CIESC Journal ›› 2020, Vol. 71 ›› Issue (7): 3018-3030.DOI: 10.11949/0438-1157.20200062

• Fluid dynamics and transport phenomena • Previous Articles     Next Articles

EMMS-based flow regime study of circulating fluidized beds

Kaicheng CHEN1,2(),Yujie TIAN1(),Fei LI1,3(),Hao WU4,Wei WANG1,2   

  1. 1.State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
    2.Sino-Danish College, University of Chinese Academy of Sciences, Beijing 100049, China
    3.Innovation Academy for Green Manufacture, Chinese Academy of Sciences, Beijing 100190, China
    4.Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800 KongensLyngby, Denmark
  • Received:2020-01-15 Revised:2020-03-12 Online:2020-07-05 Published:2020-07-05
  • Contact: Fei LI

基于EMMS的循环流化床流域研究

陈恺成1,2(),田于杰1(),李飞1,3(),吴昊4,王维1,2   

  1. 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.中国科学院大学中丹学院,北京 100049
    3.中国科学院绿色过程制造创新研究院,北京 100190
    4.Department of Chemical and Biochemical Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
  • 通讯作者: 李飞
  • 作者简介:陈恺成(1995—),男,硕士研究生,kcchen@ipe.ac.cn|田于杰(1991—),男,博士,助理研究员,tianyj@ipe.ac.cn
  • 基金资助:
    国家自然科学基金项目(21625605);国家重点研发计划项目(2017YFB0602700);中国科学院绿色过程制造创新研究院(IAGM-2019-A13)

Abstract:

The design, enlargement, and optimization of fluidized beds require a basic understanding of the watershed. However, the division of watersheds for gas-solid systems still has many controversies. In this paper, the state-of-the-art regime studies are summarized with the main disputes highlighted. Inconsistency is found on the demarcation of the fast fluidization. The steady-state EMMS (energy minimization multi-scale) drag model is thus integrated into two-fluid model (TFM) to simulate a circulating fluidized bed (CFB) with a variety of gas velocities and solids holdups. Particle refluxing and slugging are found in the simulation results, whereby bound the fast fluidization regime. A regime diagram is drawn, where the main features of the different regimes in CFBs are presented.

Key words: circulating fluidized bed, regime transition, mesoscale, computational fluid dynamics, EMMS

摘要:

流化床的设计、放大和优化需要对流域有基础的认识,然而气固系统的流域划分至今仍存在诸多争议。总结了气固流化系统流域划分的研究现状,并分析了流域划分的主要争议,发现文献中对快速床的界定存在分歧。通过耦合基于稳态EMMS的曳力模型开展双流体模拟,对不同气速和颗粒浓度下的循环流化床进行了数值研究。模拟结果捕捉到了颗粒回流、节涌等现象,据此确定了快速床的操作边界并绘制了流域图,该流域图能够展示循环床中的各流域形态。

关键词: 循环流化床, 流域转变, 介尺度, 计算流体力学, EMMS

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