Article
Engineering, Chemical
Shijiao Li, Peng Zhao, Ji Xu, Li Zhang, Junwu Wang
Summary: This study investigates the fluidization of polydisperse particles in bubbling micro-fluidized beds using CFD-DEM. The study validates the method by comparing it with experimental measurements and then performs a detailed analysis of bed hydrodynamics. The results show that particle size distribution enhances fluidization quality and that significant axial segregation is observed only in the case of wide PSD. The study provides insights into the role of PSD in gas fluidization and the similarities and differences between micro and large fluidized beds.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Chemical
Kaiqiao Wu, Shuxian Jiang, Victor Francia, Marc-Olivier Coppens
Summary: In rectangular and cylindrical annular fluidized beds, pulsating gas flow can create regular bubble patterns, overcoming challenges seen in conventional units. This study provides new opportunities for modularization of fluidized bed operations.
Article
Engineering, Environmental
Xi Gao, Jia Yu, Liqiang Lu, Cheng Li, William A. Rogers
Summary: A new SuperDEM-CFD coupled model was developed for simulating the hydrodynamics of non-spherical particles in fluidized beds. The model includes algorithms for modeling and distributing non-spherical particles, as well as drag models that consider particle orientation and cell voidage effects. Experimental validation was conducted, and large-scale simulations demonstrated the solver's capabilities for industrial-relevant flows.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Chemical
Salma Benzarti, Hatem Mhiri, Philippe Bournot
Summary: Fluidized beds have been crucial in processing industries for almost a century. However, their scaling up has been hindered by complex hydrodynamic behavior and diverse solids handling. This study simulated the hydrodynamic behavior of a 2D circulating fluidized bed under different superficial gas velocities and found that the gas/solid feeding configuration significantly affects the flow structure.
Article
Chemistry, Analytical
Atta Ullah, Muhammad Bilal Shabbir, Muhammad Umair, Muhammad Nadeem, Feng Xin
Summary: This study investigates the hydrodynamics of particle clusters and gas bubbles in fluidized beds using Digital Image Analysis and Transient Two Fluid Modeling. The results demonstrate that this approach aligns well with existing data and provides an alternative to costly experimentation for developing universal cluster size correlations.
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
(2021)
Article
Engineering, Environmental
Laurien A. Vandewalle, Victor Francia, Kevin M. Van Geem, Guy B. Marin, Marc-Olivier Coppens
Summary: Adequate use of gas pulsation can create an ordered and dynamically structured bubble flow in a bed of Geldart B particles, leading to a more homogeneous, controllable, and scalable bed. The structured bed exhibits significant differences in solid circulation and mixing behavior compared to a traditional fluidized bed, with mixing driven by advection rather than diffusion. Compartmentalization in the structured bed decouples the time scales of micro- and macromixing, providing tight control of mixing and narrower stress distribution in the solid phase compared to traditional devices.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Chemical
Lixiang Zhong, Dandan Xu, Yiyang Jiang, Yu Guo
Summary: Gas-fluidized beds of wet flexible fibers are investigated using a coupled approach of Discrete Element Method (DEM) and Computational Fluid Dynamics (CFD). The effects of cohesion and fiber flexibility on fluidization characteristics are examined. It is found that cohesion and fiber flexibility affect the pressure drop, minimum fluidization velocity, and solids mixing rate.
Article
Engineering, Chemical
Victor O. Ferreira, Toni El Geitani, Daniel Silva Junior, Bruno Blais, Gabriela C. Lopes
Summary: In this study, the accuracy of the unresolved CFD-DEM method was evaluated by comparing simulated and experimental results of a pilot-scale cylindrical liquid-solid fluidized bed. Different densities of particles were used to test various flow regimes. The comparison between experimental and simulated particles' dynamics revealed the importance of the Saffman lift force in predicting particle dispersion and preventing unphysical plumes. The results showed that the unresolved CFD-DEM method is valid for simulating liquid-solid fluidized beds.
Article
Engineering, Chemical
Liyan Sun, Kun Luo, Jianren Fan
Summary: A circulating fluidized-bed reactor for methanation was studied numerically, showing its feasibility and advantage in the methanation process. The reactor can be used effectively with higher temperatures for better product selectivity.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Engineering, Environmental
Alberto J. Orozco-Jimenez, Daniel A. Pinilla-Fernandez, Victor Pugliese, Antonio Bula, Patrice Perreault, Arturo Gonzalez-Quiroga
Summary: Gas-solid vortex chambers are a promising alternative for processes requiring enhanced heat and mass transfer rates. This study derives a model based on the conservation of angular momentum to understand the formation of a rotating solids bed. The model is validated using experimental data and can be used for analyzing and comparing gas-solid vortex typologies.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Victor Francia, Kaiqiao Wu, Marc-Olivier Coppens
Summary: Friction plays a key role in the stability of structured bubble flow in gas-solid fluidized beds. As friction decreases, solid-like regions widen, bubbles grow and ultimately break up the structure. CFD-DEM simulations show qualitative differences in bubble shape and acceleration, highlighting the need for further research on the effects of other particle properties, polydispersity, and domain size.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Mechanics
Wan-Long Ren, Yan Zhang, Xu-Hui Zhang, Xiao-Bing Lu
Summary: This paper uses an optimized Euler-Lagrange method to study the characteristics and formation mechanisms of layer inversion in binary liquid-solid fluidized beds with coarse particles. Through qualitative and quantitative analysis, the underlying mechanisms of layer inversion with coarse particles are revealed, providing important insights for understanding the dynamic behavior of fluidized beds.
Review
Engineering, Chemical
Zhennan Han, Junrong Yue, Sulong Geng, Dandan Hu, Xuejing Liu, Sabo Bello Suleiman, Yanbin Cui, Dingrong Bai, Guangwen Xu
Summary: Gas-solid micro fluidized beds exhibit unique characteristics and operating conditions, with various flow regimes discussed based on superficial gas velocity ratios. The study proposes a quantitative criterion to distinguish micro and macro fluidized beds, and develops correlations for different flow regimes in micro fluidized beds. Generalized fluidization maps applicable to micro fluidized beds are also proposed based on the developed correlations, identifying uncertainties and contradictories in reported data for guiding future studies.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Environmental
Shaotong Fu, Limin Wang
Summary: A new algorithm called unresolved LBM-DEM is proposed for discrete particle simulation. It combines lattice Boltzmann method (LBM) for fluid phase and discrete element method (DEM) for particle phase, with immersed moving boundary (IMB) used for gas-solid coupling. The method has advantages in resolving Geldart A particles and computational efficiency, with GPU parallel computation implemented. Validation tests showed good agreement with experimental data and one to two orders of magnitude speed up compared to traditional algorithms. This suggests unresolved LBM-DEM as a promising strategy for fluidization and multiphase flows.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Qiang Guo, Christopher M. Boyce
Summary: Bubble dynamics in gas fluidized beds are mathematically chaotic and difficult to predict. Various methods have been proposed to alter the bubble dynamics for specific processes. It has been shown that pulsed gas flow and vibration can transform the chaotic motion of gas bubbles into a structured pattern. This structured bubbling pattern is independent of the system width.
Article
Computer Science, Interdisciplinary Applications
A. Zare, H. Emdad, E. Goshtasbirad
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS
(2018)
Article
Engineering, Chemical
K. Hashemnia, S. Pourandi
Article
Materials Science, Characterization & Testing
Reza Roohi, Homayoun Emdad, Khosrow Jafarpur, Mohammad Reza Mahmoudi
JOURNAL OF TESTING AND EVALUATION
(2020)
Article
Mechanics
Kamyar Hashemnia, Omid Askari
MECHANICS RESEARCH COMMUNICATIONS
(2019)
Article
Engineering, Chemical
Amir Menbari, Kamyar Hashemnia
CHEMICAL ENGINEERING SCIENCE
(2019)
Article
Engineering, Chemical
Amir Menbari, Kamyar Hashemnia
Article
Engineering, Chemical
Kamyar Hashemnia
Article
Engineering, Multidisciplinary
Y. Amini, H. Emdad, M. Farid
Article
Biology
Mohsen Motie Shirazi, Omid Abouali, Homayoun Emdad, Mohammadreza Nabavizadeh, Hossein Mirhadi, Goodarz Ahmadi
COMPUTERS IN BIOLOGY AND MEDICINE
(2017)
Article
Computer Science, Interdisciplinary Applications
Ebrahim Ghahramani, Omid Abouali, Homayoon Emdad, Goodarz Ahmadi
COMPUTERS & FLUIDS
(2017)
Article
Multidisciplinary Sciences
Asghar Farhadi, Ebrahim Goshtasbi Rad, Homayoun Emdad
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2017)
Article
Engineering, Multidisciplinary
Y. Amini, H. Emdad, M. Farid
Article
Engineering, Chemical
Yongxiang Wu, Nguyen Thi Hong Nhung, Deqian Zeng, Nengneng Luo, Akira Otsuki, Gjergj Dodbiba, Toyohisa Fujita
Summary: This study proposed a novel method for synthesizing flower-like vaterite calcium carbonate using nanobubble-containing ethanol and water mixed solution as the solvent and discussed the formation mechanism of vaterite with different shapes. The synthesized vaterite has significant practical interest in the integrated treatment of wastewater contaminated by heavy metals with effective Cd(II) removal, providing a promising field for studying heavy metal and pollutant adsorption in the liquid phase.
ADVANCED POWDER TECHNOLOGY
(2024)
Article
Engineering, Chemical
Jian Gong, Lipo Cheng, Ming Liu, Jie Jiang, Xiaoduo Ou
Summary: This study investigates the effects of particle shape on the collapse of granular columns using the discrete element method. The results show that particle shape has a significant impact on deposition morphology, energy evolution, and mechanical coordination number. Sphericity and angularity are identified as the most important macroscale factors, while roughness has a weaker microscale influence.
ADVANCED POWDER TECHNOLOGY
(2024)