The obtained results indicate that conducting thermal strengthening from temperatures 840…860 °С allows increasing the abrasive wear resistance of L53 steel by 2,5…3 times, which is connected with phase transformations and the formation of hardening structures. It has determined by the experiments that the rational parameters of the thermal strengthening regime, which make it possible to exclude such an additional operation as the abatement. Accordingly, the application of thermal strengthening to provide increased hardness and resistance to abrasive enviroment (especially with regard to plowshares) is a necessary technological operation in the production of parts of tillage tools made of steel L53.
Tractors and Agricultural Machinery. 2018;85(3):87-91
pages 87-91 views


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