Vol 89, No 3 (2022)

BACKGROUND: The most important task, that supported the formation of mechanized agriculture in the 1920–30s, was the creation of domestic tractor industry. The Stalingrad (Volgograd) Tractor Plant, being the flagship of this important industry for many years, played a fundamental role in its development.

AIMS: Justification of the relevance of the tractor industry creation within the process of the country industrialization. Analysis of the advantages of tracked tractors in comparison with wheeled tractors, justification of need for their mass production, determination of trends in the development of technical and operational characteristics of general purpose tracked tractors.

METHODS: Analysis of the evolution parameters of the design of tracked tractors, produced by Stalingrad (Volgograd) Tractor Plant throughout its operation years, analysis of technical specification of the ten highest performance tracked tractors, produced in different years by this enterprise.

RESULTS: It is found that the first tracked models were based on wheeled tractors, met the operation requirements in the soil and climate conditions of our country in the best way, as well as satisfied the need for the use of such machines for military purposes. The importance of using the energy saturation indicator as the main factor of the tractor performance at increased velocities is justified; the graph of behavior of this indicator, depending on production year, is given and trends of its further growth are noted.

CONCLUSIONS: The energy saturation of tracked tractors, produced by the plant for 55 years, has increased by 1.85 times, from 7.5 to 13.91 kW. The experience of Volgograd tractor manufacturers should be analyzed and used in order to identify patterns, trends and modern directions of the tractor technology development.

BACKGROUND: Decisions of the Council of the Eurasian Economic Commission No. 127 of October 29, 2021. and No. 89 dated 04/15/2022. amendments have been made to the Technical Regulations of the Customs Union “On the safety of agricultural and forestry tractors and trailers for them” (TR CU 031/2012).

AIMS: Analysis of modern requirements for the environmental indicators of agricultural tractors in the Customs Union.

METHOD: Analytical.

RESULTS: By the decision of the Council of the Eurasian Economic Commission (October 29, 2021.) amendments have been made to the Technical Regulations of the Customs Union 031/2012, which cover the issues as follows: clarification of the requirements for the emission of harmful substances with exhaust gases from diesel engines, installed on mentioned tractors; introduction (for the first time) of requirements for emissions of harmful substances to dual-fuel engines (i.e. on the gas-diesel process); clarification of similar requirements for spark-ignition engines, operating on gaseous fuel. Environmental requirements for diesel engines correspond to the European level of Stage IIA level for the period up to 09/01/2022 and to the Stage IIIA after the specified period. The requirements for dual-fuel and gas engines are in accordance with those, specified in the technical documentation, until 09/01/2022 and in accordance with those, specified in TR CU 031/2012, after this date.

CONCLUSIONS: Clarification in the Technical Regulations 031/2012 of the regulatory requirements for the emission level of agricultural tractors eliminates the ambiguity in understanding of these requirements.

The replacement of conventional fuel with gaseous fuel theoretically provides a reduction in the emission of harmful substances from the exhaust gases of engines.

The replacement of diesel fuel with natural gas (methane) allows, theoretically, to reduce the emission of carbon dioxide, considered as one of the gases, contributing to the greenhouse effect, by 15%.

In order to ensure the development of the russian economy in the context of sanctions, it is advisa-ble to cancel the coming into force the Stage IIIA level environmental standards for agricultural tractors from 09/01/2022, which is given in the TR CU 031/2012.

These changes concern relate, firstly, to the clarification of the requirements for the emission of harmful substances with exhaust gases from diesel engines installed on these tractors, and secondly, the introduction (for the first time) of the requirements for emissions of harmful substances to dual-fuel engines (i.e. on the gas-diesel process), and thirdly, clarification of similar requirements for spark ignition engines running on gas fuel. Fuel gas refers to compressed natural gas and liquefied petroleum gas. Environmental requirements for diesel engines for the period up to 09/01/2023. correspond to the European level of Stage II, and after the specified period – to the level of Stage IIIA. For dual-fuel and gas engines. requirements for emissions of harmful substances: until 09/01/2023 - in accordance with those specified in the technical documentation, and after the specified period – in accordance with those specified in TR CU 031/2012.

BACKGROUND: Engine and vehicle control systems must have means of objective control in the form of self-diagnosis. This is especially true for new designs and technologies for controlling a gasoline internal combustion engine, such as deactivating cylinders in partial load mode. The paper gives an assessment of the possibility of self-diagnosis of cylinder shutdown in an automobile crank-guide engine without connecting rods using artificial neural networks.

AIMS: Determination of the possibility of creating an artificial neural network that recognizes which cylinders are currently in operation and which are disabled, based on the nature of the change in the signals from the sensors installed on the engine mounts and independent on the crankshaft speed.

METHODS: The study considered artificial neural networks of the LSTM and BiLSTM topology. An engine simulation model made in Simulink was used in order to obtain sensor signals. The conducted numerical experiments made it possible to obtain data, which simulates the sensors readings, and to train artificial neural networks to determine the order numbers and quantity of deactivated cylinders. Numerical experiments were carried out on the basis of full-factorial design. Various designs of experiments were used for training and testing of artificial neural networks, which made it possible to test the network on data that differed from the training data significantly. Testing took place on a large number of random sequences of cylinder deactivation modes.

RESULTS: The obtained results show a high degree of recognition of the order numbers of deactivated cylinders just after several tens of degrees of the crankshaft rotation while switching to the corresponding mode. For the LSTM network, mode detection accuracy was above 99% in both the data sequence transfer mode and the data streaming mode. Accuracy of the BiLSTM topology was over 99.9% in the data sequence transfer mode, but significantly decreased in the data streaming mode.

CONCLUSIONS: The use of considered types of networks in engine and car control systems is promising.

BACKGROUND: Amid the tightening of the CO₂ emission requirements as well as high level of competition on the commercial truck market, the focus area of the internal combustion engine (ICE) development is as follows: high engine efficiency and fuel economy, minimization of internal losses and engine cycle optimization for all operation modes. Engine performance factors of modern 12–13-liter diesel engines, existing on the global market, are as follows: the minimal specific fuel consumption is 179–182 g/kWh, effective efficiency is 46–48%. Decreasing of mechanical losses is one of the features that made the achievement of such factors possible. The relevant issue for choosing the strategy of mechanical losses decreasing is formation of balance in losses distribution between main ICE groups of components. Moreover, considering the mechanical losses dependence on engine operating speed, engine cycle parameters and engine design features, it is important to determine the pattern of change in mechanical losses.

AIMS: Assessment of mechanical losses of modern diesel engine with high effective efficiency in an experimental way. Formation of mechanical losses balance.

METHODS: The study object is the 6ChN 13/15 inline six-cylinder diesel engine with the operation volume of 11.95 liters. The mechanical losses assessment was performed with the engine, propelled by a dynamometric machine on a testing facility with fully stabilized conditions, with the method of sequential disassemble of main groups of components.

RESULTS: Relevant data of mechanical losses level of the modern diesel engine with the distribution between main groups of components is obtained. Mechanical losses dependence on operation speed, oil and coolant liquid temperatures is formed.

CONCLUSIONS: Practical value of the study lies in assessment of contribution of each group of components in the total friction as well as in assessment of the degree of design and technological development of ICEs. According to the study results, areas of possible improvement of friction for each group of components and engine as a whole will be formed.

BACKGROUND: For the cultivation of agricultural crops, the technology of basic dump tillage is widely used. More than 40% of energy resources are spent on it, due to the traction resistance of the working bodies of general-purpose plows. The technological process of plowing with such bodies has not changed much historically. Pruning of the soil layer is carried out with a ploughshare, crumbling and turning are carried out with a blade, the stability of the movement of the body is provided by a landside plate. At the same time, the resistance of a landside plate accounts for up to 20% of the total component of the traction resistance of the plow body. To reduce the traction resistance, the plow body without a landside plate has been developed in the Saratov State Agrarian University.

AIMS: Determination of towing and operational characteristics of the PBS-5M ploughshare for coupling with drawbar category 3 tractors and operation on heavy loamy soils.

METHODS: The experiments were carried out on the field, cultivated with a disk harrow after winter barley harvesting, in Novokubansky district of Krasnodar Region. The 0–30 cm soil layer had moisture ranged from 16.4 to 19.7% and hardness ranged from 1.86 to 2.74 MPa. The mass of plant and crop residues on the site averaged 185 g/m², and the average height of weed plants was 10.8 cm.

RESULTS: The towing and operational characteristics of the plowing unit, consisting of a serial T-150K drawbar category 3 tractor and an experimental PBS-5M plow, have been determined. The experiments were carried out for two variants of the plow. The first variant has the five-body configuration of the plow with the working grip width of 2.83 m and the plowing depth of 22 cm. The second variant has the four-body configuration of the plow with the working grip width of 2.27 m and the plowing depth of 30 cm. The driving mode of the first variant of the T-150K+PBS-5M unit varied in the operating velocity range from 7.27 to 9.2 km/h, the driving mode of the second variant of the unit was with the operating velocity up to 5.72 km/h. The energy intensity of the five-body plow was determined, corresponding to the traction and power characteristics of a drawbar category 3 tractor with a small power reserve of 2.87%. The PBS-5M four-body plow requires the power, almost equal to the operational power of the T-150K tractor engine.

CONCLUSIONS: As a result of experimental studies of the T-150K+PBS-5M plowing unit when processing the field, cultivated with a disk harrow after winter barley harvesting, it was found that the plow can be coupled with tractors of drawbar category 3. The reasonable mode of operation of the plow with the five-body configuration is provided at the velocity of 7–8 km/h and the plowing depth of 21–22 cm. The output during the main operation time of the unit was 2.1–2.3 ha/h, the fuel consumption was 12.9–12.7 kg/ha. The specific energy consumption of the unit was 47.5–46.78 kWh/ha, and the specific energy consumption of the plow was 31.26–31.4 kWh/ha. The engine load with the track skidding of 6.9–9.7% was 78–86%. With increasing unit velocity and increasing plowing depth, the values of the specific energy consumption of the unit and the plow raise as well. In field studies, it was found that it is necessary to use the tractor of higher drawbar category in order to couple the plow for the velocity up to 10 km/h and the plowing depth up to 30 cm in these agrotechnical conditions.

BACKGROUND: Based on the analysis of the morphological features of fiber flax, authors focus on the technical part of the stem, which contains fiber. To improve the quality and for most complete isolation of this product, the process of tissue maceration should be stimulated by stem flattening.

AIMS: Search of methods and means of obtaining the maximum effect from the use of two-phase flax harvesting technology, by ensuring uniform flattening along the entire technical length of the stems, starting from the earliest stages of harvesting.

METHODS: It is noted that the greatest effect of flattening can be achieved with two-phase flax harvesting. However, all known methods and devices involve a time gap between the flattening of different parts of a plant, which leads to a delay in the onset of maceration in untreated parts of a stem, delaying harvesting and reducing the quality of the fiber. Therefore, stems should be flattened immediately along their entire technical length at the earliest stages simultaneously with the pulling of flax, without flattening only the remaining part of the total length of plants, on which seed pods are located.

RESULTS: It has been found that the size of the flattening zone in the plant ribbon is not constant. Therefore, in order to reduce the likelihood of damage to seed bolls by flattening rollers with maintaining the high accuracy of the implementation of the proposed method, it is necessary to place the upper edge of the flattening rollers at the level of the upper limit of the technical length of plants, to form a stem stand, uniform in height, with a compact area of seed bolls, reduce the galloping of flax harvesters when moving over irregularities of field surface and use such working bodies that provide the minimum longitudinal shift of the stems in the formed ribbon.

CONCLUSIONS: An analysis of the existing means of mechanization showed that preference should be given to the TLP-1.5K trailed flax puller, which is lighter and cheaper and should be equipped with a flattening machine, in order to implement the proposed method.

BACKGROUND: High infection rate of grain harvest, produced in Russia annually, by causative agents of fungal and bacterial diseases, causing significant quantitative losses of grain and decreasing of storage quality, revealed low efficiency of operation of chemical treatment, nowadays widely used in production for disinfection of grain and seeds. Therefore, development of electrophysical disinfection methods, which are environmentally friendly and effective against fungal and bacterial infections, as well as development of technical devices for their implementation is a relevant scientific and production problem.

AIMS: Development of method of choice and definition of reasonable parameters of alternating current generator and electromagnet of disinfectant device for grain and seeds.

METHODS: The study subjects are methods and conditions of generation of alternating magnetic fields in the operational volume of impact on grain seeds flow. The study method is analysis of laws of electromagnetism and adaptation of them to the process of definition of electromagnet parameters for the operational volume of the disinfectant device. The study materials include the adapted mathematical expressions of magnet winding parameters and the method of their use.

RESULTS: For the sake of implementation of the new method of grain and seeds disinfection from causative agents of fungal and bacterial diseases by alternating magnet field, two methods of choice and calculation of electromagnet, which is the key element of the disinfectant device, have been developed. The first method comes to reasonable use of properties of a chosen generator by means of definition of coil winding parameters, ensuring demanded field density. Coil dimensions and time of impact on seeds will determine the device performance for treated grain. In the second method, the capacity of material flow through operational chamber (in the electromagnet) is conditioned by operational needs. It determines the size, parameters and operational modes of chamber (the inductance coil), ensuring the field demand, enough for disinfection, that, in the end, defines the properties of the generator.

CONCLUSIONS: The suggested method makes it possible to accelerate the development of facilities for implementation of highly efficient, energy saving and environmentally friendly technology of low-frequency magnetic disinfection of grain and seeds and to incorporate it in agricultural production.