浙江农业学报

• 生物系统工程 • 上一篇    下一篇

结合Fluent仿真软件的循环式干燥机改进设计研究

  

  1. (1 新疆农业大学 机械交通学院,新疆 乌鲁木齐 830052;2 新疆农业工程装备创新设计重点实验室,新疆 乌鲁木齐 830052)
  • 出版日期:2015-04-25 发布日期:2015-04-30

Improved design of circulating dryer based on Fluent

  1. (1 Mechanical and Traffic College, Xinjiang Agricultural University, Urumqi 830052, China;2 Key Laboratory of Agricultural Engineering Equipment Innovation Design of Xinjiang, Urumqi 830052, China)
  • Online:2015-04-25 Published:2015-04-30

摘要: 干燥室内热介质的分布均匀性直接影响物料的干燥效果。应用Fluent软件进行循环式干燥机的数值模拟,采用标准k-ε湍流模型,用多孔介质模型代替物料层,得到热介质在干燥室内的流动特征,对干燥室进行改进优化设计。结果表明,气流进入原模型的干燥室后撞击壁面形成的涡流区,导致物料层风速的均匀性较差;改进后干燥室内的涡流区可明显减小,整个流场的均匀性得到改善。气流穿过各物料层的速度不均匀系数分别从19.13%,6.94%和8.01%降至7.90%,3.15%和5.68%。

关键词: 干燥机, 流场, 数值模拟, 优化

Abstract: The uniform distribution of heat medium in drying chamber affects the drying effect of materials. A simplified model of circulating dryer was established, and was used to simulate the flow field in a drying chamber based on Fluent. It consisted of the standard k\|ε approach to model the flow turbulence, and used porous medium model instead of material. The velocity distributions in chamber flow field were obtained and used to analyze the improved designs based on the original structure. The results showed that four vortex zones were formed in original structure because of hitting toward the wall, which led to uneven velocity of material. The ladder\|shaped arrangement of baffle at the entrance could reduce eddy current of flow field, and the uniformity of whole flow field were improved. Uneven coefficient of air velocity through the material decreased from 19.13%, 6.94% and 801% to 7.9%, 3.15% and 5.68%, respectively.

Key words: dryer, flow field, numerical simulation, optimization