Effect of feeding rate on flow field inside classifier

doi:10.11949/j.issn.0438-1157.20150332

Abstract

Abstract:

The flow field in FTW turbine classifier is studied by using simulation of the dynamic pressure, the turbulent kinetic energy, velocities using computational fluid dynamics software Fluent. Effects of feeding rate on the inner flow field were compared and analyzed. The results showed that when the feeding rate increases, the dynamic pressure is reduced while its distribution is symmetrical. The turbulent kinetic energy is reduced with more uniform distribution and increased radial velocity, decreased tangential velocity and decreased axial velocity. The greater impact on the flow field is the larger axial velocity favorable for stable classifying. Experimental measurement of particle size distribution verified some of the above results.

Key words: turbine classifier, feeding rate, flow field analysis, optimization, numerical simulation

摘要：

用Fluent软件模拟仿真分析了FTW型涡轮空气分级机内部流场的动态压力、湍动能、流动速度的分布, 对比分析不同加料速度对分级机内部流场的影响。结果表明:加料速度增加, 动态压力降低, 但分布曲线的对称性更好;湍动能降低, 但分布更为均匀;径向速度增加, 切向速度和轴向速度都降低, 且分布更为均匀, 其中轴向速度较大, 对流场影响更大;有利于流场稳定, 更有利于物料分级。实验测试了分级粒径分布部分支持这些效果。

关键词: 涡轮空气分级机, 加料速度, 流场分析, 优化, 数值模拟

CLC Number:

TQ174.6

DANG Dong, WANG Kejian. Effect of feeding rate on flow field inside classifier[J]. CIESC Journal, 2015, 66(S1): 159-164.

党栋, 王克俭. 加料速度对分级机内部流场的影响[J]. 化工学报, 2015, 66(S1): 159-164.

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