In order to increase the efficiency of using vehicles (VEH) in mining and quarrying conditions, it is necessary to improve the components of gas equipment (cryogenic tank, gas nozzles, fuel supply cryogenic tubes, etc.) for supplying liquefied natural gas to the engine, as well as storage of liquid methane in a cryogenic tank with a long service life. For this, it is necessary to consider the process of heat and mass transfer of liquefied natural gas in a two-phase liquid-gas medium, taking into account the phase transition in the closed volume of the cryogenic tank under consideration. The article presents a model of unsteady heat and mass transfer of a two-phase liquefied methane medium in a developed two-tank cryogenic tank using a Cartesian coordinate system with fractional control volumes in space. The experimental data confirm the efficiency of using a cryogenic tank on the VEH platform, in which the run on liquefied methane compared to standard fuels is tripled, the shelf life of liquefied gas in the proposed cryogenic tank is 2-2.5 times longer than in the standard one.

Digital methods for diagnosing the technical condition of equipment are considered. It has been established that the most important means of increasing the efficiency of the use of agricultural machinery is the in-place identification of the parameters of the technical condition of the machine without disassembling it by improving the methods of monitoring the quality of work through the introduction of modern digital technologies.

The development of tractor design is closely related to its technological updating, improving environmental performance and increasing usability. Study of this problem in a historical context shows the unity in approaches of various agricultural tractor manufacturers to tractor design aimed at increased productivity and reduced operation costs in accordance with the requirements for agronomic and environmental performance. The main task of the first-generation tractors was to develop traction for agricultural work with maximum productivity and cost-effectiveness. Solution of these problems required further development of the tractor theory and the idea of the processes quality, and ensured the optimization of design and performance. As a result, the designs of tractors from different manufacturers developed in the same direction. Modern tractors are equipped with electronically controlled turbocharged diesel engines and have systems reducing toxicity of the exhaust gases. Power transmission of the tractors is implemented either with a robotic gearbox without interrupting the power flow, or in a continuously variable format, which ensures a more optimized operating mode. While for small-traction-class tractors stepless power transmission is provided with a mechanical variable speed gear, the rest of the tractors require electronicallycontrolled hydromechanical transmissions. As the capacity of power stations grows and an extensive power grid based on renewable energy resources is developed, the demand for electric tractors is to be increased. Tractors with hybrid power plants are likely to be produced at the transitional stage of development. They have the advantages of controlling processes in the machine and tools, the ability to provide agricultural implements with electric power for carrying out their work processes and ensuring their active drive to develop traction as well.

Existing potato harvesters cause damage to marketable products as a result of the interaction of potato tubers with each other, with working bodies and soil clods, given the wide variety of soil and climatic conditions in which the harvesting process takes place. In addition, under homogeneous soil and climatic conditions within the same accounting area, there is a large deviation from the average values of the main physical soil constants—moisture and hardness. Field studies were carried out to determine the fractional composition of soil clods, size-mass parameters, as well as their physical and mechanical properties with the identification of the greatest force for their destruction. The article presents a methodology for conducting research to assess the influence of working bodies on the magnitude of the force impact on potato tubers and soil clods during harvesting, a methodology for assessing the dynamic destruction of soil clods. The results of comparative studies of the force impact of the working bodies of modern potato harvesters, which affect the destruction of soil clods, causing damage to potato tubers as a result of their interaction with soil clods are presented.

The natural gas usage as a vehicle fuel in the mining industry is one of the priority tasks of the state. The article pays special attention to the component composition of natural gas from the point of view of its thermal efficiency during combustion in the combustion chamber of a power plant on a heavy-duty vehicle in difficult quarry conditions. For this, domestic and foreign methods for determining the main indicator characterizing the knock resistance of fuel in the combustion process - the methane number - are considered. Improvement of technical and economic indicators will be carried out by changing the composition of the gas mixture based on methane to fit the design features of the gas power plant, the methane number will be the determining indicator. A theoretical analysis of the influence of the methane number on such engine parameters as the compression ratio and the maximum speed of the flame front propagation in the second phase of combustion in the engine cylinder, expressed through the angle of rotation of the crankshaft, is presented. Based on the results of theoretical and experimental studies, the dependences of the influence of the methane number on the efficiency of the working process of the engine and its external speed characteristic were obtained.

Мировые производители автомобилей стремятся повысить количество выпускаемой продукции, снизить ее себестоимость и трудоемкость изготовления. Выбор направлений исследований, конструкторско-технологических разработок в радиаторостроении представляет собой чрезвычайно важную и актуальную задачу, обусловленную с одной стороны массовостью производства радиаторов для тракторов и автомобилей, с другой – благоприятными перспективами развития этих взаимосвязанных отраслей. (Цель исследования) Обосновать теоретически и экспериментально использование на автомобилях и тракторах комбинированной системы охлаждения, содержащей как алюминиевые, так и полимерные водяные радиаторы и аналогично жидкостно-масляные теплообменники, созданные на основе системы параметров для комплексной оценки автотракторных теплообменников. (Материалы и методы) Выполнили стендовые испытания с использованием специальной аэродинамической трубы для исследования тепловых и аэродинамических характеристик опытного образца тракторного радиатора с полиуретановой сердцевиной. Определили после достижении установившегося режима работы установки опытные величины по контрольно-измерительным приборам. (Результаты и обсуждение) Провели измерения всех параметров обоих теплоносителей последовательно на каждом установившемся режиме работы стенда. Получили зависимости основных показателей (приведенная теплоотдача, аэродинамическое и гидравлическое сопротивления) работы теплообменника, приближенные к условиям эксплуатации транспортных средств. (Выводы) Опытный образец радиатора МТЗ-80 с полиуретановой сердцевиной имеет большие перспективы в качестве альтернативного радиатора будущего. Повышение теплоотдачи радиатора на 10-15 процентов возможно при помощи использования алюминиевого оребрения на поверхности полиуретановой пластины. Снижение гидродинамического сопротивления на 15-20 процентов достигается за счет увеличения диаметра пропускной способности капилляров в полиуретановой пластине и количества самих пластин в соте радиатора.