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螺旋输送器中颗粒混合过程的模拟

戚华彪1 徐骥1 宋文立1 葛蔚1,2

(1.中国科学院过程工程研究所多相复杂系统国家重点实验室, 北京 100190)
(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。

【关键词】 颗粒;离散单元法;螺旋输送器;混合机理;大规模模拟;

【DOI】

【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

QI Huabiao1 XU Ji1 SONG Wenli1 GE Wei1,2

(1.State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China 100190)
(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;

【DOI】

【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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This Article

ISSN:0438-1157

CN: 11-1946/TQ

Vol 69, No. 01, Pages 371-380

January 2018

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Article Outline

Abstract

  • Introduction
  • 1 Simulation method
  • 2 Simulation conditions
  • 3 Measurement method
  • 4 Result analysis
  • 5 Conclusions
  • Symbol description
  • References