Traktory i sel hozmashiny

The paper presents a comprehensive review of current trends and challenges related to the development of hybrid power units (HPU) in the transport industry. The paper discusses the main types of hybrid systems for wheeled and tracked vehicles, features of their architectures and principles of operation, with a focus on technical, environmental and economic aspects. Particular attention is paid to the analysis of battery technologies, energy management systems, and recycling issues. The authors emphasize the key challenges of the industry: battery degradation, high component costs, dependence on climatic conditions, and others. The review also contains a comparative analysis of solutions from the world’s leading manufacturers. In addition, promising trends are discussed, including the development of solid-state batteries, the introduction of artificial intelligence, and the development of wireless charging. Special attention is paid to analyzing the value chain of hybrid power units. The uniqueness of this review lies in the systematic approach to analyzing the HPU market, combining technical, economic and regulatory perspectives. The paper can be useful for both transportation and energy professionals and researchers involved in sustainable development and implementation of innovative technologies in the transport sector.

BACKGROUND: Plant processing methods used for the preparation of feed for farm animals should ensure maximum preservation of their nutritional value and beneficial properties.

AIM: Modification of the design and justification of the operating modes of the mowers' flattening device to improve the quality of harvested grass feed by increasing the feed value and reducing mechanical losses.

METHODS: The research objects are a mower with devices for grass flattening and processing with an adhesive-nutrient, a centrifugal-type cutting mechanism, a flattening device with two ribbed rollers. The main condition for the stable operation of the roller device is ensuring the capture of stems by rollers without pile-up and clogging.

RESULTS: According to the research results, it was found that the process of evaporation of moisture from the grass is accelerated by removing the surface (cuticle) layer from the stems, and torn leaves, inflorescences and torn parts of the stems are glued with a liquid adhesive-nutrient having a feed value. After hardening, the adhesive-nutrient increases the stiffness of the stems, forming an easily ventilated structure, which accelerates the drying of herbs, mechanical losses are eliminated.

CONCLUSION: The proposed design of the mower improves the quality of harvested feed, as the time for its drying is reduced, and the adhesive introduced increases the feed value, the loss of leaf and fine-grained parts of plants is reduced.

BACKGROUND: Due to the significant increase in the number of vehicle on-board consumers, the requirements for power supply systems of vehicles are increasing every year, in particular, for alternators with various excitation systems, the main indicators of which are the quality of the rectified voltage, the value of the rated current, weight and size indicators, reliability, noise level and service life.

AIM: To present a method for calculating the magnetic circuit of switch reluctance machines in the ANSYS Maxwell software.

METHODS: The calculation was carried out in the ANSYS Maxwell software and computing complex.

RESULTS: The calculation of the main parameters of switch reluctance generators is carried out according to the well-known method. However, such calculation methods have a high error in the output indicators and do not consider the coefficients of loss and saturation from permanent magnets, which is an important feature of the magnetic circuit of some inductor alternator designs. Therefore, the ANSYS Maxwell software, which allows simulating electromagnetic processes inside the generator in more detail, is used for modeling.

CONCLUSION: The finite element model of the inductor alternator allows optimizing the object under study and increasing the specific power, with constant weight and size indicators. Based on the simulation results, the following curves are built: voltage, current, frequency, shaft torque, magnetic induction, loss coefficient, etc. The results obtained allow analyzing the finite element model of the alternator in detail and giving recommendations to enterprises on the design of switch reluctance alternators for mobile units of various purposes.

BACKGROUND: The research solves the problem of validating the spatial motion multibody dynamic model of a complete highway road train with spring cabin truck in order to prove its applicability as a tool for analyzing and evaluating the vehicle operational properties and researching their improvement methods.

AIM: Conducting a set of highway road train field tests to obtain experimental data on vibration acceleration processes in a truck cabin with suspension followed by an its operational properties analysis and evaluation according to the comfort criteria, and conducting a results-based validation procedure for the spatial motion multibody dynamic model of a complete highway road train developed as a toolkit for vehicle virtual testing.

METHODS: The work uses methods of experimental research of a real highway ground vehicle at the road surface using measuring equipment in order to obtain experimental data for analyzing the highway road train dynamics operational parameters.

RESULTS: The experimental data obtained in the form of vibration acceleration processes in the sprung truck cab form the validation basis of the research and are used during the vehicle motion model validation procedure to compare and determine whether the behavior of the highway road train dynamics model corresponds to the real world in the claimed field of application.

CONCLUSION: According to the results of the vehicle spatial motion simulation model validation, which was the aim of this study, it is found that the normalized RMS errors of the simulation characteristics according to the “comfort” criterion are less than 10%, which corresponds to measurement errors for analyzing vibration load and vehicle comfort and indicates the research objective achievement. The multibody model of a highway road train can be used as a tool for analyzing the vehicle comfort, as well as for evaluating the effectiveness and operability of methods for improving comfort in cargo ground vehicles and the vibration-insulating properties of their suspension systems according to comfort criteria with an error of less than 10%.

BACKGROUND: When preparing flax straw using the dew retting method, uniformity of the raw material’s technological parameters along the length of the stems is not ensured, which reduces the yield and quality of the fiber. The excessive spread of values is due to differences in the mechanical properties of the stems along the length of freshly pulled plants. The middle and upper parts of the plant, when in contact with the working parts of flax harvesting machines, receive microdamage to their structure and dry out faster, activating tissue maceration in these areas of the stem. The lower part of the plants, having no such contacts, retains the integrity of their structure and remains viable, delaying the maturation process in this zone and increasing the non-uniformity of the parameters along the stem length. Maximum non-uniformity is observed during two-phase flax harvesting due to a long gap between the effects of the working parts on individual sections of the stems. The most effective solution to the problem is flattening the lower part of the plants when flax pulling. Many known scientific studies confirm the high efficiency of this technique. At the same time, flattening weakens the bending stiffness of the stems, which can complicate layer formation before flax straw processing and reduce the yield of long fiber.

AIM: Study of the effect of flattening working bodies of flax harvesters on the bending stiffness of plants.

METHODS: To study the influence of operation modes of flattening working bodies of flax harvesters on bending stiffness in consequent cross-sections of stems along the whole technological length of plants harvested using the two-phase technology with flattening of root ends at flax pulling, the TLP-1.5K (P) flax pulling machine with a two-roll flattening unit and the POL-1.5K gathering-and-combing machine with a comb stripping unit were used. A special device capable of estimating the bending stiffness of the stem by measuring the fracture force and the corresponding deflection has been developed. Conventional and partial methods of experiment conducting were used.

RESULTS: It has been found that stems flattening during two-phase harvesting does not have a significant effect on the distribution of bending stiffness along the technical length of the plant. In all cases, the weakest part of the flattened stem is its middle part, flattened by the belts of the pulling sections. Therefore, the maximum probability of stems bending during layer formation is observed in the middle part, and the processes of thinning of the layer of flattened and non-flattened stems will not have significant differences. Processing of experimental lots of flax straw obtained during two-phase flax harvesting with flattening of the root ends of plants showed an increase in the yield of long fiber by an average of 2.37%. Thus, the categorical hypothesis about the harmful effect of plant flattening on the process of layer thinning and the yield of long fiber was not confirmed.

CONCLUSION: To ensure high efficiency of the two-phase technology of flax harvesting, all machines intended for plants pulling should be equipped with flattening units. In addition, it has been found that it is necessary to process the tops of the stems with crushing rollers as well.

BACKGROUND: One of the main requirements for modern production systems is ensuring high competitiveness of the manufactured product. In order to achieve this, it is necessary to ensure the number of indicators of product quality: low selling price, high service performance, reduced delivery times, etc. A promising direction in this case is the use of materials with special properties for the manufacture of functional parts of machines such as drilling pumps considered in this paper.

This scientific paper is devoted to the issues of definition of processing methods that ensure the required parameters of surface quality and increasing productivity. A distinctive feature is that a material with special properties such as the inverse nature of the hardness distribution is considered. This feature makes it possible to increase the efficiency and stability of production simultaneously.

AIM: Determination of conditions that ensure simultaneous increase of efficiency and stability of production of drill pump sleeves made of the material with special properties.

METHODS: Theoretical research was based on the planning and organization of the experiment, quality management methods, similarity theory, signal processing. Experimental research was done on a numerically controlled lathe. Boring cutters with mechanical attachment of plates are used as cutting tools. The vibration signal was recorded using an accelerometer sensor. Roughness was measured with a profilometer. The obtained results were processed using both standard and original software.

RESULTS: Based on the studies performed, conditions were identified under which the required surface quality parameters of the cylinder sleeves of drill pumps made of material with special properties are ensured. As a result of analysis of vibration signals, areas of vibration stability were determined, which makes it possible to stably obtain output parameters of manufactured products. Reasonable values of longitudinal feed are determined by criteria of surface quality and stability of oscillatory processes. Using the similarity theory, the cutting rate, which provides an increase in the production efficiency of drilling pump bushings due to the achievement of reasonable productivity, was calculated. The obtained results are drawn up in the form of maps of rational processing methods, which can serve as reference material for existing industries.

CONCLUSION: Studies have shown that this hypothesis has been confirmed, and the use of materials with inverse hardness distribution makes it possible to increase the efficiency and stability of the production of cylinder sleeves of drill pumps while ensuring the required surface quality parameters.

BACKGROUND: The use of universal energy units (UEU) in agricultural production is quite limited, despite their technological capabilities.

AIM: Study of the technological capabilities of UEUs, the features of their operation, comparative analysis of the operational properties of UEUs coupled to a semi-mounted forage harvester with other forage harvesters.

METHODS: In accordance with the research method, studies were conducted to optimize the operation of the harvesting and transport facility (HTF), “field” and theoretical studies were conducted. Basis of the “field” studies was the statistical data characterizing the operation of the HTF, and basis of the theoretical studies was elements of probability theory. Based on the results of the previously conducted studies, it was assumed that motion velocity of the chopped mass in the technological path of a forage harvester defines variation of the cargo bulk weight in the vehicle body, which in turn has a significant impact on the vehicles’ performance capacity.

RESULTS: The theoretical dependence of the bulk weight of the harvested crop in the vehicle body on the motion velocity in the technological path of a forage harvester is derived. It is found that with an increase in the motion velocity, the bulk weight of the harvested crop in the vehicle body increases: during free fall, the bulk weight is 0.250 t/m³ at a free fall velocity of about 5–6 m/s (KSS-2.6), and 0.443 t/m³ at a free fall velocity of 57.6 m/s (UES-280 + KPK-3000.

CONCLUSION: The use of mathematical dependencies allows quick determination the yield rate of the harvested agricultural crop. According to the yield rate, it is possible to determine the optimal number of vehicles required to ensure non-stop operation of forage harvesters, i.e. to quickly manage the work of the harvesting and transport facility taking into account the forage harvester used, the distance from the field to the storage location. The results of the study can be used in practical work in any region of Russia.