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| Application of CFD technology in air-assisted spraying in orchard and analysis of its prospects |
| Zhou Liangfu1, Xue Xinyu1, Jia Weidong2, Ding Suming1, Sun Zhu1 |
| 1.Nanjing Research Institute for Agricultural Mechanization, Ministry of Agriculture, Nanjing, Jiangsu 210014, China; 2.Institute of Agricultural Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China |
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Abstract With the rapid development of numerical computational theory and computer technology, CFD technology has been extensively used in agricultural engineering to vividly visualize flows. This review mainly focused on applications of CFD technology in structure optimization(number of blades, backflow structure, stress in blade, blade angle and duct configuration)and performance prediction(efficiency and noise)of fans in air-assisted sprayer as well as validation of standard k-ε turbulence model. Additionally, the feasibility of Lagrangian method for handling interaction between air and disperse phase is verified by applying CFD technology to identify microscopic characteristics of spray. Unfortunately, CFD technology cannot provide any information about atomization mechanism of spray pre-sently. The standard k-ε turbulence model has been applied and verified in internal flow and droplet deposition on canopy. However, the effects of canopy on turbulent kinetic energy dissipation are not explored in detail, and there is lack of study on droplet deposition model. Finally, a few prospects for structure optimization and performance prediction of fans, atomization mechanism and effects of canopy on spraying flow are highlighted. Furthermore, it is proposed that how to determine the spray capacity and velocity which can match a specific canopy should be the hotpot problem in future.
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Received: 22 January 2014
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