(2.中国科学院大学化学化工学院, 北京 100049)
【摘要】采用离散单元法 (discrete element method, DEM) 模拟了工业尺度螺旋输送器中两种不同密度与粒径的颗粒的流动状态与混合过程。采用Lacey混合指标的定量分析表明, 该输送器的混合性能强烈地依赖于操作条件和结构尺寸, 转速和物料的添加速率对混合效果影响最大, 其次是混合段螺距和物料粒径。根据工业生产的具体要求, 可参考上述发现合理地选择技术参数、提高混合效率、降低能耗。
【基金资助】 中国科学院战略性先导科技专项 (XDA07080000) ; 中国科学院前沿科学重点研究项目 (QYZDJ-SSW-JSC029) ; 中国科学院科技创新交叉与合作团队; 国家自然科学基金项目 (91434201) ;
Simulation on mixing granular materials in screw conveyor
(2.School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing, China 100049)
【Abstract】Flowing and mixing granular materials of two different sizes and densities in an industrial-scale screw conveyor were studied by computer simulation using the discrete element method (DEM). The quantitative analysis results by the Lacey M showed that the mixing performance of the screw conveyor was dependent strongly on operational conditions and structural dimensions. Both screw rotating speed and material feeding rate had dominant effects on mixing efficiency, followed by granular material sizes and screw pitch in the mixing region. To reduce energy consumption and improve mixing performance in production, reasonable operation parameters of screw conveyors could be selected according to these findings.
【Keywords】 granular material; discrete element method; screw conveyor; mixing mechanism; large-scale simulation;
【Funds】 “Strategic Priority Research Program” of the Chinese Academy of Sciences (XDA07080000) ; Key Research Program of Frontier Science, CAS (QYZDJ-SSW-JSC029) ; CAS Interdisciplinary Innovation Team; National Natural Science Foundation of China (91434201) ;
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