Article
Engineering, Chemical
Muhammad Adnan, Jie Sun, Nouman Ahmad, Jin Jia Wei
Summary: The study compared the performance of Eulerian-Eulerian and Eulerian-Lagrangian numerical approaches in describing the hydrodynamic behavior of a pilot-scale bubbling bed reactor. The sub-grid drag correction based on the energy minimization and multiscale theory was found to be the key modeling parameter for both models. Both models predicted similar hydrodynamics behavior, with TFM achieving better accuracy in terms of axial and radial solids concentration profiles. The grid size analysis showed that DDPM generated a better grid-independent solution than TFM, making it a suitable candidate for large-scale industrial applications on coarser grids. Other parameters like time-step, time-averaging interval, specularity coefficient, restitution coefficient, reflection coefficient, and numbers of parcels had minor effects on the overall hydrodynamics behavior of the reactor.
Article
Engineering, Chemical
Jingwei Geng, Zhuo Yang, Yujie Tian, Bona Lu, Wei Wang
Summary: To investigate the effects of macroscale constraints on fluidization, fine-grid simulations were used to compare the periodic domain and realistic bed. The differences were highlighted by examining force balance conditions in the gas-phase, solid-phase, and mixture. The influence of the bounding wall was implicitly included through markers such as gas-phase pressure gradient and turbulent kinetic energies.
CHEMICAL ENGINEERING SCIENCE
(2023)
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
Muhammad Adnan, Jie Sun, Nouman Ahmad, Jin Jia Wei
Summary: This study systematically investigated the verification and validation of the DDPM approach for different gas-solid fluidization regimes, including bubbling, turbulent, and circulating fluidized beds. The results showed that the sub-grid correction based on the EMMS approach is essential for accurately accounting for the effects of dissipative structures in all three fluidization regimes.
Article
Engineering, Chemical
Yunpeng Jiao, Jianhua Chen
Summary: The study introduced a gradual drag correlation based on the GL-EMMS model, successfully integrated into the E-E and E-L frameworks. A simplified meshing treatment at the inlet boundary effectively reduced the computing load. The E-E simulation predicted the total gas holdup and the radial distribution of liquid velocity well, with some noticeable deviations observed in certain cases.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2021)
Article
Engineering, Environmental
Shanwei Hu, Xinhua Liu
Summary: This study utilized the population balance model (PBM) and energy-minimization multi-scale (EMMS) model to describe the hydrodynamics of gas-solid bubbling fluidized beds, incorporating both models into a coupled simulation scheme to predict bed expansion characteristics and solid velocities. The results were validated through comparison with experimental data, showing satisfactory agreement between measured and simulated bubble size distributions. The proposed sub-grid drag model and coupled simulation scheme are effective in capturing the salient features of gas-solid bubbling fluidized beds hydrodynamics.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Chemical
Nouman Ahmad, Jianqiang Deng, Muhammad Adnan
Summary: This article investigates the effects of different bubble diameter correlations on the multiscale bubbling drag model and proposes a modification to the model for improved computational fluid dynamics simulations of bubbling and turbulent fluidized beds.
CHINESE JOURNAL OF CHEMICAL ENGINEERING
(2022)
Article
Engineering, Chemical
Zhuo Yang, Bona Lu, Wei Wang
Summary: In this study, a generic EMMS drag model was developed using Artificial Neural Network (ANN) to simulate dense fluidized beds under a wide range of operating conditions and material properties. The model's algorithm was optimized to efficiently provide a large dataset and the performance of ANN was tested by training with different numbers of data and hidden layer structures. The EMMS-ANN model showed reasonable prediction and good applicability to a wide range of dense fluidization.
CHEMICAL ENGINEERING SCIENCE
(2021)
Article
Engineering, Chemical
Lingkai Kong, Ji Xu, Junwu Wang, Wei Ge
Summary: Clusters in gas-solid suspensions were identified and their properties were quantified using the probe method, the DBSCAN-based method, and the Voronoi-based method. The probe method showed comparable structural properties to the other two particle-based methods, while the particle-based methods provided more insights into the clusters' fractal dimension, shape, and topology. The DBSCAN algorithm, however, had the potential of introducing ambiguity in identifying the dense phase. Dynamic analysis using the Voronoi-based method revealed the existence of two characteristic lifetimes of clusters and the combined effect of growth, detachment, coalescence, and breakage in the cluster's evolution. Quantitative analysis of these processes is crucial in cluster dynamics modeling.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Engineering, Chemical
Shanwei Hu, Xinhua Liu
Summary: The importance of bubble dynamics in fluidized beds has been highlighted by extensive experimental and numerical studies. However, previous coarse-grid CFD models have neglected the bubble dynamic evolution and its effects on sub-grid closures, especially for Geldart A particles. In this article, a population balance model with improved kernels was used to describe the bubble dynamic evolution in three-dimensional bubbling beds. The simulation results showed that the model can accurately predict the hydrodynamics and heterogeneous structures in three-dimensional bubbling beds of fine particles.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Engineering, Chemical
Yuelin Yang, Quan Zhang, Teng Pan, Yue Qu, Xiaolong Liu, Xi Li, Youwei Cheng, Lijun Wang, Weiliao Liu
Summary: This study thoroughly investigated the hydrodynamics of low-density particles in a turbulent fluidized bed and optimized the calculation process of the EMMS model. It provides a research model and guidance for the design of industrial fluidized bed reactors using low-density particles.
Article
Engineering, Chemical
Yujie Tian, Jingwei Geng, Wei Wang
Summary: This research introduces a two-step scheme to reflect on the choice of markers in the classic experimental approach, and deduces the definitional relations of the drag correction factor from force balance equations. A comparison between common drag models and definitional relations shows that correlating the heterogeneity index or drift velocity with certain parameters cannot address the challenge of developing a general mesoscale drag model.
Article
Engineering, Electrical & Electronic
Tian Tian, Lingling Li, Weitao Chen, Huabing Zhou
Summary: Deep learning has greatly improved remote sensing image scene classification, with SEMSDNet showing superior performance and efficiency through multiscale dense networks and squeeze-and-excitation attention mechanism.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2021)
Article
Engineering, Chemical
Mona Mary Varghese, Teja Reddy Vakamalla, Bhargav Mantravadi, Narasimha Mangadoddy
Summary: Different drag models were used to predict bubbling and turbulent fluidized-bed characteristics, showing close agreement with experimental results in terms of bubble shape and pressure drop, but overestimating pressure drop at low gas velocities.
CHEMICAL ENGINEERING & TECHNOLOGY
(2021)
Article
Engineering, Environmental
Haoliang Wang, Biyu Zhang, Xiangyang Li, Yiting Xiao, Chao Yang
Summary: In this study, a new procedure is developed to model drag force on particles in dense systems using inline experimental measurements. The newly developed model shows excellent characteristics in predicting flow field, solid holdup distributions, and maintaining mass conservation compared to other commonly used models. Further studies are needed to quantitatively explain the evaluation results.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Rong Ma, Jie Sun, Dong Hui Li, Jin Jia Wei
JOURNAL OF CATALYSIS
(2020)
Review
Thermodynamics
Sun Jie, Zhang Zhi, Wang Li, Zhang Zhenwen, Wei Jinjia
JOURNAL OF THERMAL SCIENCE
(2020)
Article
Engineering, Chemical
Muhammad Adnan, Jie Sun, Nouman Ahmad, Jin Jia Wei
Summary: This study systematically investigated the verification and validation of the DDPM approach for different gas-solid fluidization regimes, including bubbling, turbulent, and circulating fluidized beds. The results showed that the sub-grid correction based on the EMMS approach is essential for accurately accounting for the effects of dissipative structures in all three fluidization regimes.
Article
Chemistry, Multidisciplinary
Jin Huan Pu, Si Kun Wang, Jie Sun, Wen Wang, Hua Sheng Wang
Summary: Molecular dynamics simulations were used to study how to maintain and enhance pure evaporation on nanopillar surfaces. It was found that closer nanopillar spacing and larger diameter enhance evaporation but increase the likelihood of boiling, while shorter nanopillar height enhances evaporation and suppresses boiling. Additionally, maintaining a nanofilm thickness above a certain threshold is necessary to avoid the suppression effect on evaporation.
Article
Engineering, Chemical
Muhammad Adnan, Jie Sun, Nouman Ahmad, Jin Jia Wei
Summary: The study compared the performance of Eulerian-Eulerian and Eulerian-Lagrangian numerical approaches in describing the hydrodynamic behavior of a pilot-scale bubbling bed reactor. The sub-grid drag correction based on the energy minimization and multiscale theory was found to be the key modeling parameter for both models. Both models predicted similar hydrodynamics behavior, with TFM achieving better accuracy in terms of axial and radial solids concentration profiles. The grid size analysis showed that DDPM generated a better grid-independent solution than TFM, making it a suitable candidate for large-scale industrial applications on coarser grids. Other parameters like time-step, time-averaging interval, specularity coefficient, restitution coefficient, reflection coefficient, and numbers of parcels had minor effects on the overall hydrodynamics behavior of the reactor.
Article
Thermodynamics
Li Wang, Jie Sun, Zhi Zhang, Jin Jia Wei
Summary: A trans-dimensional multi-physics coupled analysis method is proposed to predict the global performance and accurately quantify the local deformation of the heat collection element in concentrated solar power plants. Different worst scenarios are identified in different sections of the loop, highlighting the importance of considering practical installation errors and the interaction between HCE and concentrator.
APPLIED THERMAL ENGINEERING
(2021)
Article
Engineering, Chemical
Muhammad Adnan, Jie Sun, Nouman Ahmad, Jin Jia Wei
Summary: The study evaluates the hydrodynamics behavior of a 3D small-scale cold flow modeling of a gas-solid tapered fluidized bed using the Eulerian-Eulerian two-fluid modeling approach. The results show that the gas-particle drag force is crucial for resolving the correct time-averaged axial and radial solids holdup profiles, with the Gibilaro drag model offering the highest accuracy. Adjusting the particle-wall specularity coefficient and particle-particle restitution coefficient parameters can help achieve better agreement between experimental data and model results.
Article
Thermodynamics
Zhen Wen Zhang, Jie Sun, Rui Lin Wang, Jin Jia Wei
Summary: The study proposes a generalized model and unified expression for the ISCC system, revealing the effects of allocation and superposition on performance, ultimately providing theoretical guidance for future applications.
APPLIED THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Qili Xu, Jie Sun, Zehua Ma, Rui Xie, Jinjia Wei
Summary: This study comprehensively investigates the influences of variable porosity on the thermochemical energy storage characteristics in DHR/IHR. It is found that the variable porosity has dual competitive impacts on the reaction rate and temperature field, and the constant porosity assumption may lead to overestimation or underestimation of the performance.
APPLIED THERMAL ENGINEERING
(2022)
Article
Chemistry, Physical
Jin Huan Pu, Si Kun Wang, Jie Sun, Wen Wang, Hua Sheng Wang
Summary: The molecular dynamics simulation demonstrates that nanodroplets can self-jump off the nanostructured surface driven by Laplace pressure difference. The characteristics of the hydrophilic pinning site have competitive effects on the growth and jumping dynamics of nanodroplets. Increasing the size and wettability of the pinning site promotes droplet growth but blocks droplet self-jumping.
JOURNAL OF MOLECULAR LIQUIDS
(2021)
Article
Thermodynamics
Zhen Wen Zhang, Jie Sun, Dong Hui Li, Ma Rong, Jin Jia Wei
Summary: In this study, a novel modular photo-thermo-reactor (MPTR) is proposed for efficient and cost-effective hydrogen production from methanol steam reforming. The MPTR utilizes synergistic photo-thermo-catalysis (PTC) with Pt/CuO catalyst and thermo-catalysis (TC) with Cu/ZnO/Al2O3 catalyst in a cascade way using composite catalyst beds. A multiphysics model is established to optimally design the MPTR, covering optical, flow, thermal, and chemical sub-processes. The predicted performance indicates that the MPTR achieves the highest overall solar-to-hydrogen efficiency of 24.1% and annual hydrogen production of 1211 Nm(3)/m(2) in Xi'an, China.
ENERGY CONVERSION AND MANAGEMENT
(2022)
Article
Chemistry, Applied
Donghui Li, Jie Sun, Rong Ma, Jinjia Wei
Summary: This study proposes a novel technique using full-spectrum photo-thermo-catalysis for high-efficiency H2 production. The synergistic effect of intrinsic photon and thermal effects from full-spectrum sunlight is explored, resulting in improved H2 production performance. The Pt-CuOx photo-thermo-catalyst with Pt-Cu/Cu2O/CuO heterojunctions demonstrates both photoelectronic and photothermal conversion capabilities. The optimized reaction kinetics, including intensified intermediate adsorption and accelerated carrier transfer, contribute to the enhanced performance of solar-driven methanol steam reforming.
JOURNAL OF ENERGY CHEMISTRY
(2022)
Article
Chemistry, Physical
Rong Ma, Hui Su, Jie Sun, Donghui Li, Zhenwen Zhang, Jinjia Wei
Summary: The concentrated photo-thermo-catalysis (CPTC) technology enables full-spectrum solar harmonic conversion of urea-rich wastewater into hydrogen by regulating the spectral energy quantity and quality. This is achieved through catalyst structure optimization and expanded reaction pathways, resulting in a 50% enhanced performance compared to traditional photo-/thermo-catalysis.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Thermodynamics
Liming Wang, Yonggang Lei, Baocun Du, Yinshi Li, Jie Sun
Summary: This study proposes the use of elliptical fins to improve the thermal storage performance of a horizontal double tube latent thermal energy storage unit (HDT-LTESU). The addition of elliptical fins effectively improves convection heat transfer of the PCM, especially at the top and bottom of the annulus. High aspect ratio fins enhance the comprehensive performance of the system, with a maximum enhancement ratio of 16.9% for melting and 13.8% for solidification. The entransy theory also verifies the mechanism of enhanced thermal energy storage.
APPLIED THERMAL ENGINEERING
(2023)
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.
