摘要
以数值模拟对偏心搅拌时的固液悬浮特性进行了研究,物料选用固相体积分数为15%、粒径为135μm的球形玻璃珠-水两相体系,采用标准k-ε湍流模型模拟液相流动,采用欧拉多相流模型模拟悬浮过程,分析了偏心率对搅拌流型、颗粒浓度分布及能量消耗的影响.结果表明,偏心搅拌时浓度分布比中心搅拌更为均匀,可改善固液悬浮效果,且具有节能功效;不同偏心率的改善效果不同,偏心率e=0.21时悬浮效果最理想,此时的临界悬浮转速约为中心搅拌时的80%,消耗的功率约为中心搅拌时的90%.
Solid-liquid suspension performance in an eccentrically stirred tank was numerically investigated by using Fluent software. The two-phase system studied consisted of globose glass beads and water. Solid particle volume fraction was 15%, and the particle diameter 135 μm. Standard k-ε turbulent model was used to simulate the steady liquid phase flow field, and the unsteady solid-liquid suspension process was simulated with the Eulerian multiphase model. The flow pattern, solids particles concentration distribution and power consumption were extensively analyzed. The results show that, compared with the concentric agitation, the eccentric agitation led to a more homogeneous particle concentration distribution, improved the suspension performance and saved energy. Besides, the improvement of solid-liquid suspension performance varied with the eccentricity. In this work, solid particles reached the best suspension when the eccentricity, e, was 0.21. The critical suspension velocity and power consumption were about 80% and 90% of those in the concentric agitation respectively.
出处
《过程工程学报》
EI
CAS
CSCD
北大核心
2008年第6期1064-1069,共6页
The Chinese Journal of Process Engineering
关键词
四折叶桨
搅拌槽
偏心搅拌
固液悬浮
four-pitched-blade turbine
stirred tank
eccentric agitation
solid-liquid suspension
