Article
Chemistry, Multidisciplinary
Dae Yeon Kim, Seon Yeop Jung, Young Jin Lee, Kyung Hyun Ahn
Summary: In this study, the clogging dynamics in a single micropore were investigated by controlling the surface property of the particle and processing condition. The results showed that the type of particle interaction and the flow rate change had an impact on the deposition area and characteristics. Therefore, controlling the colloidal interaction and hydrodynamic stress can alleviate clogging issues.
Article
Chemistry, Physical
Ian Williams, Erdal C. Oguz, Hartmut Loewen, Wilson C. K. Poon, C. Patrick Royall
Summary: Colloids can be considered as big atoms and provide good models for atomic and molecular systems. Colloidal hard disks, serving as good models for 2D materials, have received relatively little attention in rheology despite being well-characterized in phase behavior. This study measures the shear rheology of quasi-hard-disk colloids in extreme confinement using a novel experimental setup and computer simulations. The results show that the rheological behavior of the confined system is similar to unconfined 2D and 3D hard particle systems, with the occurrence of dynamic yield stress and shear thinning.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Rachel S. Hendley, Isaac Torres-Diaz, Michael A. Bevan
Summary: By identifying analytical potentials for dipole-field and dipole-dipole interactions, we match experimental and simulated configurations of anisotropic epoxy colloidal particles in high frequency AC electric fields. The inverse Monte Carlo simulation algorithm helps determine optimal fits of analytical potentials to capture experimental observations. The stretched point dipole potential is found suitable at all concentrations, field amplitudes, and degrees of ordering, showing simplicity, accuracy, and adjustability for modeling field mediated microstructures and assembly of systematically varying anisotropic particle shapes.
Article
Mechanics
Emma Gonzalez, Christian Aponte-Rivera, Roseanna N. Zia
Summary: In this study, a computational investigation was conducted on the equilibrium dynamics of a polydisperse hard-sphere colloidal dispersion confined in a spherical cavity. The results showed that although polydispersity tends to homogenize structure in a suspension, strong correlations induced by the cavity resist this homogenization. The effects of polydispersity on particle dynamics were found to weaken lubrication effects near the cavity wall and drive diffusivity changes by affecting many-body hydrodynamic couplings.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Multidisciplinary Sciences
Yuliang Jin, Hajime Yoshino
Summary: The concept of jamming has attracted great research interest due to its broad relevance in soft-matter and its connection to sphere packing and optimization problems. The study shows that amorphous jammed states of frictionless spheres can be extended from a fixed density jamming-point to a jamming-plane that spans density and shear strain axes. The jamming-plane can be divided into reversible-jamming and irreversible-jamming regimes, reflecting the escape from metastable glass basins.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Chemistry, Multidisciplinary
Kristine M. Smith, Lilian C. Hsiao
Summary: The study reveals that the cluster-level structural parameters of colloidal thermogelling nanoemulsions in channel flow are influenced by attractive interactions and local shear stress. Specifically, under strong attractions, the largest clusters are affected by confinement and accumulate towards the central axis of the channel, resulting in a volume fraction gradient. Larger gel clusters formed under strong attractions and low shear stresses are susceptible to shear-induced migration, intensifying r-dependent heterogeneity and deviations in flow behavior.
Article
Physics, Fluids & Plasmas
Rijan Maharjan, Ethan O'Reilly, Thomas Postiglione, Nikita Klimenko, Eric Brown
Summary: Surface roughening events in discontinuous shear thickening suspensions are found to be intermittent and localized spatially, with dilation and stresses confirmed to be coupled in the high-stress state of DST. The surface roughening is most prominent during stress growth from low- to high-stress states. Fluctuations in shear and normal stresses were also observed between high- and low-stress states.
Article
Chemistry, Physical
Muhammad Hassan, Connor Williamson, Joshua Baptiste, Stefanie Braun, Anthony J. Stace, Elena Besley, Benjamin Stamm
Summary: This study presents a quantitative method for evaluating the electrostatic interactions between dielectric particles in an external electric field, taking into account inhomogeneous charge distributions and pointlike charges on the particle surface. The numerical results validate the proposed method and highlight the limitations of the fixed dipole approximation at small particle separations. The method is also applied to investigate the stability and melting of ionic colloidal crystals under an external electric field.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
C. K. Sarika, Sayantan Majumdar, A. K. Sood
Summary: This study investigates the flow behavior of ultra-dilute fractal suspensions and reveals a direct transition from flowing to a shear jammed state. The research uncovers the fragility and contact dynamics unique to fractal suspensions and proposes a generic phase diagram to describe this transition.
Article
Chemistry, Multidisciplinary
Lucille Chambon, Mohan Das, Evangelia Vasilaki, George Petekidis, Maria Vamvakaki
Summary: Temperature-sensitive rod-like colloidal particles were synthesized by grafting a temperature-responsive polymer on the surface of silica rods. The stability of the grafted polymer decreased with time in aqueous solutions, but can be suppressed by growing a hydrophobic polymer block on the particle surface. The rod-like particles exhibited temperature-responsive behavior but showed irreversible aggregation upon increasing the temperature.
Article
Chemistry, Physical
J. Alejandro Rivera-Moran, Yi Liu, Samuel Monter, Chiao-Peng Hsu, Pia Ruckdeschel, Markus Retsch, Maciej Lisicki, Peter R. Lang
Summary: The near-wall Brownian dynamics of different types of colloidal particles were investigated, revealing that rough particles diffuse significantly slower compared to smooth particles. This difference in dynamics is attributed to the rough particles significantly changing their DLVO interaction with the wall, affecting their diffusion.
Article
Acoustics
C. Q. Ru
Summary: A simple model is proposed to study wave propagation in hard sphere-reinforced elastic random composites. The model offers a potential method to study various three-dimensional dynamic problems and shows reasonably good agreement with established known data.
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
(2022)
Article
Physics, Multidisciplinary
Jiaxing Yuan, Kyohei Takae, Hajime Tanaka
Summary: In this study, the role of hydrodynamic interactions (HIs) in the self-assembly of oppositely charged colloidal particles was investigated. It was found that under a constant electric field, HIs lead to the formation of clusters and percolation into a gel network, unlike previous simulations that neglected HIs.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Taiki Hoshino, Masanari Nakayama, Yoshihiro Hosokawa, Kohei Mochizuki, Satoshi Kajiyama, Yoshiki Kohmura, Takashi Kato
Summary: Self-organized supramolecular assemblies are commonly found in nature and technology, and their reversible non-covalent bonding allows for dynamic functions such as stimuli-responsive switching and self-healing. However, the specific dynamics of these assemblies remain unclear due to the diverse molecular motions generated by multiple intermolecular interactions.
NANOSCALE ADVANCES
(2023)
Article
Chemistry, Multidisciplinary
Kohji Ohno, Tatsuya Hisatomi, Haruna Seo
Summary: Colloidal crystals are self-assembled systems suitable for studying crystallization. By synthesizing charged-polymer-brush-decorated core-shell hybrid particles through surface-initiated living radical polymerization, colloidal crystals were successfully constructed in an organic solvent.
Article
Chemistry, Applied
Mairi Brown, Francesca Laitano, Calum Williams, Bruce Gibson, Mark Haw, Jan Sefcik, Karen Johnston
FOOD HYDROCOLLOIDS
(2019)
Article
Mechanics
Oguzhan Der, Volfango Bertola
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2020)
Article
Mechanics
Eliane Younes, Michal Himl, Zdenek Stary, Volfango Bertola, Teodor Burghelea
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2020)
Article
Engineering, Mechanical
Sako Azeez, Volfango Bertola
Summary: The lubrication of hydrodynamic journal bearings using shear thinning fluids was investigated by comparing three different constitutive models. The Carreau and Cross models yield higher magnitudes of pressure at high shear rates compared to the power-law model, but all three models are in better agreement at low shear rates.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART J-JOURNAL OF ENGINEERING TRIBOLOGY
(2021)
Article
Physics, Fluids & Plasmas
Eliane Younes, Volfango Bertola, Cathy Castelain, Teodor Burghelea
PHYSICAL REVIEW FLUIDS
(2020)
Article
Thermodynamics
Oguzhan Der, Ali Ahmed Alqahtani, Marco Marengo, Volfango Bertola
Summary: The thermal performance of flat polypropylene pulsating heat pipes was analyzed through experiments with different design parameters, providing insights for future applications in thermal management of electronics and satellites.
APPLIED THERMAL ENGINEERING
(2021)
Article
Engineering, Environmental
Hesam Maleki, Matt Fulton, Volfango Bertola
Summary: A flat-plate microreactor was designed for on-board hydrogen generation through ammonia decomposition using CoCeAlO catalyst, with catalyst synthesis and immobilization assisted by inkjet printing technology. Kinetic experiments were conducted to analyze the impact of reaction temperature and NH3 flow rate, resulting in the development of two kinetic rate expressions and successful implementation in a CFD model. The simulation demonstrated high accuracy in predicting flow properties, with the microreactor operating under kinetic-control conditions and offering ease of component assembly and catalyst probing.
CHEMICAL ENGINEERING JOURNAL
(2021)
Review
Chemistry, Physical
Ali Ahmed Alqahtani, Volfango Bertola
Summary: This article critically reviews the application of polymeric and composite materials in two-phase passive heat transfer devices, focusing on the advantages and disadvantages of these materials in thermal management systems. Recent technological developments have led to an increase in power density in various applications, such as portable electronics and space systems, necessitating high-performance and compact thermal management systems. Passive two-phase systems are considered the most promising heat transfer devices for dissipating large heat fluxes without the need for external power supply. Traditionally, heat transfer systems have been constructed using metals due to their excellent thermal properties. However, there is growing interest in replacing metallic materials with polymers and composites, which can offer cost-effectiveness, light weight, and high mechanical flexibility. This review discusses the state-of-the-art applications of polymers and composites in two-phase passive thermal management systems, along with an analysis of their limitations and technical challenges.
Article
Chemistry, Multidisciplinary
Andrew Cashmore, Russell Miller, Hikaru Jolliffe, Cameron J. Brown, Mei Lee, Mark D. Haw, Jan Sefcik
Summary: This article presents an experimental workflow for the rapid assessment of primary and secondary nucleation and crystal growth kinetics under supersaturation conditions. By conducting experiments, researchers can quantify and analyze the effects of supersaturation on the nucleation and growth kinetics of α-glycine in aqueous solutions at isothermal conditions. This approach provides a means to estimate the absolute values of nucleation and growth rates and gain insights into crystallization behavior, which can be used to optimize batch or continuous crystallization processes.
CRYSTAL GROWTH & DESIGN
(2023)
Article
Crystallography
James M. Flannigan, Daniel Maciver, Hikaru Jolliffe, Mark D. Haw, Jan Sefcik
Summary: Despite the widespread occurrence of sodium chloride crystallization, there have been few detailed studies on its kinetics. This study examines the nucleation kinetics of sodium chloride crystallization using advanced technology and demonstrates the significant effect of crystallization conditions. The study also evaluates the workflow and models used for data interpretation, comparing them with other crystal systems.
Article
Chemistry, Physical
Volfango Bertola
Summary: The micro-scale morphology of the receding contact line of dilute polyethylene oxide solution drops on a fluorinated hydrophobic surface is investigated. Transient liquid filaments and dendritic structures are observed, which evolve into a bead-on-a-string structure similar to the capillary breakup mechanism of dilute polymer solutions. The quantitative estimation of the average polymer force per unit contact line length explains the reduction of the contact line retraction velocity observed experimentally.
COLLOIDS AND INTERFACES
(2022)
Article
Engineering, Mechanical
D. Biole, V Bertola
Summary: Modern high-speed digital cameras provide unprecedented resolution for studying fluid flows in both space and time. This includes the investigation of drop impact and dynamic wetting phenomena, which exhibit unique features such as contact angles and occur on millisecond time scales.
JOURNAL OF FLOW VISUALIZATION AND IMAGE PROCESSING
(2021)
Review
Chemistry, Physical
Hesam Maleki, Volfango Bertola
CATALYSIS SCIENCE & TECHNOLOGY
(2020)
Article
Nanoscience & Nanotechnology
Hesam Maleki, Volfango Bertola
ACS APPLIED NANO MATERIALS
(2019)
Article
Physics, Fluids & Plasmas
Mark D. Haw
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.