摘要
针对复合移动床反应器内固体颗粒运动,采用离散单元法模型(DEM)考察布料器分别为扇形开口和矩形开口时,布料器转速和开口对颗粒运动的影响,并基于文献结果论证了本文模型的准确性。模拟结果表明:1对于不同布料器,颗粒在移动床中呈现平推流和汇聚流两种流动形态。2随布料器转速及开口的增加,颗粒质量通量非线性增加。3随布料器转速的增加,下落床径向上颗粒分布更均匀;随布料器开口的增大,下落床径向上颗粒分布范围变大,颗粒分布更均匀;对下落床径向上颗粒分布,布料器扇形开口时分布呈U形、矩形开口时分布呈M形。4沿反应器轴向向下,颗粒分布有均匀化趋势;扇形开口布料器对颗粒分布的离散系数大于1,矩形开口布料器对颗粒分布的离散系数约为0.5。
In this paper,the particle flow in a combined-moving bed reactor was simulated using the discrete element method(DEM),and the accuracy of DEM simulation was verified by a comparison with the literature results. The effects of rotational speed and open-hole size of two kinds of distributing devices were analyzed. The results showed that:①There are two kinds of flow patterns for the two distributing devices,i.e.,plug flow and funnel flow;②particle mass fluxes increased non-linearly with the increase of rotational speed and open-hole size of the distributing devices;③along the radial direction,particles were distributed more uniformly with increasing the rotational speed and open-hole size,and the distribution showed U and M shapes for the two kinds of distributing devices;④the radial distribution of particles were more uniformly downwardly along the axial direction,with values of the variance coefficient exceeding 1.0 for the fan-shaped hole distributing plate,and 0.5 for another distributing plate.
出处
《化工进展》
EI
CAS
CSCD
北大核心
2014年第10期2576-2582,共7页
Chemical Industry and Engineering Progress
基金
国家973计划项目(2011CB201306)
关键词
离散单元法
数值模拟
颗粒流
移动床
布料器
discrete element method
numerical simulation
granular flow
moving bed
distributing device