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| dc.contributor.author | Achenef, Tarekegn Mekonen | |
| dc.date.accessioned | 2022-03-28T07:05:29Z | |
| dc.date.available | 2022-03-28T07:05:29Z | |
| dc.date.issued | 2021-10 | |
| dc.identifier.uri | http://ir.bdu.edu.et/handle/123456789/13337 | |
| dc.description.abstract | Agricultural mechanization provides a significant input to agriculture for performing seasonal farming operation during pre-sowing of seeds, plant protection chemicals using sprayers and post-harvesting of crops with harvesting machineries. In Ethiopia, Teff is principally produced by smallholder farmers in a traditional way such as broadcasting of seeds, and it is a very laborious process. Teff row seeding technique is a promising method to boost total production. In this paper, Teff row seeding system was designed and modeled. The system principally consists of a seed-metering mechanism, an air supply tube for seeds, distributor, blower, and other components were chosen and designed based on taking human ergonomics into consideration. The effect of working parameters that can affect the Teff seeding process are the Teff agronomy, wind speed, moisture content, Teff dropping height, Teff particle weight or driving velocity and these were optimized to enhance system performance. The modeling and optimization of the behavior of these parameters are addressed by using analytical, and numerically approaches. To design the Teff seeding machine and to model the effects of the wet -flow behavior of Teff, a pneumatically operated row seeding system was considered. ANSYS-CFD was utilized to predict the flow pattern of Teff seed particle both in pipes and in discretized domain. It showed that, it has a good agreement with the previous studies. The liquid bridge model was used to predict the flowability of Teff seed, a nd the results suggest that a micro liquid content of up to 4*10-6 times the particle volume has no discernible effect on seed flowability. However, the seeds may agglomerate together if exposed to a wet environment with more than 80% relative humidity for an extended period of time. The Box Behnken design method in design expert13 software was adopted to determine the optimal working parameters and the optimum results were a particle velocity of 5m/s, seed droplet height of 30cm, a seed layer thickness of 3cm, an impact velocity of 16m/s and a seed trajectory angles of 6°. To conclude that, a pneumatic operated Teff row seeding system was modeled and designed by considering the effect of working parameter and these can meet the standards and the agronomy requirements. This research can be used for a small amount of seeds in wet weather conditions and a hilly mountain area. Keywords: Wet-flow behavior; Teff seed; Angle of trajectory, Seed layer thickness; Relative Humidity Solid work; ANSYS-CFD; RSM; LBM. | en_US |
| dc.language.iso | en_US | en_US |
| dc.subject | Mechanical Design | en_US |
| dc.title | Pneumatic Operated Teff Row-Seeding Machine Design and Optimization of the Wet-Flow parameter of Teff | en_US |
| dc.type | Thesis | en_US |
