Article
Engineering, Chemical
Pavitra Singh, Pankaj Kalita, Pinakeswar Mahanta, Plabon Tamuly
Summary: The SL-GSVR vortex reactor shows high heat and mass transfer efficiency, making it suitable for pharmaceutical and food processing industries, especially in food grain drying and preservation. Comparison between numerical and experimental results indicates improved bed uniformity, reduced system cost and complexity, as well as enhanced product quality in the SL-GSVR reactor.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(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
Engineering, Chemical
Tian Nan, Jesse Zhu, Dominic Pjontek, Salah Srabet, Haohao Zhou
Summary: The hydrodynamics of an IGLSCFB were studied, and the results showed that the gas and solids holdups in the bed were uniform under lower gas and liquid velocities, but became non-uniform at higher velocities. The gas holdup increased with gas and liquid velocities, while the solids holdup increased with solids circulation rate and gas velocity, but decreased with liquid velocity.
Article
Thermodynamics
Pavitra Singh, Pinakeswar Mahanta, Pankaj Kalita
Summary: This study focuses on enhancing fluidization capacity and optimizing a lab-scale gas-solid vortex reactor without-slit numerically. By increasing the length to diameter ratio (L/D) from 0.2 to 1.2, the reactor capacity of the lab-scale GSVR reactor was significantly enhanced.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Engineering, Environmental
Chunhua Zhang, Bona Lu, Wei Wang, Mengxi Liu, Chunxi Lu, Mao Ye
Summary: In this study, a population balance model (PBM) combined with multiscale computational fluid dynamics (CFD) was used to simulate the evolution of coke distribution in a methanol-to-olefins fluidized bed reactor. The predicted wide and uneven distribution of coke content showed good agreement with experimental data. The mass fractions of the desired products, ethylene and propylene, and their selectivity ratio were also well predicted. The reasonable prediction suggests that coupling PBM with multiscale CFD is helpful to understand and optimize MTO reactors.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Thermodynamics
Pavitra Singh, Pinakeswar Mahanta, Pankaj Kalita
Summary: The main objective of this study is to develop a best-performing gas-solid vortex reactor (GSVR) dryer and compare the effect of spiral versus conical chimney outlet on capacity enhancement. The computational fluid dynamics analysis showed that the solid loading capacity of the GSVR with a spiral chimney is 27% higher than that with a conical chimney. Additionally, capacity enhancement appears to be simpler and easier with a spiral chimney outlet due to its symmetric nature of construction.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
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, Chemical
Jingwei Geng, Yujie Tian, Wei Wang
Summary: In this work, a two-level averaging approach is proposed for mesoscale drag modeling in gas-solid fluidization. The method defines the mean drag at the fine-grid scale and the unified EMMS drag at the coarse-grid scale by performing a series expansion with respect to the phase mean points. The effectiveness of the method is validated through comparisons with simulations at different scales.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Chemical
Frederik Zafiryadis, Anker Degn Jensen, Weigang Lin, Elisabeth Akoh Hove, Morten Boberg Larsen, Hao Wu
Summary: This study utilizes the Eulerian-Lagrangian multiphase particle-in-cell method to simulate the injection of a gas-liquid spray into a gas-solid fluidized bed. The model accurately predicts the gas temperature distribution within the injection region, but discrepancies may arise due to the presence of wet particle agglomerates in the spray region.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Engineering, Chemical
Julia Picabea, Mauricio Maestri, Miryan Cassanello, Gabriel Salierno, Cataldo De Blasio, Maria Angelica Cardona, Daniel Hojman, Hector Somacal
Summary: The study focused on implementing time series analysis tools to validate LSFB modeling, showing that the simulation can capture LSFB behavior. Trends of solid dispersion coefficients and mixing times predicted by the simulation are in good agreement with the experiments.
Article
Engineering, Environmental
Florian Wery, Laurien A. Vandewalle, Guy B. Marin, Geraldine J. Heynderickx, Kevin M. Van Geem
Summary: Process intensification in gas-solid fluidization processes can be achieved by working in a centrifugal rather than a gravitational field. The gas-solid vortex unit (GSVU) is an ideal candidate for heterogeneously catalyzed processes. A four-way coupled CFD-DEM model describing the hydrodynamics in the GSVU with an unprecedented level of detail is validated using experimental data, and it demonstrates enhanced heat and mass transfer rates and a narrow gas-phase residence time distribution.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Lin Wang, Jesse Zhu, George Nakhla, Yuanyuan Shao
Summary: This study investigated the hydrodynamic characteristics of liquid-solid and gas-liquid-solid inverse fluidized beds with bare particles and particles with biofilm. The presence of biofilm was found to increase the fluidizability of the bed layers, suggesting an improvement in the fluidization behavior.
ADVANCED POWDER TECHNOLOGY
(2021)
Article
Engineering, Environmental
Mohammad Shakil Ahmmed, Mads Borgbjerg Jensen, Michael V. W. Kofoed, Lars D. M. Ottosen, Damien J. Batstone
Summary: The addition of hydrogen to anaerobic digesters for biomethane production is a promising technique, but its success relies heavily on efficient gas-liquid transfer. A computational fluid dynamic model was developed to simulate gas-liquid dynamics during hydrogen injection, highlighting the importance of gas flow and bubble size. The study showed that increasing gas flow may not effectively reduce inactive zones in digesters, and that smaller bubble sizes resulted in higher gas-liquid mass transfer rates.
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
Su Meixuan, Wang Zhigiang, Wang Jinjun, Li Guofeng
Summary: The study investigates particle charge in a cyclone tribocharger using a CFD-DEM modeling approach, which simulates and predicts CaCO3 particle charge under different gas velocities, particle sizes, and moving distances. The results show the quantitative and qualitative relationship between different parameters and the charge-to-mass ratio is compared with experimental results, yielding values in the magnitude of 10(-4).
Article
Engineering, Chemical
Li Ge Wang, Ruihuan Ge, Xizhong Chen
Summary: This paper presents a thorough study of particle impact breakage in selection function with a unified breakage criterion. The lack of a unified breakage criterion disables a direct comparison of particle breakage propensity, but a novel computational modelling workflow is proposed to address this issue. The value of digital twin in substantially reducing the experimental trials is highlighted.
Article
Materials Science, Multidisciplinary
Xizhong Chen, Di Peng, John P. Morrissey, Jin Y. Ooi
Summary: This paper discusses the application of bonded contact models in the discrete element method and identifies two fundamental types of bond models. The strength and weakness of these models are assessed through cantilever beam bending simulation cases.
Review
Engineering, Chemical
Li-Tao Zhu, Xi-Zhong Chen, Ouyang Bo, Wei-Cheng Yan, He Lei, Zhe Chen, Zheng-Hong Luo
Summary: Artificial intelligence (AI), machine learning (ML), and data science are leading to a promising transformative paradigm. ML, especially deep learning and physics-informed ML, is a valuable toolkit that complements incomplete domain-specific knowledge in conventional experimental and computational methods. ML can provide flexible techniques to facilitate the conceptual development of new robust predictive models for multiphase flows and reactors by finding hidden pattern/information/mechanism in a data set.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Engineering, Chemical
Bo Ouyang, Li -Tao Zhu, Zheng-Hong Luo
Summary: This study proposes a machine learning-based acceleration mode to improve the computational efficiency of highly resolved simulations for gas-particle flows. By training artificial neural networks and long short-term memory models, it is possible to accurately predict the flow field. Combining this method with traditional computational fluid dynamics, the time-series highly resolved flow fields can be approximated within a 1% error, while saving 40% of the computing time.
Article
Engineering, Chemical
Hui-Long Wei, Bo Ouyang, Li-Tao Zhu, Yuan-Hai Su, Zheng-Hong Luo
Summary: This study investigated the reaction network and kinetic characteristics of the oxidation of cyclohexanone with nitric acid through machine learning model and target factor analysis. The results provide valuable insights into the oxidation process under various operational conditions.
Article
Engineering, Chemical
Bo Ouyang, Litao Zhu, Zhenghong Luo
Summary: The present study applies several novel data-driven analysis approaches to extract human-understandable insights from machine learning-based meso-scale closure in fluid-particle flows. The study aims to quantitatively investigate the influence of flow properties on mesoscale drag correction (Hd), and the results show strong correlations between the features (i.e., slip velocity (u* sy) and particle volume fraction (es)) and the label Hd. The interpretable ML analysis confirms this conclusion and quantifies the contribution of u* sy, es, and gas pressure gradient to the model.
Article
Engineering, Chemical
He Lei, Li -Tao Zhu, Zheng-Hong Luo
Summary: Detailed studies on the effect of cohesiveness on the hydrodynamics, heat transfer, and reaction characteristics in high-temperature polymerization fluidized bed reactors have been rarely reported. This work establishes a CFD-DEM approach coupled with a solid bridge force model and polymerization reaction kinetics model to simulate the reactive gas-solid flows with cohesive particles. The results show that cohesive particle agglomeration significantly affects the concentration, velocity fields, and temperature distribution in the reactor. The model also reveals the influence of cohesion model parameters on the onset temperature and severity of particle agglomeration.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Ya-Nan Yang, Hui Liu, Li-Tao Zhu, Jie Jin, Xi-Bao Zhang, Zheng-Hong Luo
Summary: Multizone circulating reactor (MZCR) technology is an advanced olefin polymerization process that enables the production of polyolefins with varying properties. This study proposes a multimodel coupling method to understand the gas-phase propylene polymerization in a MZCR. The developed model considers the molecular and particle properties of polypropylene and examines key operating variables related to product properties. The simulation results show that the MZCR technology allows for a wide range of polymer properties.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Engineering, Chemical
Lianzhen Zhang, Li Ge Wang, Yin Wang, Yi He, Xizhong Chen
Summary: This paper validates the particle impact breakage model, Vogel and Peukert model, with a focus on the impact number. The model is widely used in various fields but rarely studied in the application of repeated impact. The results show that the model is generally applicable to all breakage cases considering the impact number, and the effect of impact number is further explored through population balance model and Discrete Element Method simulation.
Article
Energy & Fuels
Wendong Yang, Xianxian Lv, Lige Wang, Di Peng, Xizhong Chen
Summary: This paper presents a novel numerical approach for simulating hydraulic fracturing processes using the Edinburgh bonded particle model coupled with computational fluid dynamics. The model considers the fracture propagation law under different principal stress differences and investigates the fracture propagation mechanism of two-hole synchronous hydraulic fracturing. The results demonstrate that the arrangement and spacing of two holes significantly influence the complexity of hydraulic fractures, and the principal stress difference becomes more prominent in the direction of fracture propagation with increasing principal stress difference.
GEOMECHANICS AND GEOPHYSICS FOR GEO-ENERGY AND GEO-RESOURCES
(2023)
Article
Engineering, Chemical
Ouyang Bo, Li-Tao Zhu, Zhao-Quan Wen, Xizhong Chen, Zheng-Hong Luo
Summary: In this study, a big data approach is used to analyze approximately 10^8 data points for drag coefficient (F-d) of Geldart Group A particles at atmospheric pressure. It is found that the contribution of particle Reynolds number (Re-s) on F-d is much less than phase fraction (e). Therefore, the drag models are simplified to machine learning and conventional expressions only related to e. The simplified models achieve similar predictive performance as the originals and provide better numerical stability for coarse grid simulations.
Article
Engineering, Chemical
Li-Tao Zhu, Anthony Wachs
Summary: Researchers propose a microstructure-informed probability-driven point-particle (MPP) method to enhance the reliability of Euler-Lagrange simulations in particle-laden flows. However, the MPP model cannot be directly used due to computation limitations. To overcome this, an interpolated MPP (iMPP) method is introduced, which shows promising results in capturing hydrodynamic forces/torques fluctuations in a wide range of cases. This advancement contributes to the development of a more versatile closure model suitable for integration into Euler-Lagrange simulations.
Review
Engineering, Chemical
Sheng-lin Yan, Xu-qing Wang, Li-tao Zhu, Xi-bao Zhang, Zheng-hong Luo
Summary: This review comprehensively analyzes the kinetics of bubble behaviors and the mechanisms of gas-liquid mass transfer. It discusses the correlations between bubble behavior and mass transfer, as well as modeling approaches. The impact of global and local turbulence on bubble behavior and mass transfer is also discussed.
CHEMICAL ENGINEERING SCIENCE
(2023)
Review
Engineering, Chemical
Shi-Jiao Li, Li-Tao Zhu, Xi-Bao Zhang, Zheng-Hong Luo
Summary: Phase change is widely used in various fields such as chemical engineering, energy, electronics, vehicle, and space exploration. Understanding the intricacies of multiphase flow processes with heat and mass transfer due to phase change is crucial. Computational fluid dynamics (CFD) has been increasingly applied as an effective tool to analyze phase change processes, enhance understanding and optimize effects. This review provides a comprehensive overview of CFD methodologies in simulating phase change flows in different applications and discusses the challenges and prospects in facilitating the application of phase change flow.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Engineering, Chemical
Li-Tao Zhu, He Lei, Bo Ouyang, Zhao-Quan Wen, Ya-Nan Yang, Zheng-Hong Luo
Summary: This study introduces the concepts of 'multi-level-nozzle' and 'continuous oscillatory tapered' fluidized beds to enhance contact efficiency and promote mixing between the gas and particle phases in a turbulent fluidized bed. The feasibility of these concepts is assessed through experimental and modeling evaluations. By designing multiple experimental cases, the influence of injection nozzle numbers, heights, angles, and reactor shapes on the hydrodynamic mechanisms is systematically investigated. The implementation of these conceptual designs leads to improved flow quality by enhancing particle intermittency and achieving higher oscillation frequencies.
Article
Engineering, Chemical
Ri Zhang, Shasha Zhang, Mengyan Ding
Summary: A thin liquid film method is proposed to evaluate sand erosion in annular flow. This method considers the direct interaction between the liquid film and gas core, as well as the entrainment and deposition of droplets. The erosion rate is calculated by considering the effects of liquid entrainment and particle velocity decay. The method is fully verified by comparing with experimental data.
Article
Engineering, Chemical
Yu Suo, Xianheng Su, Wenyuan He, Xiaofei Fu, Zhejun Pan
Summary: This research investigates the mechanical properties of sandstone-shale composite through orthogonal experimental method and discrete element simulation. The results show that different lithologies and thickness ratios can affect the strength and fracture mode of the composite rock samples.
Article
Engineering, Chemical
Maurizio Troiano, Andrea El Hassanin, Roberto Solimene, Alessia Teresa Silvestri, Fabrizio Scala, Antonino Squillace, Piero Salatino
Summary: This study investigates the potential of Fluidized Bed Finishing (FBF) for square flat AlSi10Mg specimens manufactured via Laser-Powder Bed Fusion (L-PBF) additive manufacturing technology. The results show that good finishing can be achieved using rotation-assisted tests, with a maximum reduction of surface roughness by 67%. Steel particles are found to be the most effective bed material.
Review
Engineering, Chemical
Ningbo Song, Wanzhong Yin, Jin Yao
Summary: Seawater's dissolved salts and minerals have various effects on the flotation process, including influencing the characteristics and behavior of flotation factors, as well as affecting the surface of sulfide minerals. In most cases, seawater has adverse effects on the flotation of sulfide minerals, but these effects can be mitigated by adjusting the reagents.
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, Chemical
Shuo Li, Huili Zhang, Jan Baeyens, Miao Yang, Zehao Li, Yimin Deng
Summary: The paper assesses the behavior of cohesive Geldart C-type particles when fluidized by air with the aid of vibration. It determines that mechanical vibration is a simple and effective method to improve the fluidity of cohesive particles during fluidization.
Article
Engineering, Chemical
Zhenfei Feng, Qingyuan Zhang, Shanpan Liang, Zhenzhou Li, Fangwen Guo, Jinxin Zhang, Ding Yuan
Summary: A new micro/mini-channel heat sink (MCHS) with a combined structure of longitudinal and transverse vortex generators is designed, using Al2O3 nanofluid as the working medium. The study explores the effects of transverse vortex generator shape and longitudinal vortex generator angle on the hydraulic and thermal characteristics, comprehensive performance, entropy generation, and exergy efficiency. The results show that the triangular transverse vortex generator improves the comprehensive performance and exergy efficiency. Combined with the longitudinal vortex generator, the MCHS achieves the best comprehensive performance, entropy generation, and exergy efficiency when the Reynolds number is 742.
Article
Engineering, Chemical
Kostas Giannis, Christoph Thon, Guoqing Yang, Arno Kwade, Carsten Schilde
Summary: This study presents a 3D convolutional neural network (3D-CNN) methodology for generating realistic 3D models of particles. The method trains on 2D projections of particle images to predict their 3D shapes, and evaluates the accuracy of the predictions using Fourier shape descriptors (FSDs). This methodology has wide applications in particle shape analysis.
Article
Engineering, Chemical
Zheng-qing Zhou, Lu-jia Chai, Yu-long Zhang, Ya-bin Wang, Ze-chen Du, Tian-yi Wang, Yu-zhe Liu
Summary: The dynamic oxidation and shell-breaking processes of aluminum nanoparticles (ANPs) during heating were studied using in situ transmission electron microscopy. The results revealed that the changes in shell thickness can be divided into three stages, and the active aluminum content of ANP decreased before shell-breaking.
Article
Engineering, Chemical
Fulei Chen, Huaqing Ma, Zihan Liu, Lianyong Zhou, Yongzhi Zhao
Summary: A particle breakage model based on the particle replacement scheme, using the polyhedral model to describe particles, is proposed in this work to accurately describe the breakage of a large number of particles. Additionally, a fast-cutting algorithm is proposed to reproduce the size distribution of progeny particles determined by the breakage model. The validation and simulation results show satisfactory accuracy, efficiency, and stability of the algorithm.
Review
Engineering, Chemical
Matteo Errigo, Christopher Windows-Yule, Massimiliano Materazzi, Dominik Werner, Paola Lettieri
Summary: Gas-solid fluidized-bed systems have advantages in terms of chemical reaction efficiency and temperature control, making them widely used in industrial applications. However, the design, scale-up, and optimization of these complex units are limited by the lack of deep physical understanding. Non-invasive and non-intrusive diagnostic techniques provide a way for researchers to study these systems without affecting the flow field or directly contacting the medium under study.
Article
Engineering, Chemical
Saeed Fateh, Mohammad Behshad Shafii, Mohammad Najafi, Cyrus Aghanajafi
Summary: Applying a magnetic field to ferrofluids alters their flow characteristics and enhances heat transfer. Through visualization and quantitative investigation, it is found that the magnetic field influences the flow patterns and velocity profiles, improving fluid mixing and vorticity magnitude.
Article
Engineering, Chemical
Lei Gao, Bingbing Wei, Xiaochuan Hu, Zaifeng Yao, Yiwen Fang, Xuejian Gao
Summary: In this study, a numerical model of sand triaxial test was established using discrete element software PFC3D, and an indoor triaxial test was conducted to calibrate the numerical model. The influence of microscopic parameters on the macroscopic mechanical response of sand was analyzed. The results showed that the friction coefficient had the greatest impact on the peak strength and residual strength of the sand's stress-strain curve, and it was positively correlated. The normal tangential stiffness ratio was negatively correlated, while the porosity and boundary flexibility stiffness had minimal influence on it.
Article
Engineering, Chemical
Xuan Liu, Jie Gong, Kai Jiang, Xiaojuan Lai, Yu Tian, Kang Zhang
Summary: This study aimed to improve the performance of lignite coal water slurries (CWSs) by synthesizing a series of three-arm amphiphilic block copolymers. By controlling the relative molecular weight, hydrophilic/hydrophobic ratio, and ionic group content, the apparent viscosity of CWSs was significantly reduced and the static stability was improved. Thermogravimetric testing and XPS analysis were conducted to reveal the mechanism behind the improved performance.
Article
Engineering, Chemical
Lanka Dinushke Weerasiri, Daniel Fabijanic, Subrat Das
Summary: Fluidization at low pressure offers significant benefits for the fine chemical industry. This study investigates the behavior of bubbles and bed expansion under low pressure conditions. It is found that lower pressure leads to larger bubbles, increased bubble quantity, and higher aspect ratio. The predictability is affected by the inhomogeneous fluidization, but low pressure fluidization can generate similar bubble sizes with lower fluidizing mass compared to atmospheric pressure.