Desempenho operacional de colhedora de forragem com diferentes tamanhos de partículas com e sem o uso do processador

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Tractor perfomance as a function of speed and seeder s tire inflation pressure

O desempenho de tratores agrícolas em condições de campo resulta da interação entre pneu e rodado, influenciado pela velocidade de deslocamento. O objetivo deste trabalho foi avaliar o desempenho de um trator agrícola sob diferentes pressões de inflação dos pneus da semeadora (518, 483, and 414kPa) e em duas marchas que proporcionaram velocidades de 3,0 e 6,0km h-1. O experimento foi realizado no campus de Jaboticabal da Universidade Estadual Paulista (UNESP). O delineamento experimental utilizado foi fatorial inteiramente casualizado (3x2), com quatro repetições. A força de tração foi influenciada pela marcha e pela potência exigida; no entanto, a pressão de inflação do pneu da semeadora não alterou esses parâmetros. Além disso, o consumo de combustível foi influenciado apenas pela marcha do trator. O consumo de energia foi maior com o aumento da velocidade, ocasionada pela mudança de marcha. A velocidade de deslocamento foi maior para a pressão de 518kPa, em razão da menor patinagem da semeadora promovida por essa pressão. A patinagem do trator não foi alterada pelos fatores testados.

Diesel e biodiesel de murumuru e de soja: desempenho operacional de trator agrícola no preparo do solo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise de cenários para auxílio à tomada de decisão no plantio mecanizado de cana-de-açúcar

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Qualidade da operação na cultura da cana-de-açúcar utilizando cartas de controle

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Desempenho de colhedoras de cana-de-açúcar em função do perfil de carga do motor

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Consumo de combustível de um trator agrícola em função do tipo de soloe da pressão de inflação nos pneus utilizando o equipamento canteirador

Agricultural mechanization improved the efficiency of field operations by providing an increase in crop production. The intensified mechanization, however, has led to higher energy use mainly in the area of fuel consumption. The objective of this study was to compare the fuel consumption of tractors using two different tire pressures for two different types of soil during tillage with irrigated cotton in semi-arid regions. These tests were performed at the Maricopa Agricultural Center (MAC), an experimental farm belonging to The University of Arizona with a Case 4x2 TDA 88kW equipped with an autopilot system. The results showed lower fuel consumption using a tire pressure of 124 kPa on sandy clay loan soil.

Consumo de combustível de um trator agrícola no preparo do solo para a cultura do algodão irrigado em função da pressão de inflação nos pneus

Currently, the efficiency in field operations and the increased productivity of crops is only possible with the use of agricultural machinery and equipment. This intensification of mechanized activities in agriculture, however, led to higher energy costs on farms mainly in the fuel consumption of agricultural tractors. The objective was to compare the fuel consumption of a tractor on tillage operations for irrigated cotton in semi-arid region varying two tire inflation pressures. The tests were conducted in Maricopa Agricultural Center (MAC), an experimental farm belonging to The University of Arizona using a 4x2 TDA Case tractor equipped with a 88kw autopilot system. The results showed lower values in the hourly fuel consumption by using the minimum tire inflation pressure of 124 kPa for all tillage equipment used.

Avaliação do desempenho das máquinas agrícolas na implantação da cultura do girassol

The sunflower oleaginous is the fourth of recognized importance in the oil production and few studies related to agricultural operations adopted for this crop. The objective of the present work was to study the performance of agricultural machines in the conventional tillage and reduced in the plantation of the sunflower crop. The experiment was installed at the Experimental Farm of Lageado, belonging to the Faculty of Agricultural Sciences of UNESP, located in Botucatu-SP. It consisted of two types of tillage (conventional tillage-CC and reduced tillage-CR), with experimental design in randomized blocks and four replications. The treatment CC promoted less coverage of the soil surface protected with waste when compared to CR treatment. The chisel plow was the tillage of equipment that required the tractor higher average traction force, average power traction and slippage, consequently, promoted lower average speed of work. The theoretical field capacity and area of land involved in the treatment CR were superior when compared to treatment CC, thereby lower consumption of fuel per hour worked was lower in CR treatment.

Demanda energética de máquinas agrícolas na implantação da cultura do sorgo forrageiro

Forage sorghum can be grown in areas and environmental conditions dry and warm, where the productivity of other forage plants can often be uneconomical. The soil disturbance can be made only on the lines of planting (direct seeding) or entirely from the area for seeding (conventional tillage), as plowing, harrowing, subsoiling and chiseling (minimum tillage). The displacement speed ideal for planting is one in which the groove is opened and closed without removing the over-ground, allowing the distribution of seed spacing and depth constant. The experiment was conducted in a soil classified as Typic Oxisol at Lageado Experimental Farm, Faculty of Agronomic Sciences, UNESP, Botucatu campus. This study aimed to evaluate the response of sorghum in four forward speeds (3, 5, 6 and 9 km h-1) and four systems of soil management: SD (direct seeding), GP (harrow + sowing), LPG (disc harrow and two light disking + sowing) and CR (scarification and seeding). Data was subjected to analysis of variance in a factorial 4 x 4 and a randomized block design with split plots. The following parameters were determined: average speed, average strength of the drawbar, the average power drawbar, theoretical field capacity of the tractor-equipment, fuel consumption per hour. For the conditions under which the experiment was conducted, it was concluded that the hourly fuel consumption was not influenced by tillage systems and was inversely proportional to the increase of speed work, and that the change of speed in the sowing operation did not provide additional the values of average traction force on the bar of the tractor-planter.

Influência do desgaste das garras dos pneus e das condições superficiais do solo nas operações de campo de um trator agrícola

The objective of this work was to compare the performance of a tractor equipped with used and new bias-ply tires (63.4% and 41.2%, front and rear tire waste, respectively), in three surface conditions: tillage soil, vegetal covered soil and firm soil. Field data were collected to calculate: forward speed, front and rear slippage tires, drawbar pull, available power at drawbar bar and fuel consumption. Results showed that both, tires and soil conditions, changed tractor capacity on developing drawbar traction. The worst performance was observed on tillage soil. The best performance of the tractor was observed at firm soil track. On the track with tilled soil, results showed that the forward speed was the lowest among the three soil conditions due to the front and rear slippage tires which was higher than vegetal covered and firm soil tracks. Fuel consumption results showed higher values on tilled tracks when compared with firm and vegetal covered tracks. The fuel consumption levels evaluated on bias-ply tires lead to significant changes on tractor’s performance at tilled soil, indicating that, at this condition, it’s necessary to replace the used tires by new tires. For vegetal covered soil operations, and also on firm soil conditions, used tires, at studied levels, indicated that these tires might still be used without tractor performance changing.

Características agronômicas e demanda energética de cultivares de soja sob efeito dos sistemas de preparo do solo

The aim of this study was to evaluate the influence of preparation: intermediate grade, minimum tillage and no-till on the agronomic characteristics and energy demand of transgenic soybean cultivars and non-GMO soybeans. Soil preparation aims at improving physical, chemical and biological conditions, aiming at good emergence and plant development. The different types of tillage may interfere with the agronomic characteristics and productivity of plants, and in energy use which can cause variation in production costs. Genetically modified plants can be one of the alternatives for reduction of production costs in crops by reducing pesticide applications, enabling higher productivity with less environmental impact. The test was conducted in 2010/2011 at the agricultural Experimental Farm Lageado, belonging to the Faculty of Agronomic Sciences – UNESP, located in the city of Botucatu, SP in an area using no-till systems for the past 12 years. The experiment was carried out in a 3 x 2 factorial, randomized treatments were comprised of three soil preparation systems, minimum cultivation, intermediate grade preparation and no-till, with two cultivars of soybeans: MGBR-46 Conquest (conventional), Valuable RR (Transgenic). The data obtained was submitted to variance analysis using Tukey test at a 5% probability. With the results analyzed it might be observed that there was no significant difference between treatments, in the variables, the percentage of soil cover, final soybean plant population, grain yield and plant height. The results obtained show that the no-till system resulted in higher productivity than conventional tillage and minimum cultivation. The higher specific energy use per area was observed in minimum cultivation with a chisel plough, when compared to the preparation across the grid. The greatest fuel consumption was to treat minimum cultivation with chisel plough. The highest values were found in the skating system of minimum cultivation, being greater in conventional tillage system. It is more satisfactory for the producer to sow transgenic soy using a no-till system, because productivity retrieved from that system compensates for fuel expenditure.

Demanda energética em diferentes manejos de solo e híbridos de milho

This study aimed to account the energy balance of six different farming systems: CMT (minimum tillage with transgenic corn); CMNT (minimum tillage with non-transgenic corn); PCT (conventional tillage with transgenic corn); PCNT (conventional tillage with non-transgenic corn); PDT (no-tillage system with transgenic corn) and PDNT (no-tillage system with non-transgenic corn). The study was carried out at the Experimental Farm Lageado FCA/Unesp, Botucatu - SP. The energy balance was performed by subtracting the total energy inputs by the total energy output. Energy efficiency was calculated by dividing the total energy output by the total energy inputs. The total values ​​of energy inputs and outputs were expressed in MJ.ha-1 (mega joules per hectare). To calculate the energy inputs were accounted the fuel consumption and lubricants, depreciation energy of machinery and implements, manpower and agricultural inputs. The energy outputs were calculated according to the maize yield. The result shows that the system PDT was the system that had better energy efficiency and the system that had the lowest efficiency was the PCT system. The system with lower energy demand was the PDT and the greatest demand was PCNT.

Desempenho efetivo e influência no sistema de limpeza da colheita mecanizada de cana-de-açúcar utilizando diferentes velocidades de deslocamento e rotações do extrator primário

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Utilização de trocadores de calor de placas em espiral em processos da indústria siderúrgica

Stricter environmental policies are shown necessary to ensure an effective pollutant emission control. It is expected for the present year of 2015, that Brazil will assume, at the 21th United Nation's Climate Change Conference (COP21), implementation of commitment to a low carbon economy. This positioning affects the industrial environment, so that is deemed necessary to search for new technologies, less aggressive to the environment, so the adequacies to the new emission policies do not cause a negative effect on production. Almost all of the processes performed in the steel industry demand burning fuel and, therefore, flue gases are sent to the atmosphere. In this present work is discussed the utilization of heat exchangers so, by recovering part of the available heat from the flue gases of certain industrial process, the combustion air is preheated. The combustion air preheat results in less energy requirement, i.e., less need of fuel consumption and, in addition, minor amount of pollutants to be emitted. Due to better fitting to the process, it is studied the utilization of spiral plate heat exchangers. The heat exchanger dimensioning is made by an iterative method implemented in the software Microsoft Excel. Subsequently are analyzed the gains in terms of process's thermal efficiency improvement and the percentage of fuel saving. The latter implies in reduction of the same percentage of greenhouse gases emission