Determinação das propriedades geométricas, físicas e mecânicas do sistema fruto-pedúnculo-ramo do cafeeiro

O método de elementos finitos tem sido empregado no projeto de máquinas e para o estudo do comportamento dinâmico do cafeeiro. Objetivou-se, neste trabalho, determinar as propriedades geométricas, físicas e mecânicas do sistema fruto-pedúnculo-ramo do cafeeiro. As dimensões foram determinadas por meio de processamento de imagens, as massas e os volumes mensurados utilizando-se balança e proveta, respectivamente. Os módulos de elasticidade foram determinados por meio de ensaios mecânicos de compressão, tração e flexão, para os frutos, pedúnculos e ramos, respectivamente. Os coeficientes de Poisson foram determinados a partir das deformações longitudinais e transversais dos frutos e pedúnculos. A razão de amortecimento foi determinada por meio das curvas de decaimento utilizando-se o método de decremento logaritmo. Concluiu-se que as dimensões e a massa dos frutos apresentaram tendência de aumento na medida em que seu estádio de maturação evoluiu. Os módulos de elasticidade dos frutos e dos pedúnculos no estádio de maturação verde foram superiores aos valores para o estádio de maturação cereja

Olive removal with pneumatic branch shaker and abscission chemical

This study involves designing a branch shaker operating with an air compressor and its application for harvesting olives. Fruit detachment force (FDF) and fruit weight (W) were measured and hence the changes in the percentage of removed fruits with shaking were determined at different maturity times. During the harvesting season, two sets of experiments were conducted to test the shaker in the removal of Halhali cultivar olives (Olea europaea L.) with and without application of abscission chemical (ethrel). Experiments were also carried out to determine the effect of the chemical on fruit detachment force, fruit weight, and mechanical harvesting efficiency. Shaking tests showed that the removal percentage of olives without chemical application was lower than 50%. However, application of abscission chemical reduced the FDF/W ratio and thus increased the removal percentage of olives. The lowest fruit detachment force and the highest fruit removal (96%) were obtained by employing a frequency of 24 Hz and 12.5 mL/L concentration of abscission chemical with constant amplitude of 60 mm. Moreover, it was found that the fruit removal efficiency increases with decreasing olive detachment forces. © 2005 Elsevier Ltd. All rights reserved

Conservation and conventional tillage methods on selected soil physical properties and corn (Zea Mays L.) yield and quality under croppin system in Turkey

This study was conducted to determine the effects of conventional and conservation tillage on the some soil physical properties, penetration resistance (PR), seedling emergence rate, yield and yield components under southestern of Turkey conditions. The experiments were carried out at 2003 and 2004 years in a clay loam soil. Six different soil tillage methods in corn production were tested. The experiment was performed in randomized block design with six treatments and each treatment consists of three replications. No significant (p>0.05) treatment differences in seedling emergence were found between the tillage treatments for both years. Plant height was found significant between years while treatment effects were not significant. However, the highest plant height was obtained in 2004 under CT tillage method. The stalk thickness was found significant between years while treatment effects were not significant. The cob length was not found significant between years and treatments.The lowest cob length was obtained under NT method. It was found that yield was significantly (p<0.01) different between years. The yield in the second year was found to be higher than that of the first year. The highest yield was found in CT method as 678.00 kg/da and the lowest yield was found in RT4 method as 535.66 kg/ha in year 2003. The highest yield was found in CT method as 778.66 kg/da and the lowest yield was found in RT4 method as 642.33 kg/ha in year 2004. The highest fuel comsumption was obsorved as 33.48 Lha-1 in conventional method (CT) whereas the lowest value was found in direct seeding method as 6.6 Lha-1

Short-term effects of tillage and residue management following cotton on grain yield and quality of wheat

Grain yield and quality of winter wheat (Triticum durum L) are affected by several factors, and crop management has a very important role among them. A 3-year (from 2003-04 to 2005-06) field experiment under irrigation was carried out at Diyabakir in the South East Anatolia Region of Turkey to evaluate immediate effects of tillage and residue management systems after cotton (Gossypium hirsutum L.) on grain yield and quality [thousand grain weight (TGW), test weight (TW), protein content (PC) and mini sedimentation (mini SDS)] of durum wheat, and correlations among these parameters. A split plot design with three replications was used, in which two residue management treatments [collecting and removing cotton stalks from plots (S-Rem), and chopping and leaving of cotton stalks in plots (S-Lev)] were main plots, and six tillage and/or wheat planting method combination treatments [moldboard plough + cultivator + broadcast seeding + cultivator as conventional tillage-I (CT-I), moldboard plough + cultivator + drill as conventional tillage-II (CT-II), chisel plough + cultivator + drill as vertical tillage (VT), two passes of disk harrow + drill as reduced tillage-I (RT-I), rotary tiller + drill as reduced tillage-II (RT-II), and no-till ridge planting (RP)] were sub-plots. The effect of cotton residue management on grain yield, TW, PC, mini SDS was not significant, but S-Rem (51.21 g) gave significantly higher TGW than S-Lev (50.63 g). Tillage and/or wheat planting method combination treatments had a significant effect on grain yield. TGW and TW, but did not significantly influence PC and mini SDS. Conventional tillage with broadcast seeding (CT-I) treatment produced the lowest wheat grain yield (5.395 Mg ha(-1)), while there were no significant differences in grain yield among the other five tillage treatments (yields ranged from 5.671 to 5.819 Mg ha(-1)). In spite of supplemental irrigations, the variability of weather conditions, particularly the amount and distribution of rainfall during the growing season, had a significant influence on wheat grain yield and quality parameters (TGW, TW, PC, mini SDS). Grain yield had a significant positive correlation with TGW, but it did not show any relationship with other grain quality parameters. In conclusion, the findings suggest that conventional tillage with broadcast seeding would be less effective in producing grain yield of wheat compared to other five tillage treatments with row planting, while management of the previous cotton stalks may not have any effect on yield and quality of wheat except TGW. (C) 2010 Elsevier B.V. All rights reserved

Soybean threshing efficiency and power consumption for different concave materials

Soybean is one of the most slowly established crops in many developing countries. During recent years, greater interest has been given to the cultivation and mechanization of soybean. Particularly, soybean threshing is an important problem because of the product loss. Most of the trials for soybean threshing have been on the structure of beaters, although the type and structure of contrbeaters are as important as structure of beaters. This work designed and tested concaves made of different materials with respect to threshing efficiency, power requirement and specific power consumption at various feed rates and drum peripheral speeds. Regression equations have been established. The multiple regression technique was used to study the relationship among different variables, namely, concave type, feed rate and drum peripheral speed in relation to three dependent variables, namely, threshing efficiency, power requirement and specific power consumption. An experimental model of a soybean thresher without a cleaning and separating unit was developed. The threshing machine had a peg-tooth drum and was powered by a 4 kW electricity motor. Also, four concaves made of different materials were used for the trials. SA-88 soybean variety was used for the trials. The four concave types were PVC, rubber, chromium, and steel plate with three feed rates (360 kg/h, 720 kg/h, and 1,080 kg/h) and five beater peripheral speeds (7.95 m/s, 9.10 m/s, 10.54 m/s, 12.16 m/s, 14.66 m/s). Speed and feed rate were found to a have a significant effect (p < 0.01) on power requirement. The power requirement increased with increasing feed rate and drum peripheral speed. The specific power consumption decreased with increasing feed rate. Threshing efficiency decreased with increasing feed rate and increased drum peripheral velocity significantly improved the threshing efficiency. The highest threshing efficiency was achieved with the chromium type of contrbeater, followed by PVC, the sheet iron, and the rubber

Tillage effects on sunflower (helianthus annuus, l.) emergence, yield, quality, and fuel consumption in double cropping system

The relation between crop growing and soil tillage treatment are play important role in agricultural production. Soils under conventional tillage (CT) generally have lower bulk density and associated higher total porosity within the plough layer than under no tillage (NT). No-till farming can reduce soil erosion, conserve soil moisture and minimize labor and fuel consumption. The aim of this study were to investigate the effects of conventional, reduced and notillage methods on soil physical properties, sunflower yield and yield components, protein and oil content and fuel consumption in Southeastern of Turkey. Six tillage methods for the second crop sunflower were tested and compared each other within after lentil harvesting at 2003 and 2004 years in a clay loam soil. According to results, the first year, the bulk density had decreased from 1.29 to 1.09 g cm-3, the second year the ?b had decreased from 1.41 to 1.23 g cm-3. Differences between years and tillage methods in terms of yield were found signifi cant (p&lt;0.05). However, no differences were found between the NT and CT. There were also no signifi cance differences in content of protein, oil and ash among six tillage methods. The highest fuel consumption was measured in conventional method (CT) whereas the lowest value was found in direct seeding method as 33.48 L ha-1 and 6.6 L ha-1, respectively

THE CHANGE OF SHEAR FORCE AND ENERGY OF COTTON STALK DEPEND ON KNIFE TYPE AND SHEAR ANGLE

The shear force and energy values of biological materials are very important data for suitable design of a cutting and pruning machines and related equipment. The objective of this study was to determine shearing force and shearing energy of cotton (Gossypium hirsutum L.) stalk at different shoots diameter as a function of knife type and knife edge angle. Dependent variables were maximum cutting force and cutting energy. The samples were obtained from the cotton experimental field at vegetation season for each plot. A universal test machine was used to measure the cutting force and the energy. The cutting energy was calculated by measuring the surface area under the cutting force-deformation curve. As a result, the main effect of the knife edge angle on the cutting force and energy were found significant. The best and minimal results were determined at serrated 2 knife types to be 69.61 N and 25.61 Ncm, respectively, followed by the serrated 1 and flat knife. The highest values were observed at flat knife type. Nevertheless, the cutting force and cutting energy increased with an increase in the knife edge angle from 50 degrees to 90 degrees. The maximum values were obtained at 90 degrees both cutting force and cutting energy. At this angle, while the maximum cutting force and cutting energy were determined to be 93.18 N and 31.60 Ncm, respectively. The main minimum values were obtained at 50 degrees angle. Cutting force and energy values of cotton stalk were found highly correlated with the stalk diameter. Cutting force and energy increased with increase diameter of stalk. The maximum cutting force and cutting energy were obtained at 29.20 mm(2) cross-sectional area as 102.30 N and 41.97 Ncm, respectively, while the minimum values of cutting force and cutting energy were obtained at 13.84 mm(2) cross-sectional area as 47.28 N and 16.76 Ncm, respectively.Scientific Research Fund of Dicle University [DUBAP-08-ZF-59]; Dicle UniversityThis study was carried out with the test machine that the buy a project supported by the Scientific Research Funding (DUBAP-08-ZF-59) of Dicle University. The authors would like to thank Dicle University for providing the Material Test Machine and financial support

Cutting parameters of some grape varieties subject to the diameter and age of canes

Grape is an important product for the economy of Turkey and it will continue to play an important role in worldwide grape production due to its large number of varieties, favorable ecological conditions and large production areas. However, pruning and harvesting of grape berries are performed manually with a labor intensive procedure. Therefore, production cost is very high and labor efficiency is low in vineyards. However, pruning and harvesting are the most critical operations in vineyard management. Information regarding the cutting of canes of different grape varieties is very important for a proper harvest machine design as well as the efficient use of energy. In this study, cutting force and cutting energy were measured by considering the factors of grape canes diameter and age of canes. One and two year old grape canes from the Genc Mehmet, Bogazkere and Okuzgozu local varieties were used as experimental material. The canes were obtained from a commercial vineyard in the Diyarbakır province located in southeastern Turkey. Lloyd, LRX plus series, materials testing machine was used for cutting tests. Statistically significant differences were determined between the cutting properties of grape varieties. The cutting force and cutting energy increased with increasing diameter and age of canes. © 2019 Parlar Scientific Publications. All rights reserved