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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Qualidade na distribuiÃÃo longitudinal de sementes por semeadoras de precisÃo e fluxo contÃnuo nas condiÃÃes edafoclimÃticas do Cearà / Quality in the longitudinal distribution of seeds per seed drill and streaming at conditions of CearÃ

Rafaela Paula Melo 20 February 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / As semeadoras desempenham um papel importante para a agricultura, pois elas criam as condiÃÃes adequadas para que o processo de semeadura seja feito de maneira correta. Um dos fatores que contribuem para o sucesso no estabelecimento da cultura à a uniformidade de distribuiÃÃo e a profundidade de deposiÃÃo de sementes no sulco de semeadura, estes fatores asseguram a populaÃÃo adequada de plantas. à muito complicado determinar todos os pontos que influem nas operaÃÃes agrÃcolas, por isso as ferramentas de qualidades se apresentam como uma alternativa para garantir o desempenho adequado do processo em funÃÃo dos fatores crÃticos, neste sentido o Controle EstatÃstico Processo auxilia no controle da qualidade nas etapas do processo, principalmente nos processos repetitivos, pois visa garantir a estabilidade e a melhoria contÃnua do processo. Este trabalho teve como objetivo avaliar a profundidade e a uniformidade de distribuiÃÃo de sementes de milho e arroz em funÃÃo de duas velocidades teÃricas de deslocamento 4 e 7 km.h-1 para as semeadoras de precisÃo mecÃnica e pneumÃtica e as velocidade de 4 e 8 km.h-1 para a semeadora de fluxo contÃnuo. O experimento foi realizado na Ãrea experimental do Departamento de Engenharia AgrÃcola da Universidade Federal do CearÃ, Campus do Pici, Fortaleza, CearÃ. O solo onde foi realizado o experimento foi classificado como Argissolo Vermelho-amarelo. As semeadoras de precisÃo foram reguladas para o espaÃamento de 14 cm entre as sementes de milho e profundidade de 5 cm, jà a semeadora de fluxo contÃnuo foi regulada para obter a densidade de 80 g sementes de arroz/m e profundidade de 3 cm. Para as semeadoras de precisÃo e fluxo contÃnuo realizou-se o processo de semeadura numa distÃncia de 50 m de comprimento com sementes de milho (Zea mays L.) e arroz, respectivamente. Para as semeadoras de precisÃo intervalos de 1m foram tomados ao acaso para a avaliaÃÃo da distribuiÃÃo longitudinal, jà para a semeadora de fluxo contÃnuo a avaliaÃÃo da densidade de distribuiÃÃo da semeadora foi realizada conforme as recomendaÃÃes de Campos (1998). A profundidade de deposiÃÃo de sementes de milho e arroz foi realizada por meio do mÃtodo da escavaÃÃo manual. Os dados foram analisados atravÃs do Software Minitab â VersÃo 16. Com o aumento da velocidade de deslocamento houve diferenÃa segundo a metodologia de Kurachi et al. (1989) para o nÃmero de espaÃamentos aceitÃveis, jà que com o aumento da velocidade de deslocamento o nÃmero de espaÃamentos aceitÃveis diminuiu para ambas as semeadoras, mas nas anÃlises estatÃsticas nÃo houve diferenÃa entre as velocidades avaliadas e a velocidade de deslocamento nÃo apresentou influÃncia na profundidade de deposiÃÃo de sementes para a semeadora pneumÃtica. Para a semeadora de fluxo contÃnuo o aumento da velocidade influenciou na uniformidade de distribuiÃÃo e na profundidade das sementes de arroz. / The planters play an important role in agriculture because they create the right conditions for the seeding process is done correctly. One of the factors that contribute to successful crop establishment is the distribution uniformity and depth of deposition of seeds at sowing, these factors ensure adequate plant population. It is very difficult to determine all the points that influence agricultural operations, so the tools of qualities present themselves as an alternative to ensure proper performance of the process in terms of the critical factors in this sense the CEP assists in quality control in the process steps especially in repetitive processes, it aims to ensure stable and continuous process improvement. This study aimed to assess the depth and uniformity of seed corn and rice based on two theoretical speeds shift 4 and 7 km.h-1 for the precision seeders mechanical and pneumatic and speed of 4 km and 8 km . h-1 for seed drills. The experiment was conducted in the experimental area of the Department of Agricultural Engineering, Federal University of CearÃ, Campus do Pici, Fortaleza, CearÃ. The soil where the experiment was conducted was classified as Typic yellow. The precision sowing machines were set to a spacing of 14 cm between maize and depth of 5 cm, because the seed drills was adjusted to the density of rice seed 80 g / m depth of 3 cm. For the precision seeders and streaming held up the process of seeding a distance of 50 m in length with seed corn (Zea mays L.) and rice, respectively. For precision sowing intervals of 1 m were taken at random for assessing the longitudinal distribution, as for seed drills evaluating the distribution density of the seeding was performed according to the recommendations of Fields (1998). The depth of deposition of seeds of maize and rice was performed by the method of manual excavation. Data were analyzed using Minitab Software - Version 16. With the increase in travel speed difference was observed according to the method of Kurachi et al. (1989) for the number of acceptable spacing, since with increasing travel speed and number of acceptable spacing decreased for both seeders, but the statistical analysis there was no difference between the measured speeds and speed did not have any influence on depth deposition of seeds to the air seeder. For seed drills to increase speed influenced the distribution uniformity and depth of rice seeds.
2

Desenvolvimento e avaliação de maquina multifuncional conservacionista para a agricultura familiar / Design and evaluation of conservationist multifunction machine for small farms

Albiero, Daniel 15 August 2018 (has links)
Orientador: Antonio Jose da Silva Maciel / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-15T15:39:14Z (GMT). No. of bitstreams: 1 Albiero_Daniel_D.pdf: 5141700 bytes, checksum: 5427f7d285092270bb614f9a4cc75e96 (MD5) Previous issue date: 2010 / Resumo: A agricultura familiar tem papel de destaque no Agronegócio brasileiro, pois a maior parte dos alimentos consumidos pelo povo brasileiro é proveniente desta categoria de produtores rurais. Apesar disto em termos de mecanização agrícola tal importância não é reconhecida nem atendida, já que pouca pesquisa tem sido feita para atender às demandas, além de haver poucas indústrias que se interessem em explorar o mercado de equipamentos agrícolas deste setor. Este panorama subentende um sério problema de utilização de trabalho mecânico nas pequenas propriedades rurais que se traduz em uma defasagem muito grande entre as pequenas e grandes propriedades, principalmente em relação à eficiência do trabalho na produção o que perfaz um ciclo onde a agricultura familiar mal consegue produzir para sua própria subsistência. Assim ela perde a oportunidade de se inserir eficientemente nas grandes cadeias produtivas do Agronegócio Brasileiro. Supõe-se que dotando a agricultura familiar, com um sistema mecanizado que realize as operações de semeadura de forma eficiente e conservacionista é possível amenizar a questão da utilização de potência. O objetivo deste trabalho foi desenvolver, construir e avaliar uma máquina multifuncional de semeadura conservacionista em faixas para pequenas propriedades rurais, com alta tecnologia, simplicidade de operação e pouca manutenção. Foram construídos dois protótipos que realizaram testes em campo para a caracterização da nova máquina com dados relativos ao desempenho do equipamento, principalmente em relação à emergência de plântulas. Foi utilizada a cultura da soja para os testes, pois possui dados exaustivos sobre sistemas de plantio conservacionista (plantio direto), facilidade para montagem do experimento e principalmente pela extrema eficiência do mecanismo dosador selecionado em distribuir as sementes de soja. Foi realizado também um estudo da qualidade das operações pertinentes à nova máquina, assim como uma Análise do Modo de Falha e seus Efeitos (FMEA) para propor modificações que visam melhorar o projeto. Pelos resultados obtidos, a nova máquina de semeadura confirmou a hipótese do trabalho de que o desempenho em relação à emergência de plântulas é compatível ao plantio direto. As características operacionais foram adequadas às necessidades das pequenas propriedades rurais, já que a capacidade de campo da nova semeadora possibilita o trabalho por toda a área das pequenas propriedades (10 ha) em tempo hábil dentro do período de semeadura (45 dias) / Abstract: The small farms in Brazil have an important position in agro-business, because it is the greater food's producing. However agricultural mechanization is not considered nor assisted, therefore it there is little research for to assist the demands of small farmers, beyond of industries have not interest for this market. This scenery is a big problem in relation at the utilization of power, mainly because of low efficiency of job in production, that it generate a cycle where the small farms do not get to produce for yourself consumption, and so it lost the opportunity of itself insert in agro-business. It is believed that with a conservationist mechanized system for efficient seeding it is possible that the problem will be decreased. Therefore the subject this work was to design, to develop, to construct and to evaluate a conservationist multifunctional machine of seeding in strip till system for the small farms, with high technology, simplified operation and with little maintenance. They were constructed two prototypes that they accomplished the field tests for the characterization performance of equipment, mainly in relation with plant emerging. It was seeding the soybean therefore this crop has many data about no till system (conservationist system) and the seeder have good performance with this seed. It was done a study of operation quality and a Fail Mode and Effect Analysis (FMEA) for to propose optimal modifications in project. For the results the new machine confirmed the hypothesis that the plant emerging is equal with no till system. The characteristics of operation were appropriate at needs of small farms, therefore the Field capacity of machine allow to sow every area of small farms (10 ha) in time period appropriate (45 days) / Doutorado / Maquinas Agricolas / Doutor em Engenharia Agrícola
3

VERIFICAÇÃO DE TIPOS DE DOSADORES DE SEMENTES DE MILHO E SOJA NO NORTE DO PARANÁ / CHECKING TYPES OF CORN AND SOYBEANS SEED FEEDERS IN NORTHERN PARANÁ

Schmalz, Cassiano Ricardo 10 January 2014 (has links)
The first works with Precision Agriculture in Brazil started with greater intensity from the 2000s in order to know and correct soil fertility. After long years of public-private research generated a vast database of information demonstrating that activities like sowing has become an essential step. Thus, studies on the accuracy in the distribution of seeds and seed distribution in variable density and quality of sowing methods by coefficient of variation (CV) and accuracy rate (IP), have become important tools to increase productivity. To this end, we performed a case study of the performance of types of corn and soybeans seed feeders in northern Paraná, 02 models of pneumatic seeder and 05 mechanical models (honeycomb disc). The experiments conducted during 7 years in 61 different locations, by the technical department of Pioneer Seeds, quantified the losses from failures of seeds in the row. Pneumatic seeders present numerical and statistical superiority both in the soybean as corn. / Os primeiros trabalhos com Agricultura de Precisão iniciaram no Brasil com maior intensidade a partir da década de 2000 com o intuito de conhecer e corrigir a fertilidade do solo. Após longos anos de pesquisa público-privada geraram um vasto banco de informações demonstrando que atividades como a semeadura tornou-se uma etapa fundamental. Assim, estudos relativos à precisão na distribuição de sementes como a distribuição de sementes em densidade variável e qualidade da semeadura, pelos métodos de coeficiente de variação (C.V.) e índice de precisão (I.P.), tornaram-se importantes ferramentas para acréscimo da produtividade. Com este intuito, realizou-se um estudo de caso do desempenho de tipos de dosadores de sementes de milho e soja no norte do Paraná, sendo 02 modelos de semeadora pneumáticas e 05 de modelos mecânicos (disco alveolado). Os experimentos realizados durante 7 anos em 61 locais diferentes, pelo departamento técnico da Pioneer Sementes quantificaram as perdas decorrentes de falhas de sementes na linha de plantio. As semeadoras pneumáticas apresentam superioridade numérica e estatística tanto nas culturas da soja quanto do milho.
4

Sistema plantio direto: velocidade de semeadura e populações de plantas de milho

Cavichioli, Fábio Alexandre [UNESP] 17 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-17Bitstream added on 2014-06-13T20:10:43Z : No. of bitstreams: 1 cavichioli_fa_me_jabo.pdf: 648826 bytes, checksum: 1314e2ae2e955d65b475307ab209b59f (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A cultura do milho no Brasil tem importante papel sócio-econômico, pois desempenha uma função estratégica na cadeia produtiva. Para a indústria, o milho é uma matéria-prima que possibilita obtenção de subprodutos destinados a alimentação humana e animal. O presente trabalho teve como objetivo avaliar o desempenho operacional relacionando o efeito da velocidade de deslocamento de um conjunto trator-semeadora-adubadora combinado com três populações de plantas (número de sementes por metro) na demanda energética do conjunto, na quantificação das características agronômicas referente a cultura do milho e análises físicas e químicas do solo. O experimento foi implantado na área da Fazenda de Ensino, Pesquisa e Produção da UNESP/Jaboticabal, SP, o solo da área experimental é classificado como LATOSSOLO Vermelho eutroférrico típico, A moderado, textura argilosa. O experimento foi constituído de um esquema fatorial 2x3 conduzido sob delineamento experimental de blocos casualizados com tratamentos sob duas velocidades de deslocamento do conjunto trator-semeadora-adubadora (6,5 km h-1 e 4,5 km h-1), definidas em função da potência do trator a ser utilizado, e três populações de plantas de milho (55.000, 65.000 e 75.000 plantas ha-1), definidas em função do híbrido utilizado, com quatro repetições, perfazendo um total de 24 parcelas. Foram analisadas as variáveis referentes a demanda energética da operação de semeadura como: força e potência na barra de tração, consumo horário e operacional de combustível e capacidade de campo operacional. Variáveis referentes a cultura: número médio de dias para emergência das plântulas de milho, população inicial e final de plantas, altura de inserção da espiga viável, altura de plantas e diâmetro do colmo, número de fileiras, número de grãos na fileira e índice de espigas, produtividade de grãos... / The maize crop in Brazil has an important socioeconomic role that it plays a strategic role in the production chain for the industry, corn is a feedstock that allows obtaining products intended for human consumption and animal feed. This study aimed to evaluate the operational performance relating the effect of forward speed of a tractor-planter combined with three plant densities (number of seeds per meter) and the energy demand of the set, the quantification regarding agronomic corn and analysis physical and chemical of soil. The experiment was established in the area of Finance Education, Research and Production, UNESP / Jaboticabal, SP, the experimental area is classified as Typic Eutrudox, moderate, clayey. The experiment consisted of a 2x3 factorial conducted under randomized block design. treatments under two travel speeds of the tractor-planter (6.5 km h-1 and 4.5 km h-1), defined according to the power of the tractor to be used, and three plant populations of maize (55.000, 65.000 and 75.000 plants ha-1), defined depending on the hybrid used, with four replications, a total of 24 plots. We analyzed the variables of energy demand in the sowing operation such as strength and power at the drawbar, fuel consumption and fuel and operating performance in field operations. Variables related to culture: the average number of days to emergence of corn seedlings, initial and final population of plants, height of ear insertion viable, plant height and stem diameter, number of rows, number of grains in the row index and cob, yield and mass of cornstalks and weeds. The speed of movement influence on power, operational field capacity and fuel consumption, increasing these variables and consumption reducing operating this variable, the population of corn plants in the affected stem diameter, with the smallest population in the highest diameter The combination of higher speed of seeding... (Complete abstract click electronic access below)
5

Desempenho operacional de semeadora em função de mecanismos de corte, velocidade e solos, no sistema plantio direto do milho

Mahl, Denise [UNESP] 02 June 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-06-02Bitstream added on 2014-06-13T20:22:26Z : No. of bitstreams: 1 mahl_d_dr_botfca.pdf: 815471 bytes, checksum: be15fff752262a6a07097824be496849 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / The success of no tillage system is directly related to the selection and efficiency of the seeders components as well as of the suitability of the forward speed and soil and vegetable covering characteristics. This research was carried out in a corn (Zea mays L.) field aiming to evaluate the operational and energetic performance of a no-tillage seeder in two soil types with different vegetable covering and with different forward speeds, furrow opener and cut elements. The performance were evaluated through parameters of seeds longitudinal uniformity distribution, seeding depth, soil mobilized area, tractor and seeder tractive wheel slips, draw bar pull and power requirements, fuel consumption, plantules emergency, culture growing and productivity. The experiments were carried out in two different farms. One at Lageado Experimental Farm, which the soil is classified as Nitossolo Vermelho distroférrico covered with 7 t.ha-1 of dry matter of corn, lupine and weed residues. The other experiment was carried out at São Manuel Experimental Farm, wich soil is classified as Latossolo Vermelho covered with 20 t.ha-1 of dry matter of Brachiaria spp and corn residues. Both experiments designs were 2x3x3 factorial in randomized blocks with four replications. The factors examined were: two furrow opener mechanisms (doubledisk and chisel opener); three tractor-seeder forward speeds (5.5; 7.9 and 10.1 km.h-1); and three covering cut mechanisms (smoothly, fluted and notched cut disks). The soil type and vegetable coverage interfered in the global seeder 4 performance and their cut and furrow opener components. Comparing with the experiment carried in Botucatu, the experiment carried in São Manuel provided larger values of: seeding depth, tractor wheel slip, percentage of soil covering, draw bar pull and power requirements, hourly... (Complete abstract, click electronic access below)
6

Desempenho operacional de semeadora em função de mecanismos de corte, velocidade e solos, no sistema plantio direto do milho /

Mahl, Denise, 1976- January 2006 (has links)
Abstract: The success of no tillage system is directly related to the selection and efficiency of the seeders components as well as of the suitability of the forward speed and soil and vegetable covering characteristics. This research was carried out in a corn (Zea mays L.) field aiming to evaluate the operational and energetic performance of a no-tillage seeder in two soil types with different vegetable covering and with different forward speeds, furrow opener and cut elements. The performance were evaluated through parameters of seeds longitudinal uniformity distribution, seeding depth, soil mobilized area, tractor and seeder tractive wheel slips, draw bar pull and power requirements, fuel consumption, plantules emergency, culture growing and productivity. The experiments were carried out in two different farms. One at Lageado Experimental Farm, which the soil is classified as ‘Nitossolo Vermelho distroférrico’ covered with 7 t.ha-1 of dry matter of corn, lupine and weed residues. The other experiment was carried out at São Manuel Experimental Farm, wich soil is classified as ‘Latossolo Vermelho’ covered with 20 t.ha-1 of dry matter of Brachiaria spp and corn residues. Both experiments designs were 2x3x3 factorial in randomized blocks with four replications. The factors examined were: two furrow opener mechanisms (doubledisk and chisel opener); three tractor-seeder forward speeds (5.5; 7.9 and 10.1 km.h-1); and three covering cut mechanisms (smoothly, fluted and notched cut disks). The soil type and vegetable coverage interfered in the global seeder 4 performance and their cut and furrow opener components. Comparing with the experiment carried in Botucatu, the experiment carried in São Manuel provided larger values of: seeding depth, tractor wheel slip, percentage of soil covering, draw bar pull and power requirements, hourly... (Complete abstract, click electronic access below) / Orientador: Carlos Antonio Gamero / Coorientador: Sérgio Hugo Benez / Banca: Carlos Eduardo Angeli Furlani / Banca: Antonio Jose da Silva Maciel / Banca: Rubens Siqueira / Banca: Geraldo da Silva / Doutor
7

Modélisation et optimisation énergétique des organes d'un semoir pneumatique / Modeling and energy optimization of the operative parts of an air assisted drill

Yatskul, Andrii 04 May 2016 (has links)
Dans le contexte du développement d’une agriculture durable, il est nécessaire d’optimiser le coût énergétique des opérations agricoles tout en garantissant des temps de travaux courts ainsi que la qualité des opérations réalisées. Cette question concerne en particulier l’opération du semis qui est déterminante pour la qualité de la future récolte. Les semoirs de grande capacité et à haute productivité conçus aujourd’hui se doivent d’être compatibles avec cet ensemble de contraintes. L’enjeu essentiel de cette thèse est donc d’élaborer une méthodologie innovante et utilisant des outils de modélisation dans le but de réduire la consommation énergétique des matériels de semis. En suivant cette logique, nous avons étudié quatre aspects clef de la conception des semoirs pneumatiques : la manœuvrabilité des semoirs poly-articulés, l’établissement des conditions du transport pneumatique des semences et des engrais, l’optimisation des systèmes de répartition des semences ou des engrais, et enfin les aspects énergétiques du mode d’introduction des semences dans le circuit pneumatique. Chaque modélisation a été précédée par une phase expérimentale de détermination des phénomènes majoritaires influençant le processus étudié. Ensuite une modélisation du processus étudié, basée sur la simulation des effets du phénomène majoritaire identifié a pu être mise en œuvre et des conclusions, appuyées par des essais expérimentaux, proposées quant à la conception des semoirs pneumatiques. L’étude de la manœuvrabilité des ensembles poly articulés a démontré qu’il était possible de proposer et de tester un modèle explicatif de prédiction de trajectoires adapté aux engins agricoles. Cette approche ouvre la voie à l’optimisation et à de nouvelles méthodes d’automatisation de manœuvres complexes, notamment des demi-tours en bout de champ. Il est par ailleurs possible de démontrer qu’une trémie en position arrière permet de réaligner plus rapidement la barre de semis après une manœuvre. L’étude des conditions du transport pneumatique a montré notamment que l’établissement de conditions de transport correctes au niveau des sorties de la tête de distribution conditionne l’ensemble de la conception du circuit de distribution de la matière. L’étude des systèmes de répartition des semences a permis d’expliquer l’origine des principaux défauts de répartition observés et notamment l’importance de l’adéquation entre le coude et la conduite verticale qui précède la tête de répartition des semences. Ces résultats ont ouvert la voie à l’étude de la mise en place de systèmes d’anticipation et de correction de ces défauts. Enfin l’étude comparée de deux systèmes d’introduction de la matière dans un circuit pneumatique a montré que du point de vue énergétique les systèmes pressurisés sont plus intéressants que les systèmes injecteurs. / In the context of sustainable farming, the optimization of the energy costs of agricultural operations allows shorter working times and high quality of the agricultural operations. This question relates particularly to the seeding. This operation one is decisive for the quality of the future harvest. The modern high capacity seed drills must be compatible with all the constraints. The main goal of this PhD thesis is thus to develop an innovative methodology, integrating the modeling tools, in order to reduce the energy consumption of the heavy seeding equipment. Thus, we explored four key aspects concerning air seed drill design: maneuverability of poly-articulated seed drills; establishment of the pneumatic conveying conditions of seeds and fertilizers; seed distribution accuracy optimization, and finally the energy aspects of the air stream loading systems. Each modeling was preceded by a preliminary experimental phase, defying the majority phenomena influencing the studied process. The modeling of the studied process and the conclusions (supported by experimental trials) have been proposed for the design of air seed drills. The study of maneuverability of poly-articulated agricultural machines showed that it was possible to get and test an explanatory model of trajectory prediction adapted for agricultural machines. This approach opens the way for optimization and automation of complex operations, including U-turns on headlands. We showed that a towed behind storage hopper (air-cart) allows faster realignment of the coulter bar after maneuvers. The study of pneumatic conveying conditions showed that the establishment of the correct conveying conditions in the outlets after the dispensing head defines the entire design of the distribution system. The study of seed distribution systems explains that the origin of the low distribution accuracy is caused in particular by the elbow and the vertical pipe before the dispensing head. These results open the way for the development of anticipation systems and correction of these defects. Finally the comparative study of two air-stream loading systems has showed that from the energy point of view the pressurized systems are more interesting than the injectors systems. / В рамках концепции устойчивого развития, необходимо учитывать энергетический аспект, сохраняя при этом эффективность использования рабочего времени и качества выполнения сельскохозяйственных операций. Особенно, это касается операции посева, определяющей в наибольшей степени будущий урожай. Современные широкозахватные зерновые сеялки и посевные комплексы вписываются в рамки устойчивого сельского хозяйства. Главной целью данной диссертации является разработка действенной методики проектирования пневматических сеялок, применяя методы моделирования и оптимизации, с целью уменьшения энергопотребления. Таким образом, мы использовали причинно-следственный подход для энергетической оптимизации четырех определяющих параметров: маневренность многозвеньевых посевных машин, обоснования необходимых условий пневмотранспорта, оптимизация распределения посевного материала, и ввода материала в магистральный трубопровод. В дополнение, снижение энергопотребления не должно сказываться на качестве выполнения технологического процесса посева. Моделирование каждого процесса, является следствием длительной экспериментальной фазы, посвященной определению наиболее значимых факторов, для каждого отдельного явления. В результате моделирований, симуляций и анализа, были составлены практические рекомендации, для конструкторов пневматических сеялок. Изучение маневренных характеристик многозвеньевых агрегатов позволило предложить и испытать физическую модель, позволяющую предопределить траекторию движение каждого звена машинно-тракторного агрегата. Такой подход позволяет автоматизировать выполнение наиболее сложных маневров (например, разворотов в конце гона). Кроме всего было показано, что заднеприцепные бункера позволяют более быстрое выравнивание агрегата после разворота. Изучение условий пневмотранспорта, позволило установить оптимальные, с точки зрения энергосбережения, параметры пневмотранспорта на выходе из распределительной головки, что послужило исходными данными для расчета характеристик пневмотранспорта в целом. Исследование процесса распределения семян в распределительной головке вертикального типа, позволило определить причины неравномерного распределения семян между выходными трубопроводами, в частности влияние отвода и вертикального трубопровода. На основании полученных данных, было предложена система устройств, позволяющих избежать возникновения завалов в системе, при минимальных энергопотерях. Сравнительные исследования двух систем ввода материала в магистральный трубопровод, позволили заключить, что питатели с наддувом являются менее энергоемкими по сравнению с питателями эжекторного типа.

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