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Öğe Comparing of ridge planting performance of precision planters equipped with shoe and disc coulters [Baltalı ve Diskli Gömücü Ayağa Sahip Tek Dane Ekim Makinalarının Sırta Ekim Performanslarının Karşılaştırılması](Ankara University, 2017) Yazgi A.; Yalçin H.; Aykas E.; Tozan M.The objective of this study was to determine ridge planting performance of the precision seeders equipped with shoe and disc type coulters and to reveal differences between seeders. To meet this target both laboratory and field experiments were conducted. Seed spacing distribution uniformity of the machines were determined using sticky belt tests at the laboratory. The values of plant spacing distribution uniformity, ratio of plant emergence, seeding depth uniformity, negative driven wheel slips of the seeders and driven wheel slips of the tractors were determined by the tests carried out on field conditions. Based on the experimental results, it was determined that, all seeders performances in terms of seed spacing distribution uniformity were found in “good” quality under laboratory conditions, while seeding quality in ridge planting on the field was determined lower than laboratory conditions for all seeders. But seeders equipped with disc type coulters were determined more effective than seeders equipped with shoe type coulters in high quality corn seeding under field conditions. It was found that seeders equipped with disc type coulters provided both higher plant emergences and more uniform seed depths in firm terms. The values of negative driven wheel slips of the seeders were determined as 0.93-5.34% and 9.14-10.24% for shoe type and disc type seeders, respectively. The values of driven wheel slips of the tractors were ranged from 1.38% to 3.83% and from 5.39% to 9.50% for shoe type and disc type seeders, respectively. Based on the all findings it was determined that seeders equipped with disc type coulters should be used in ridge planting. © Ankara Üniversitesi Ziraat Fakültesi.Öğe An evaluation of seed spacing accuracy of a vacuum type precision metering unit based on theoretical considerations and experiments [Teorik ve deneysel verilere dayali{dotless} olarak vakumlu tek dane ekim ünitesinin tohum arali{dotless}gi{dotless} düzgünlügünün degerlendirilmesi](Turkiye Klinikleri Journal of Medical Sciences, 2012) Önal I.; Degirmencioglu A.; Yazgi A.Currently the most widely used machine for precision seeding of cotton and maize seed is vacuum type. The capture of seeds by vacuum plate and the release of seeds from the vacuum plate should be performed precisely without missing or doubling. The physical phenomena should be clarified theoretically to understand how the precision seeding mechanism works. To solve these problems, an attempt was made to develop a nomogram using equations describing the technical characteristics of the seeder used in this study and to describe the seed capture mechanism relying on basic principles of fluid mechanics and aerodynamic properties of seeds. Seed spacing accuracy tests were performed to test the theory on a sticky belt in the laboratory. Quality of feed index, miss and multiple indices, and precision have been taken as a set of criteria for seed spacing accuracy. The regression models developed using the data obtained via sticky band tests showed that 16 seeds s-1 was the upper limit of seed release frequency (SRF) for cotton and maize seeds. The upper limit of vacuum plate peripheral speed was found to be 0.34 m s-1. The use of 72 holes instead of 26 holes in the vacuum plate at 6.3 kPa created a vacuum band in the width of 10 mm around holes and this increased the multiple index and caused a reduction in seeding performance. For this reason, the use of vacuum plates with 60 or 52 holes is recommended for cotton seed. The forward speed of either 1.0 or 1.5 m s-1 was found to be acceptable for the seed spacing of 0.05 and 0.10 m, respectively. Aerodynamic calculations verified that widely used vacuum plates with 26 holes were the appropriate ones for seeding maize seeds. The performance indices, namely the quality of feed, and miss and multiple indices, reduced significantly for cotton and maize seeding when the precision metering unit was run at 20% (11°) slope to the right as compared to the no slope condition. © TÜBİTAK.Öğe Optimization of the seed spacing uniformity performance of a precision seeder using spherical materials and response surface methodology(American Society of Agricultural and Biological Engineers, 2010) Yazgi A.; Degirmencioglu A.; Onal I.; Bayram E.The objective of this study was to optimize the seed spacing uniformity performance of a precision seeder using spherical materials and Response Surface Methodology (RSM) and to verify the optimum levels of the variables. The variables considered in the study included vacuum on seed plate, the diameter of seed holes and peripheral speed of the seed plate. Spherical materials made of plastic were used and experiments based on Central Composite Design (CCD), one of the designs in RSM were carried out in the laboratory. The data obtained were divided into three different groups in order to obtain the values of Multiple Index, Quality of Feed Index, Miss Index. Other performance indicators called root mean square deviation and CP3 were also calculated and evaluated in the study. Prediction functions mostly for quality of feed index in polynomial form allowed the calculation of the optimum level of each independent variable. Optimum levels of the variables obtained for each spherical material were tested and verified.Öğe Performance modeling and seed releasing characteristics of a corn planter metering unit using response surface methodology(American Society of Agricultural and Biological Engineers, 2017) Yazgi A.; Taylor R.K.; Navid H.; Weckler P.The objective of this study was to develop prediction performance functions and determine the seed releasing characteristics of seed meter disks based on metering rate and pitch angle at different levels using Response Surface Methodology (RSM). An AGCO White 9000 planter row unit was tested using two seed shapes and associated disks in controlled laboratory conditions. Experiments were designed based on the two-variable Central Composite Design (CCD), one of the RSM designs. Effects of metering rate and row unit pitch (seed tube tilt angle) in their five levels were investigated, on performance and seed release characteristics. A video recording system allowed simultaneous recording of rear and side views of seed exiting the seed tube on the row unit. A MATLAB program in combination with image processing algorithms was used to analyze video. The performance indicators investigated were quality of feed index (QFI), and multiple and miss indices. Seed release characteristics of interest were side and rear angles and time between seeds. Based on the experimental results, QFI values were found 99.0% (maximum) and 100% (maximum) for using flat and round corn seed disks, respectively. The maximum side angle ranged from 33.5° to 48.3° for the flat seed disk and 33.4° to 47.6° for the round seed disk. The maximum rear angle ranged from 5.1° to 15.1° for the flat seed disk and 6.4° to 17.6° for the round seed disk. In addition to experimental results, model equations were also developed to predict QFI, side and rear angles as functions of metering rate and pitch angle. Quality of feed index functions were maximized and the optimum values of metering rate and pitch angle values were found to be 800 seeds min-1 and -2.6° for the flat meter disks. The optimum values for the round meter disks were a metering rate of 409.4 seeds min-1 and a pitch angle of 0°. © 2017 American Society of Agricultural and Biological Engineers.Öğe Seed mixture flowing characteristics of a seed drill for mixed seeding(American Society of Agricultural and Biological Engineers, 2017) Yazgi A.; Aykas E.; Dumanoglu Z.; Topcu G.D.Mixed seeding is a new approach for forage plant production in Turkey. However, there has been little research into simultaneously seeding multiple crops. The objective of this study was to evaluate the applicability of a seed drill for mixed seeding. Machine performance was determined using pure barley (Hordeum vulgare L.), pure common vetch (Vicia sativa L.), and mixtures of both seeds at different seed mixture ratios. The indicators of seeding quality, flow uniformity, and seed distribution uniformity across the rows were determined by measurement of seed weights. The other indicator, in-row seed spacing uniformity, was determined by sticky belt tests in controlled laboratory conditions using a computer-aided measurement system. Five different mixture rates of barley:vetch (100:0, 75:25, 50:50, 25:75, and 0:100) and three forward speed values (1.0, 1.5, and 2.0 m s-1) were used in the experiments. While flow evenness and seed distribution uniformity across the rows unit were controlled by the coefficient of variation (CV), in-row seed spacing uniformity was tested based on the variation factor (Vf) and goodness criterion (?). Based on the experimental results and calculations, it was found that the domestic type combined seed drill could be used effectively for seeding of barley and vetch mixtures at different seed mixture ratios. While the CV values of flow evenness and seed distribution uniformity of each row unit were found to range from 0.8% to 3.7% and from 1.1% to 8.9%, respectively, goodness criterion values ranged from 47.2% to 78.4%. These statistical data give valuable information about the machine performance and the possibility of efficiently using combined seed drills for mixed seeding. © 2017 American Society of Agricultural and Biological Engineers.
