Article
Chemistry, Physical
Vaibhav Sharma, Florent Fessler, Fabrice Thalmann, Carlos M. Marques, Antonio Stocco
Summary: Measuring the rotational and translational Brownian motion of single spherical particles can reveal dissipations due to particle-environment interaction. The experiments conducted in this article demonstrate the measurement of in-plane translational and rotational drag coefficients for a single spherical Brownian particle. These drag coefficients are influenced by particle size, particle-wall distance, and viscous dissipations. Measurements on Janus particles close to solid walls and lipid bilayer membranes reveal that particle-wall distance and size can be determined by hydrodynamic models for particles close to walls. For particles partially wrapped by lipid membranes, when there is no strong binding interaction, translational and rotational drags are significantly larger compared to non-wrapped particles. The dissipations in the deformed membrane cap region also contribute strongly to the drag coefficients.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Food Science & Technology
Mark Al-Shemmeri, Kit Windows-Yule, Estefania Lopez-Quiroga, Peter J. Fryer
Summary: The physicochemical transformation of coffee during roasting is affected by the time-temperature profile, which is in turn influenced by heat transfer mechanisms governed by particle dynamics. This study employed Positron Emission Particle Tracking (PEPT) to analyze the granular flow of coffee in a pilot-scale rotating drum roaster. The results revealed that the drum speed, batch size, and bean density significantly impact the particle dynamics within the system. These findings suggest that controlling the drum speed can modulate conductive heat transfer from the heated drum to the bean bed, thereby influencing the roasting process.
FOOD RESEARCH INTERNATIONAL
(2023)
Article
Engineering, Chemical
Shengqiang Jiang, Xue Long, Yixuan Ye, Jingang Liu, Shiping Yang, Xiangwu Xiao, Sisi Liu
Summary: This study establishes a similarity criterion for the particle motion behavior in large-scale industrial drums using dimensional analysis, and finds the mapping relationship between the particle movement trajectories and the drum's size and rotational speed. The results of this study are of great significance in solving the computational challenge in industrial applications.
Article
Engineering, Chemical
Ran Li, Wenzheng Xiu, Baolin Liu, Gang Zheng, Hui Yang
Summary: Research on the flow of rice particles has shown that it differs from classical spherical particles, often exhibiting multiple velocity peaks. Lowering the rotation speed of the drum can change the flow into an avalanche mode, where particles slide and cover the entire rice particle bed.
Article
Chemistry, Analytical
Xijian Lin, Yan He
Summary: This study investigates the effect of active urease system on the environment using high-speed dark-field imaging. The results show that the catalytic reaction has minimal impact on the physicochemical properties of the environment but can lead to the inhomogeneous distribution of enzymes in free solution.
ANALYTICAL CHEMISTRY
(2022)
Article
Geochemistry & Geophysics
Jianjun Liu, Zixing Xue, Zhenhai Dong, Xiaofeng Yang, Yafeng Fu, Xiaofei Man, Dongfang Lu
Summary: The study established a simulation model of Aerodynamic Drum Magnetic Separator, which can accurately control the separation effect of magnetic particles. By calculating the trajectory and capture probability of particles in different magnetic and flow fields, as well as optimizing the arrangement of magnetic poles, the enhancement effect of magnetic separator was compared.
Article
Mathematics, Interdisciplinary Applications
Suellen M. Nascimento, Rondinelli M. Lima, Rodolfo J. Brandao, Dyrney A. Santos, Claudio R. Duarte, Marcos A. S. Barrozo
Summary: This study simulated particle dynamics in a flighted rotary drum using both CFD and DEM approaches, comparing simulated solid holdups with experimental data. The research highlighted the importance of choosing an appropriate numerical approach for accurate prediction of particle dynamics in such systems.
COMPUTATIONAL PARTICLE MECHANICS
(2022)
Article
Engineering, Electrical & Electronic
Zhenzhen Liu, Yan Liu, Hongfu Zuo, Han Wang, Zhixiong Chen
Summary: This paper innovatively proposes an inline monitoring method for wear particles based on the different motion characteristics of the particles. By studying the velocity characteristics of different particles through theoretical calculations, numerical simulations, and experimental analysis, an inline optical sensor was designed and developed. The results showed that the inline sensor has excellent suitability for monitoring wear particles. This study is significant for the safe operation of large rotating machinery.
Article
Engineering, Chemical
Tim M. J. Nijssen, Mark A. H. van Dijk, Hans A. M. Kuipers, Jan van der Stel, Allert T. Adema, Kay A. Buist
Summary: Magnetic particle tracking (MPT) was used to study a rotating drum filled with cork particles in both air and water. The presence of water significantly affected the behavior of the bed, particularly the particle-wall and particle-particle interactions. The liquid-particle interaction also played a determining role in the behavior of the flowing layer. This study provides an excellent validation case for multiphase flow models.
Article
Engineering, Electrical & Electronic
Zhe Wang, Lipeng He, Zheng Zhang, Ziming Zhou, Jianwen Zhou, Guangming Cheng
Summary: This paper presents a piezoelectric energy harvester with rotational magnetic excitation, which efficiently captures energy using two driving magnets, a 5-g tip magnetic mass, and an 8-mm radial excitation distance. The results show the device produces three resonance frequencies and achieves maximum average power for primary and auxiliary piezoelectric beams.
JOURNAL OF ELECTRONIC MATERIALS
(2021)
Article
Mechanics
Mingrui Dong, Zhongzheng Wang, Benjy Marks, Yu Chen, Yixiang Gan
Summary: This study investigates partially saturated granular flows in rotating drums through experiments and simulations. It explores the effects of cohesion and rotation rate on the flow patterns and flow depth. Additionally, the study reveals that stronger cohesion promotes the formation of larger clusters.
Article
Physics, Applied
Junwu Kan, Yaqi Wu, Yiqun Gu, Shuyun Wang, Fanxu Meng, Zhonghua Zhang
Summary: This Letter proposes an indirectly excited approach to develop a drum-like piezoelectric rotational energy harvester by introducing an air-filled separation chamber. The harvester demonstrates high reliability and resonance frequency tunability, and shows potential as a sustainable power source.
APPLIED PHYSICS LETTERS
(2023)
Article
Engineering, Chemical
Hongyu Chen, Milind A. Jog, Douglas E. Evans, Leonid A. Turkevich
Summary: Dustiness evaluation is crucial in estimating potential exposure to toxic, hazardous, or irritant powders. The Rotating Drum is a widely used instrument for assessing powder dustiness, but its aerodynamics during operation is not fully understood. Utilizing computational fluid dynamics to study the flow inside the Rotating Drum can aid in interpreting dustiness measurements and guiding manufacturing processes to generate less dust.
Article
Engineering, Mechanical
Yifei Yang, Yifan Lu, Rongru Zhang, Honghao Yue
Summary: This study developed a novel, compact and integrated rotating joint with variable stiffness, capable of real-time control of rotational stiffness and motion. By changing the arm length of cantilever leaf springs, a stiffness-adjusting module with superior mechanical properties was proposed. A universal mechanical model of stiffness that adapts to a wide range of deformation was also presented. The stiffness of the joint was adjusted by reverse calculation of the motor's rotating angle, and a nonlinear Proportion-Integral-Derivative method based on a Genetic Algorithm was proposed for motion control. Experimental results demonstrated that the proposed joint has a large bearing capacity and a wide range of stiffness adjustment, and can achieve good motion control performance.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Engineering, Chemical
Meng Li, Xizhong An
Summary: This study conducted a systematic numerical investigation on the mixing characteristics and flow behaviors of Platonic solids (tetrahedra, cubes, octahedra, dodecahedra, icosahedra) in a rotating drum using the discrete element method. The research found that the rotation speed and shape of the Platonic solids have significant effects on the mixing characteristics, macroscopic properties, and microscopic properties. The mixing rate decreases and then increases with the increase of the face number of Platonic solids, and the average packing density is higher for Platonic solids with larger sphericity. The interlocking effect of cubes is not obvious, resulting in freer movement and stronger diffusive mixing in the drum.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Engineering, Chemical
W. Wu, K. Chen, E. Tsotsas
Summary: A new concept for predicting the mixing time of a large particle system based on the mixing time of a small particle system and a scale-spanning cross-correlation is proposed in this paper. The method is demonstrated using a 3D rotary drum as the large system and a 2D rotary drum as the small system. The cross-correlation, developed from a learning set, shows excellent prediction results within the parametric range of the learning set. The cross-correlation method exhibits advantages in interpretability, expandability, and relatively high accuracy compared to machine learning approaches.
ADVANCED POWDER TECHNOLOGY
(2022)
Article
Engineering, Environmental
Yehonatan David Pour, Boris Krasovitov, Andrew Fominykh, Ziba Hashemloo, Abdolreza Kharaghani, Evangelos Tsotsas, Avi Levy
Summary: In this study, a comprehensive model was developed to investigate the drying process of a single slurry droplet in a multicomponent gaseous mixture. The presence of a soluble gas was shown to increase the evaporation rate. The model was validated with experimental data and can serve as a basis for alternative drying technologies.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Chemical
Daniel Pramudita, Sowat Humjaa, Evangelos Tsotsas
Summary: Pulse combustion drying is an advanced drying technique that utilizes pulsating gas flow to reduce drying time and energy consumption while improving product quality. This study numerically investigates the denaturation of whey protein isolate during drying in pulsated gas flow and finds that small droplets undergo faster drying and denaturation, and that gas pulsation enhances drying with minimal reduction in product activity. It also shows that drying slowly at moderate temperatures is preferable to prevent excessive denaturation, and employing pulsation is a better strategy than increasing temperature to enhance the drying process while preserving product quality.
JOURNAL OF FOOD ENGINEERING
(2022)
Article
Pharmacology & Pharmacy
Maximilian Thomik, Sebastian Gruber, Anders Kaestner, Petra Foerst, Evangelos Tsotsas, Nicole Vorhauer-Huget
Summary: Experimental investigation of freeze-drying frozen maltodextrin solutions with different solid contents revealed the influence of porous structure on drying kinetics, with in situ neutron imaging showing the shape of the sublimation front during the process.
Article
Engineering, Chemical
Jialin Men, Subash Reddy Kolan, Ali Massomi, Torsten Hoffmann, Nat Jochen Schmidt, Evangelos Tsotsas, Andreas Bueck
Summary: This study presents the formulation of nanostructured heteroaggregates using the principle of fluidization and demonstrates the feasibility of two technologies, spouted bed and opposed jet fluidized bed. Intraaggregate mixing of constituents is evaluated using SEM-EDX.
CHEMIE INGENIEUR TECHNIK
(2023)
Article
Engineering, Chemical
Yehonatan David Pour, Boris Krasovitov, Andrew Fominykh, Ziba Hashemloo, Abdolreza Kharaghani, Evangelos Tsotsas, Avi Levy
Summary: This study developed a model to investigate the convective heat and mass transfer of an acoustically levitated slurry droplet that evaporates in an atmosphere containing air, water vapor, and soluble gas. The model considered various factors such as acoustic streaming, forced convection, and non-isothermal gas absorption. The results showed that the formation time of a porous shell decreased with increasing sound pressure level (SPL) and increased with increasing frequency.
Article
Thermodynamics
Simson Julian Rodrigues, Nicole Vorhauer-Huget, Evangelos Tsotsas
Summary: This study addresses the parameterization issue of the Zehner-Bauer-Schlunder model for packed beds and provides data on the effective thermal conductivity of packed beds of cubical particles. The study investigates the effects of interparticle contact area and particle conductivity on the effective thermal conductivity of the bed under different particle-to-gas thermal conductivity ratios.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Thermodynamics
Faeez Ahmad, Marc Prat, Evangelos Tsotsas, Abdolreza Kharaghani
Summary: In this study, a two-equation non-local equilibrium continuum model of isothermal drying is evaluated by comparing it with pore network simulations. The results show that the continuum model can accurately capture the non-local equilibrium effect as well as the phase distributions and drying kinetics.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2022)
Article
Chemistry, Physical
Supriya Bhaskaran, Divyansh Pandey, Vikranth Kumar Surasani, Evangelos Tsotsas, Tanja Vidakovic-Koch, Nicole Vorhauer-Huget
Summary: Based on the Shan-Chen Lattice Boltzmann Model, the invasion of oxygen in the graded porous transport layer of titanium felt is investigated. The computation domain is obtained from X-ray computed tomography. The results show that gas fingering is a common transport mechanism, and it is strongly influenced by the spatial porosity and pore size distributions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Engineering, Chemical
Serap Akbas, Kaicheng Chen, Torsten Hoffmann, Franziska Scheffler, Evangelos Tsotsas
Summary: In this study, an aerosol fluidized bed was used to coat particles with sodium benzoate solution droplets. The coverage of the coated particles was evaluated using scanning electron microscope pictures analyzed by MATLAB image processing. Monte Carlo simulation was employed to describe the coating process. The preferential deposition of droplets on already occupied positions was identified as the main reason for island growth on particles.
Article
Engineering, Chemical
Simson Julian Rodrigues, Nicole Vorhauer-Huget, Thomas Richter, Evangelos Tsotsas
Summary: Tortuosity, an important factor in packed beds or porous media, affects mass transport, thermal and electric conductivity. Current tortuosity models lack consideration for various particle shapes. This study proposes a new model that predicts tortuosity based on sphericity and porosity, demonstrating significant effects on thermal conductivity in different particle shapes. The new model shows superior performance in the porosity range of 0.3 to 0.4, making it an upgrade to the classical Zehner-Bauer-Schlunder (ZBS) model.
Article
Pharmacology & Pharmacy
Maximilian Thomik, Felix Faber, Sebastian Gruber, Petra Foerst, Evangelos Tsotsas, Nicole Vorhauer-Huget
Summary: This study presents a non-isothermal pore network model with quasi-steady vapor transport and transient heat transfer for primary freeze drying. The physically based model allows for the investigation of correlations between spatially distributed structure and transport conditions. The study focuses on regular pore network lattices with homogeneous and bimodal pore size distributions.
Article
Mechanics
Dasika Prabhat Sourya, Debashis Panda, Abdolreza Kharaghani, Evangelos Tsotsas, Pardha S. Gurugubelli, Vikranth Kumar Surasani
Summary: This study employs the Shan-Chen lattice Boltzmann method (LBM) to simulate the drying process of a capillary porous medium, investigating the effects of convection-diffusion conditions on drying kinetics and comparing them with purely diffusion-dominated kinetics. Additionally, the study explores the influence of a temperature gradient on the stability and instability of the drying front, extending the capabilities of the lattice Boltzmann method for simulating convection-diffusion drying.
Article
Mathematics, Interdisciplinary Applications
Rui Wang, Abhinandan Kumar Singh, Subash Reddy Kolan, Evangelos Tsotsas
Summary: This study generated a series of three-dimensional aggregates with different parameters using a tunable aggregation model. The fractal dimension of the aggregates was calculated using both the box-counting method and the power law method. The importance of the box-counting prefactor was highlighted, and correlations between the box-counting and power law methods were established.
FRACTAL AND FRACTIONAL
(2022)
Article
Engineering, Chemical
Tamara Milicic, Haashir Altaf, Nicole Vorhauer-Huget, Luka A. Zivkovic, Evangelos Tsotsas, Tanja Vidakovic-Koch
Summary: Proton exchange membrane water electrolyzers (PEMWEs) coupled with renewable energy resources play a crucial role in producing green hydrogen. However, these systems often suffer from significant voltage losses due to mass transport resistance. The main cause of these losses is considered to be the two-phase transport through the anode porous transport layer (PTL) and catalyst layer. A mathematical model was developed to study the two-phase flow and mass transport losses in PEMWEs, considering various operational factors.
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.
