Article
Physics, Fluids & Plasmas
Thanh-Trung Vo, Trung-Kien Nguyen
Summary: Using three-dimensional discrete element method simulations, a power-law fitting form is introduced to describe the final penetration depth of a spherical intruder with low velocity vertically penetrating into dry and wet granular packings, providing physical insights into the material properties of granular packings and the impact conditions on the final penetration depth.
Article
Chemistry, Physical
Manuel Cardenas-Barrantes, David Cantor, Jonathan Bares, Mathieu Renouf, Emilien Azema
Summary: This study analyzes the compaction behavior of assemblies composed of soft spherical particles using three-dimensional non-smooth contact dynamic simulations. The evolution of packing fraction, coordination number, and von Misses stress distribution within the particles with increasing confining stress is characterized. A transition is observed from granular-like material to continuous-like material as the confining stress increases. An equation describing the evolution of packing fraction as a function of applied pressure is developed, providing accurate predictions up to very high densities without parameter tuning.
Article
Physics, Multidisciplinary
Kuang Liu, Jonathan E. Kollmer, Karen E. Daniels, J. M. Schwarz, Silke Henkes
Summary: In experiments on sheared two-dimensional frictional granular materials, rigidity emerges as a rigid backbone interspersed with floppy, particle-filled holes, creating a spongelike morphology. This rigid structure, identified at a critical contact number, exhibits higher pressure within than outside, suggesting the importance of focusing on mechanical stability arising through arch structures and hinges at the mesoscale.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Olivier Pitois, Ali Salame, Yacine Khidas, Margaux Ceccaldi, Vincent Langlois, Sebastien Vincent-Bonnieu
Summary: This study investigates the distribution of liquid in foam-filled granular media under pore confinement. The findings reveal a pendular-like regime in the foam-filled granular assemblies, with daisy-shaped liquid bridges between the grains. A theoretical model is proposed to describe the foam liquid bridges, which can potentially be used to bind granular assemblies and transform them into solid materials.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Physics, Multidisciplinary
Ye Yuan, Yi Xing, Jie Zheng, Zhifeng Li, Houfei Yuan, Shuyang Mang, Zhikun Zeng, Chengjie Xia, Hua Tong, Walter Kob, Jie Zhang, Yujie Wang
Summary: By using X-ray tomography, this study investigates granular packings with different friction coefficients under mechanical tapping, validating the Edwards volume ensemble and establishing a granular version of the zeroth law of thermodynamics. The research explicitly clarifies how friction influences granular statistical mechanics and determines the entropy as a function of packing fraction and friction. Furthermore, a granular jamming phase diagram is obtained based on geometric coordination number and packing fraction.
PHYSICAL REVIEW LETTERS
(2021)
Article
Thermodynamics
Shuo Shi, Kaijun Jiang, Sheng Chen, Zijian Zhou, Xiaoze Du
Summary: This study investigates the shear-induced anisotropy of the effective thermal conductivity (ETC) in granular packings during quasistatic shear deformation. The discrete element method is utilized to track the position, force, and contact condition of each particle in the packing. The ETC of the packing at different shear strains is evaluated using the particle-resolved finite element method. The findings demonstrate that the anisotropy ratio of the ETC can reach 40% when the shear strain increases to 0.11, primarily due to the variation in the contact network formed during consecutive shear steps. Contacts with large contact radius and strong thermal conductance are shown to align preferentially with the direction of deformation, influencing the anisotropy of thermal conductivity. Grouping contacts into sub-networks based on contact strength reveals that the thermal conductivity anisotropy of a packing is predominantly caused by strong contacts.
APPLIED THERMAL ENGINEERING
(2023)
Article
Physics, Multidisciplinary
Zackery A. Benson, Anton Peshkov, Nicole Yunger Halpern, Derek C. Richardson, Wolfgang Losert
Summary: The study investigates the reversibility of a three-dimensional granular system under cyclic compression and reveals the significant role of rotational motion in granular flows. The findings indicate that 3D rotations are irreversible under cyclic compression, leading to the accumulation of dissipative contact-point sliding throughout the cycle.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
Mahnoush Madani, Maniya Maleki, Janos Torok, M. Reza Shaebani
Summary: This study investigates shear localization in a split-bottom Couette cell with smooth walls under confining pressure using both experimental and numerical approaches. It shows how the characteristics of the shear zone evolve with changes in confining pressure and wall slip, and reveals that increasing applied pressure causes the shear zone to move towards the center of the cylinder, widen, and reduce angular velocity.
Article
Physics, Fluids & Plasmas
Philip Wang, Shiyun Zhang, Philip Tuckman, Nicholas T. Ouellette, Mark D. Shattuck, Corey S. O'Hern
Summary: In the process of compression, the form of shear modulus is largely determined by affine response, with deviations from this form caused by nonaffine particle motion in near-isostatic geometrical families. Ensemble-averaged shear modulus is not simply a sum of two power laws, but exhibits a complex relationship described by specific characteristic pressures and power law exponents.
Article
Physics, Multidisciplinary
A. Plati, A. Puglisi
Summary: We conduct simulations on vertically shaken dense granular packings with horizontal periodic boundary conditions. We find that a coordinated translating motion of the whole medium emerges when the horizontal symmetry is broken by disorder or defects in the packing and the shaking is weak enough to conserve the structure. We suggest that this drift arises from the interplay between structural symmetry breaking and frictional forces transmitted by the vibrating plate. A nonlinear ratchet model with stick slips is able to replicate many aspects of this phenomenon. The collective motion discussed here underlies phenomena observed recently with vibrofluidized granular materials, such as persistent rotations and anomalous diffusion.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Fluids & Plasmas
Juan C. Petit, Nishant Kumar, Stefan Luding, Matthias Sperl
Summary: This study presents three-dimensional simulations of bidisperse granular packings using the discrete element method. The results show the existence of two jamming transitions, with the first one predominantly involving large particles and the second one involving small-large interactions. The effective transition densities are reduced when only nonrattlers are considered. The size ratio and concentration of small particles affect the behavior of the bulk modulus during the transitions. The findings provide insights for tuning or switching the bulk modulus and other properties of granular packings.
Article
Physics, Multidisciplinary
James D. Sartor, Sean A. Ridout, Eric Corwin
Summary: This letter explores the mean-field theory of jamming and its accuracy in different dimensions, showing that the predictions of mean field theory are exact in low dimensions. This suggests that the infinite dimensional limit is not necessary to obtain these results.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Mark Brown, Joel E. Cohen, Chuan-Fa Tang, Sheung Chi Phillip Yam
Summary: We generalize Taylor's law to heavy-tailed distributions with tail index alpha in (0, 1) and infinite mean, demonstrating specific relationships between sample statistics and sample mean as sample size increases. These scaling relationships characterize the risk-adjusted performance of investments and are known as Taylor's law in ecology and fluctuation scaling in physics.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Engineering, Chemical
Angga Pratama Herman, Zongyan Zhou, Jieqing Gan, Aibing Yu
Summary: This study investigates the mixing of granular materials in rotating drums with different volumes. The results show that mixing performance is affected by drum size and particle diameter. A correlation equation is proposed for predicting mixing rate, and the ratio of drum diameter to particle diameter influences particle travel distances and displacements. The findings are significant for understanding the mixing mechanism of granular materials.
Article
Chemistry, Physical
Matthew Macaulay, Pierre Rognon
Summary: In this study, discrete element simulations were used to measure the viscosity of cohesive granular materials, identifying two key dimensionless numbers that control viscosity. The research reveals a relationship between variations in viscosity and changes in flow microstructure and contact network induced by adhesion.
Correction
Polymer Science
Xiaohui Xu, Navid Bizmark, Kofi S. S. Christie, Sujit S. Datta, Zhiyong Jason Ren, Rodney D. Priestley
Article
Polymer Science
Xiaohui Xu, Navid Bizmark, Kofi S. S. Christie, Sujit S. Datta, Zhiyong Jason Ren, Rodney D. Priestley
Summary: To address the scarcity of fresh water, new technologies are needed to produce potable water from various sources. Thermoresponsive polymers, with their low-energy production and biocompatibility, offer sustainable routes for fresh water generation. This Perspective summarizes the design and application of poly(N-isopropylacrylamide)-based thermoresponsive microgels and hydrogels, showcasing their potential for water purification.
Article
Physics, Multidisciplinary
Ricard Alert, Alejandro Martinez-Calvo, Sujit S. Datta
Summary: This article theoretically demonstrates the limitations in stability of chemotactic fronts to morphological perturbations caused by the ability of individual cells to sense and respond to chemical gradients. The competition between cells at bulging parts of a front, where they are exposed to a smaller gradient but respond more strongly to it, determines whether the front is stable or not. The study suggests that the sensory machinery of cells might have evolved to avoid these limitations and ensure stable front propagation, and this principle may also apply to other types of directed migration.
PHYSICAL REVIEW LETTERS
(2022)
Article
Biochemical Research Methods
Daniel B. Amchin, Jenna A. Ott, Tapomoy Bhattacharjee, Sujit S. Datta
Summary: This article examines the impact of confinement on the dynamics of bacterial spreading by extending the Keller-Segel model to incorporate cellular growth, division, and confinement. Numerical simulations demonstrate how confinement fundamentally alters the dynamics and morphology of spreading bacterial populations, leading to a transition from chemotactic spreading to growth-driven spreading.
PLOS COMPUTATIONAL BIOLOGY
(2022)
Article
Mechanics
Christopher A. Browne, Richard B. Huang, Callie W. Zheng, Sujit S. Datta
Summary: Many processes in environmental, industrial, and energy fields rely on controlling fluid transport in subsurface porous media. Using direct visualization, we show that polymer additives can homogenize flow by inducing elastic flow instability, resulting in random fluctuations and excess flow resistance in individual strata. This instability occurs at lower flow rates in higher-permeability strata, diverting flow towards lower-permeability strata and promoting flow homogenization. Based on the experiments, we develop a model that quantitatively predicts the optimal flow rate for homogenization in a given stratified medium. Our work offers a new approach to homogenizing fluid and passive scalar transport in heterogeneous porous media.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Physics, Multidisciplinary
Gess Kelly, Navid Bizmark, Bulbul Chakraborty, Sujit S. Datt, Thomas G. Fai
Summary: This study explores the deposition of particles flowing in a microfluidic network under the influence of fluid dynamics, specifically the pressure gradient and wall shear stress in a channel. Experimental observations show that particles deposit locally at the inlet at lower pressure drop, while they deposit uniformly along the direction of flow at higher pressure drop. A mathematical model and agent-based simulations are developed to capture and explain these qualitative features. The deposition profile is explored over a two-dimensional phase diagram defined by the pressure and shear stress threshold, revealing the existence of two distinct phases.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Xiaohui Xu, Nehemie Guillomaitre, Kofi S. S. Christie, R. Konane Bay, Navid Bizmark, Sujit S. Datta, Zhiyong Jason Ren, Rodney D. Priestley
Summary: Hydrogels show great promise in energy and environmental applications, particularly in water purification and harvesting. The main challenge is the low water production rate, which fails to meet daily human demand. To address this issue, a rapid-response, antifouling solar absorber gel (LSAG) was developed, capable of producing potable water from contaminated sources at a rate sufficient to meet daily water demand. The LSAG integrates various materials to enhance photothermal response and prevent fouling, while its unique structure enables enhanced water transport. It can also purify water from harmful sources, including those containing small molecules, oils, metals, and microplastics.
ACS CENTRAL SCIENCE
(2023)
Article
Physics, Multidisciplinary
Hongbo Zhao, Andrej Kosmrlj, Sujit S. Datta
Summary: Research shows that there is a strong competition between collective chemotaxis and motility-induced phase separation (MIPS). Collective chemotaxis can suppress or inhibit phase separation, and it can also generate new dynamic instabilities. These findings contribute to the understanding and clarification of the rich physics underlying active matter systems, ranging from cells to robots.
PHYSICAL REVIEW LETTERS
(2023)
Article
Multidisciplinary Sciences
Jason X. Liu, Mikko P. Haataja, Andrej Kosmrlj, Sujit S. Datta, Craig B. Arnold, Rodney D. Priestley
Summary: This study investigated the complex interplay between phase separation, network mechanics, and condensate capillarity, providing an explanation for phenomena in complex environments like the cellular interior.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Xiaohui Xu, Yannick L. Eatmon, Kofi S. S. Christie, Allyson L. McGaughey, Nehemie Guillomaitre, Sujit S. Datta, Zhiyong Jason Ren, Craig Arnold, Rodney D. Priestley
Summary: Hydrogels can be transformed into tough and recyclable supramolecular phase-separated gels (PSGs) through a dehydration-hydration approach, which exhibit excellent mechanical performance and environmental tolerance. PSGs can be used as strain sensors in soft robotics and autonomous sensing applications.
Article
Biochemical Research Methods
Sujit S. Datta, Ilenia Battiato, Martin A. Ferno, Ruben Juanes, Shima Parsa, Valentina Prigiobbe, Enric Santanach-Carreras, Wen Song, Sibani Lisa Biswal, David Sinton
Summary: Transitioning to a sustainable future requires a transformation of energy and environmental technologies. Lab-on-a-chip (LoC) systems can contribute to this transition by studying and developing new processes and materials in areas such as carbon sequestration, hydrogen storage, geothermal energy extraction, bioenergy, critical materials recovery, and water filtration. It is important to engage the LoC community and raise awareness among researchers, industry experts, and policy makers about the potential of LoC approaches in achieving a low-carbon future.
Article
Chemistry, Physical
Chaitanya Joshi, Mathew Q. Giso, Jean-Francois Louf, Sujit S. Datta, Timothy J. Atherton
Summary: In this study, we approach the problem of hydrogel swelling under physical constraints as an energy optimization problem. By applying our method, we were able to compute the equilibrium shapes of hydrogel spheres confined within a jammed matrix of rigid beads, and interpret the results to understand how confinement affects the mechanics of swollen hydrogels. We found that confinement leads to spatial separation of strains within the bulk of the hydrogel and a transition from Hertzian to non-Hertzian behavior in contact mechanics as swelling occurs.
Article
Chemistry, Physical
Chaitanya Joshi, Mathew Q. Giso, Jean-Francois Louf, Sujit S. Datta, Timothy J. Atherton
Summary: This study presents an energy optimization approach to solve the problem of hydrogel swelling under physical constraints. The equilibrium shapes of hydrogel spheres confined within a jammed matrix of rigid beads are computed using this method, and the results provide insights into how confinement modifies the mechanics of swollen hydrogels.
Article
Physics, Multidisciplinary
Joanna Schneider, Christopher A. Browne, Malcolm Slutzky, Cecilia A. Quirk, Daniel B. Amchin, Sujit S. Datta
Summary: This study uses theory and simulation to investigate the coupled processes of drainage in porous media. The researchers identify two distinct drainage behaviors and quantitatively determine the conditions under which they occur. The findings expand the current understanding of these processes and have implications for the application of drainage in various industries and environmental contexts.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Chemistry, Physical
Navid Bizmark, Nicholas J. Caggiano, Jason X. Liu, Craig B. Arnold, Robert K. Prud'homme, Sujit S. Datta, Rodney D. Priestley
Summary: This study investigates the mechanisms and dynamics of phase transitions for cellulose ethers using experiments and theoretical considerations. The research finds that hydroxypropyl substituents favor the spontaneous formation of liquid droplets, while methyl substituents induce fibril formation through diffusive growth. In celluloses with both methyl and hydroxypropyl substituents, fibrillation initiates after liquid droplet formation.
