Agricultural machinery and technologies (E-Journal) / Сельскохозяйственные машины и технологии
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УСОВЕРШЕНСТВОВАННАЯ ТЕХНОЛОГИЯ УБОРКИ ХЛОПКА-СЫРЦА
Get PDFOfficially approved machine technology of raw cotton harvesting in the modern conditions of agricultural production in the Republic of Uzbekistan does not make possible to mechanize in maximum this process with receiving qualitative cotton in a short time. A harvesting technology is effective, if more than 85 percent of cotton bolls are opened, and cotton-picker makes two passes. Thus, the second pass is carried out right after the first, but in an opposite direction. The authors presented results of field experiments, drew practical conclusions. The developed technology of picking, which basis the patent RUZ is, considers new forms of managing. Farms received practical recommendations about picking row cotton with necessary quality in a short time. In general they will be acceptable and for other cotton republics, next to Uzbekistan (Kazakhstan, Turkmenistan, Tajikistan, Azerbaijan).Официально утвержденная машинная технология уборки урожая хлопка-сырца в современных условиях сельхозпроизводства Республики Узбекистан не позволяет максимально механизировать этот процесс с получением качественного хлопка в сжатые сроки. Показали эффективность технологии уборки, осуществляемой при раскрытии 85 и более процентов хлопковых коробочек за два заезда хлопкоуборочной машины. При этом второй заезд осуществляется сразу вслед за первым, но в противоположном направлении. Представили результаты полевых опытов, сделали практические выводы. Разработанная технология уборки, в основу которой положен патент РУз, учитывает новые формы хозяйствования. Фермерские хозяйства получили практические рекомендации по сбору выращенного урожая необходимого качества в сжатые сроки. В целом они будут приемлемы и для других, соседних с Узбекистаном, хлопкосеющих республик (Казахстана, Туркменистана, Таджикистана, Азербайджана)
Исследование и разработка материалопровода измельчителя барабанного типа
Get PDFFodder and straw harvesting units are equiped with material feeder of various designs which are applied for mass transportation from shredder. Transportation is carried out owing to action of centrifugal forces of the crushing drum and the air stream created by it. Thus, loss of the shredded mass on the way from a material feeder to the vehicle reach 15 percent. The main reason for the specified losses is blowing of mass particles from the air stream. A louver attachment of a new design decreases air stream intensity. The authors revealed possibility of losses reduction by the theoretical analysis and physical modeling of process of the air stream movement. Quasi-homogeneous substance inside a material feeder consists of the shredded straw and air which have density and pressure average on time and on canal section. To decrease air stream intensity the authors used the continuity and momentum equations. Thus, change of a substance mass expense or its density and speed was considered. This change was caused by separation of clean air. Tests of the developed material feeder showed that losses of the shredded straw were reduced by 40 percent. Thus a louver baffle fitted to the end of a material feeder decreased losses by 9 percent
Ресурсосберегающие машинные технологии и режимы работы кукурузоуборочных машин
Get PDFRussian agrarian can increase corn production and not depend on import if they get more yield and reduce losses at all stages of a harvest cycle. A unified complex of modern highly effective, resource-saving technologies and technical means of harvesting and postharvest processing of corn is for this purpose necessary. The authors offered a concept of multilevel system approach to interconnected functioning of all subsystems of corn production (from harvesting to crop processing and storage) by criterion of resource-saving. Resource-saving technologies of harvesting of ear corn with thresh in a field and with getting of corn and corn cob mix. The minimum of cumulative expenses of energy when harvesting ear corn (1005.3 megajoule per tonne) is provided by technology with use of a self-propelled picker-husker. For harvesting with ear corn thresh in the field the rational technology (724.4 megajoule per tonne) includes harvesting by the combine with an axial and rotor threshing mechanism on the basis of new constructive and technological decisions. The most effective technology is corn harvesting with use on a forage corn and corn cob mix (638.5 megajoule per tonne). The authors developed a block scheme and mathematical model of optimization of parameters and operating modes of technical means. As a result of optimization modernization of the corn harvester provided decrease in energy consumption from 260.4 to 228.2 megajoule per tonne, or by 12.4 percent; increase of combine capacity from 3.4 to 4.6 ha/h, or by 1,4 times, improvement of grain output акщь 12.3 to 14.7 kg/s, or by 1.2 times. Optimum parameters of the unit: width of capture of a harvester made 8.4 m, the working speed of the movement - 6,6 km/h, the mass of the combine - 18180 kg, engine capacity - 224.8 kW, optimum terms of harvesting of grain corn - 8 days
ИССЛЕДОВАНИЯ ПОВОРАЧИВАЕМОСТИ ТРАКТОРА ДЛЯ ПОСТРОЕНИЯ ГИБРИДНОЙ ТЕОРИИ ПОВОРОТА
Get PDFTurn is one of the main and functionally difficult types of the movement of the wheel mobile traction and transportation vehicles (TTV): cars, tractors, self-propelled chassis, all-terrain vehicles. Settlement and experimental questions of kinematics of TTV turn are considered, settlement schemes of turn of all-wheel drive running system are chosen, models of kinematic wheel slip are created. Turn of a tractor without and with traction loading at the switched-off and switched on gear sistem of driving axle is experimentally investigated. Results of settlement pilot studies and the received mathematical models of turn of the machine make it possible to increase the accuracy of the set trajectory of the movement and to make adjustments of the machine and tractor unit movement, to reduce turn radius. At circular turn with traction load of 12 kN speeds center moving back behind driving axle of a tractor with the interaxal blocked drive equals 2.9 m, and coefficient of a kinematic discrepancy is 1.05 while with the interaxal differentiated drive these sizes are equal 1.03 and 0.93 respectively. Thus radiuses of turn of tractors with various drives differ insignificantly: 6.5 and 6.7 respectively. It is noted that at TTV on shell tires without traction loading the longitudinal coordinate of the speeds center is displaced from an axis of wheels rotation by 0.15 m back, side slip angle of forward wheels moving equals plus of 5.0 and plus of 7.8 degrees, kinematic wheel slips come nearer to 0. At circular turn with traction loading the speeds center moving back behind an axis of the back driving axle makes minus of 1.8 m and minus of 0.9 m, angles of kinematic moving within 5-10 degrees; angles of side moving are equal minus 5 and minus 7 degrees
Моделирование аэродинамики факельновихревого режима в топке для растительных отходов
Get PDFAt operation of fire chambers it is necessary to control amount of the air spent when fuel burning. For for this purpose scientist investigate aerodynamics of a fire chamber. On cold model we studied aerodynamic parameters of a fire chamber for plant materials, including three options of the organization of secondary blasting: from fuel input, from the opposite side and from both parties. Their influence on stability of ignition and burning of fuel was revealed. Conditions of formation of vortex circulating contours, their quantity at various giving of air in model, intensity of their rotation and dependence of an arrangement of contours from consumed concentration amount were established. As model bodies we used real objects of burning: sunflower hull and straw shreddings. As criteria of optimization of burning were degree of fullness of the chamber with a material rotating in circulating cameras and vortex rotation intensity. The minimum speed of the air given to model as primary, secondary and tertiary blasting, was limited by a constraint of not drop-out of particles from vortexes. Optimization of a given air consumption is caused by decrease in coefficient of surplus when burning (1.2-1.5). The optimum structure of a two-phase blast provides one or two circulating vortexes in the camera of model with a speed of rotation of 4; 6 and 8 meters per second at consumed concentration of 0.2-0.3 kg of material per 1 kg of air. The maximum filling of the camera and the minimum loss of particles from vortex correspond to such parameters
Направления ресурсосбережения в базовой сельхозтехнике
Get PDFThe autors proved the directions of resource-saving with regard to basic agricultural machinery: combine harvesters and tractors of classes 3 and above. The analysis has shown advantages of track laying vehicles in interaction of technogenic processes with productional agroecosystems. These advantages provide to track laying vehicles high technological need for agrarian and industrial complex in comparison with wheel machines. One of options of completing of the machine and tractor units (MTU) is use of multioperational trailing implements and a continuously variable ratio hydraulic drive of a undercarriage. To provide a turn of MTU with the minimum size of a rotary strip it is necessary to use mounted equipment more widely. The authors offered to equip tractors with two (forward and back) separate power takeoff shafts. The model of new generation of mobile power means MES-5300 with two mounted soil-cultivating implements on forward and back mounted systems, and also model with the mounted fodder harvesting adapter and the trailed implement on back mounted system is developed for soil preparation for winter wheat sowing. Due to the special technique it is possible to determinate technical and economic efficiency of the new design machines. If parameters of new machine by 1.2-1.3 times exceed the characteristic existing (basic) one, then we talk about usual modernization; excess by 1.5-1.8 times indicates deep modernization. And advantage by 1.8-2.3 times allows to refer new design to a class of innovative machines. The number of the integrated operations when using multioperational equipment on the basis of MES of the fifth generation is equal 17, when using modern technology on the basis of a tractor of the fourth generation - 27. As result the general capacity of equipment of the fifth generation increases by 20 percent
К ВОПРОСУ ОБОСНОВАНИЯ ТЕХНИКО-ЭКОНОМИЧЕСКОГО УРОВНЯ СЕЛЬСКОХОЗЯЙСТВЕННЫХ МАШИН И ОБОРУДОВАНИЯ
Get PDFIn recent years, a large amount of technology and equipment of both domestic and foreign production for agriculture comes in Russia. However, neglected domestic printing techniques justification technical-and-economic level (TEL) used machinery and equipment is not given. The authors outline ways to improve efficiency of agricultural production with use of techno-economic indicators system aimed at machinery improving. TEL means the relative quantitative characteristic of the machines and the degree of improvement of its performance and economic indicators compared to the characteristics of the basic option. When carrying out researches the program and target principle, and also Bayesian approach in the conditions of use of small samples were applied. Absent the parametrical characteristic for the developed machines and equipment, as an indicator of technical and economic level serves the coefficient of completeness of information. It is determined taking account the list of indicators, their importance (ponderability), interpretation and the analysis of TEL that is necessary for development of recommendations for decision making. Use of a technique hypothesizes that the importance of single indicators relative to one characteristic is the same and is equal to one. As indicators have probabilistic character, the researcher should consider the values received in various conditions. TEL is the overall index of enhancement of the estimated machine or equipment and is calculated on the corresponding formulas and criteria. The technique allows to determine objectively TEL of the current and future machines and equipment, and the analysis of components gives the chance to reveal allowances of increase in efficiency of various technological means
Экспериментальные исследования массопереноса в зерновке при осциллирующей сушке зерна
Get PDFAt a continual heatsupply at the beginning of drying process intensity of a mass transfer from a caryopsis surface exceeds intensity of moisture supply from its center to a surface. Thus the moisture content gradient in the caryopsis increases more than a difference between equilibrium moisture content and surface one. In the course of drying intensity of a mass tranfer decreases because of predrying of surface layers, the gradient of moisture content decreases, the front of evaporation continuously goes deep, respectively, intensity of process decreases. The variable heatsupply when seeds and grains drying allows to intensify process at full preservation of their quality indicators. The aythors proved parameters of oscillating drying and studied a mass transfer in a caryopsis for three drying modes: without lying, with lying after the heating period and lying after the cooling period. They compared efficiency of the oscillating drying modes to the drying mode at a continual heatsupply. The mass transfer was studied in the course of drying, humidity of a caryopsis and its cover and kernel was defined. Regularities of a mass transfer are revealed, the optimum modes of oscillating drying are offered: (the proportion of the periods «heating - cooling» is equal 10:10 minutes, an 15 minutes lying after the period «heating»). Physical and mathematical models are offered. The equation for calculation of lying duration is received. It is recommended to use the oscillating mode of drying with lying which duration should be sufficient for moisture redistribution in the caryopsis that keeps quality of seeds and grain. The lying extends process of drying (by 5 percent for an lying warmed up grain and by 10 percent for not warmed up one) in comparison with the same mode without lying, but allows to lower specific costs of warmth by 20-25 percent. At the oscillating mode lying duration is expedient when moisture removal increases in direct ratio to time