Article
Engineering, Multidisciplinary
Hassnia Hajji, Lioua Kolsi, Kaouther Ghachem, Chemseddine Maatki, Ahmed Kadhim Hussein, Mohamed Naceur Borjini
Summary: This study presents two and three-dimensional numerical simulations of flow through sudden expansion and contraction microchannels. Results show the appearance of a separate vortex in the corner after sudden expansion for low Reynolds numbers, with the vortex separation length increasing for high Reynolds numbers. The three-dimensional character of flow is more pronounced for higher Reynolds numbers.
ALEXANDRIA ENGINEERING JOURNAL
(2021)
Article
Mechanics
Van Thanh Hoang, Van Duong Le, Jang Min Park, Bich -Tram Truong-Le
Summary: This study investigates droplet dynamics in contraction microchannels using three-dimensional simulation and theoretical modeling. The results identify three regimes of droplet dynamics: trap, squeeze, and breakup. The effects of capillary number, entry angle, and contraction channel ratio are explored. A theoretical model is proposed to describe the transition between squeeze and trap regimes, dependent on the entry angle. The findings provide valuable recommendations for designing contraction microchannels.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2023)
Article
Thermodynamics
Hassnia Hajji, Lioua Kolsi, Faouzi Askri, Chemseddine Maatki, Walid Hassen, Mohamed Borjini
Summary: The study shows that obstacles have a significant impact on fluid dynamics and heat transfer, especially leading to the formation of a separate vortex after the sudden expansion of the micro-channel.
Article
Thermodynamics
N. S. Shashikumar, Macha Madhu, S. Sindhu, B. J. Gireesha, Naikoti Kishan
Summary: This article investigates the steady flow of Williamson fluid in a micro-channel with viscous dissipation, magnetic effect, and Joule dissipation. The results indicate that the magnetic effect enhances the Bejan number and a significant decrease in fluid temperature is observed at higher Biot numbers.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Construction & Building Technology
Jiaqi Chen, Lanchun Zhang, Yinfei Du, Hao Wang, Hancheng Dan
Summary: The paper develops a 3-D microstructure-based FE model to evaluate the CTE and CTC of asphalt concrete, generated with an image-aided algorithm. Results from laboratory experiments validate the numerical simulation, showing relative differences between average values of numerical and experimental data.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Radiology, Nuclear Medicine & Medical Imaging
Masaaki Omura, Michio Takeuchi, Ryo Nagaoka, Hideyuki Hasegawa
Summary: The study shows that the variation in ultrasonic envelope statistics is correlated with temperature changes inside scattering media. By using finite element simulations, the change in scatterer distribution during thermal expansion or contraction is numerically reproduced. Results indicate that the change in scatterer number density is related to volume change during temperature elevation, and the magnitude of the Delta m shift increases with higher thermal expansion coefficients.
Article
Physics, Multidisciplinary
N. S. Shashikumar, S. Sindhu, Macha Madhu, B. J. Gireesha
Summary: This study constructs a Carreau fluid for investigating the entropy rate of magnetohydrodynamic steady fluid flow in a micro-channel. It considers the second law of thermodynamics and rheological properties of the Carreau fluid. The research is relevant to various fields such as microchannel heat sinks, heat exchangers, microwave amplifier manufacturing, and renewable energy. Numerical simulations using the Finite Element Method reveal that the entropy and Bejan number exhibit an increasing trend with the magnetic parameter.
WAVES IN RANDOM AND COMPLEX MEDIA
(2022)
Article
Telecommunications
Shailendra Kumar Pathak, Shashi Prakash
Summary: This research focuses on adjusting the time-varying and heterogeneous traffic in Elastic Optical Networks (EONs) through spectrum expansion/contraction (SEC) policies. It proposes a Traffic Aggregation-based Routing and Spectrum Allocation (TARSA) algorithm to increase the expansion region between adjacent connections and improve network performance.
WIRELESS PERSONAL COMMUNICATIONS
(2021)
Article
Engineering, Mechanical
Chang-Kyun Lee, Eun-ho Lee, Jinwoo Im, ChiWoong Ra, No-Cheol Park
Summary: In this study, an elasto-plastic analysis using a beam element-based model was investigated to evaluate the strain response of piping systems under seismic conditions. The appropriate level of flexibility and Fourier expansion number was determined to ensure accuracy and conservatism. The results showed that using the flexibility factor and Fourier expansion number is effective in accurately predicting strain response in nuclear power plant piping systems.
JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY
(2022)
Article
Engineering, Mechanical
N. S. Shashikumar, K. Thriveni, Macha Madhu, B. Mahanthesh, B. J. Gireesha, N. Kishan
Summary: The study focuses on investigating flow and heat transport characteristics of non-Newtonian Williamson fluid in an inclined micro-channel, along with entropy generation analysis. The significance of thermal radiation, convective boundary condition, and multiple slip effects is explored. Numerical results show an escalating trend in entropy generation and Bejan number with increasing angle of inclination, with the Bejan number behavior changing at two points for different Reynolds' numbers.
PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART E-JOURNAL OF PROCESS MECHANICAL ENGINEERING
(2021)
Article
Materials Science, Multidisciplinary
Minshui Huang, Zihao Wan, Yongzhi Lei, Xin Shi, Guoming Shu
Summary: This paper proposes a new type of steel-PVA hybrid fiber concrete for use in the anchorage zone of a bridge expansion and contraction installation, with high early strength and better road performance. Through experiments and finite element modeling, it is confirmed that the improved concrete has better road performance and practical value in construction.
MATERIALI IN TEHNOLOGIJE
(2021)
Article
Computer Science, Information Systems
Jean Claude Bajard, Kazuhide Fukushima, Thomas Plantard, Arnaud Sipasseuth
Summary: Residue Number Systems (RNS) have been proven effective in speeding up computations involving additions and products, particularly in the field of cryptographic engineering. This article presents four techniques to extract RNS bases from specific sets of integers, improving performance and flexibility.
IEEE TRANSACTIONS ON EMERGING TOPICS IN COMPUTING
(2022)
Article
Energy & Fuels
Macha Madhu, N. S. Shashikumar, B. J. Gireesha, Naikoti Kishan
Summary: This study investigates the impact of entropy generation in Eyring-Powell fluid flow through a microchannel with thermal/exponential heat source coefficients using the Finite Element Method. Through the analysis, it is found that thermal performance can be enhanced by controlling parameters such as magnetic field, viscous heating, Joule heating, and convective condition. Additionally, it is observed that entropy generation increases with higher Grashof numbers.
INTERNATIONAL JOURNAL OF AMBIENT ENERGY
(2021)
Article
Computer Science, Hardware & Architecture
Yang Su, Bai-Long Yang, Chen Yang, Ze-Peng Yang, Yi-Wei Liu
Summary: In this article, an area-efficient and highly unified reconfigurable multicore NTT/INTT architecture is proposed for polynomial multiplication in RLWE-based FHE schemes. The architecture achieves significant improvements in throughput and area efficiency compared to prior works.
IEEE TRANSACTIONS ON VERY LARGE SCALE INTEGRATION (VLSI) SYSTEMS
(2022)
Proceedings Paper
Computer Science, Artificial Intelligence
Kristina Tandukar, Razwan Mohmed Salah, Nada AlSallami, Syed Altaf, Shahad Ahmed, Guninder Sandhu
Summary: This study introduces a new taxonomy called DTR, which focuses on the components of data, transverse image processing, and response to processed outcome for implementing computer aided simulation in 3D maxillary surgery. The DTR taxonomy is validated and evaluated based on accuracy, stress distribution, and stress displacement, and nine state-of-the-art research papers in the domain of 3D-CAS expansion in maxillary surgery systems are classified. The findings demonstrate the effectiveness of the DTR taxonomy and the validated components in maxillary surgery expansion.
PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON INNOVATIONS IN COMPUTING RESEARCH (ICR'22)
(2022)
Article
Mechanics
Sami Yamani, Gareth H. McKinley
Summary: The FENE-P dumbbell constitutive equation is commonly used for simulating viscoelastic shear flows and predicting macroscopic properties of dilute polymer solutions. By evaluating steady material functions, universal master curves for these functions, as well as the corresponding stress ratio, can be constructed, which helps in understanding the effects of finite extensibility of polymer chains.
JOURNAL OF NON-NEWTONIAN FLUID MECHANICS
(2023)
Article
Mechanics
Joshua David John Rathinaraj, Gareth H. McKinley
Summary: Oscillatory rheometric techniques are widely used to characterize the viscoelastic properties of complex fluids. However, conventional Fourier transforms for analyzing oscillatory data are limited in studying shear-induced microstructural changes in time-evolving materials. In this study, the Gabor transform is explored as a more advanced signal processing technique to extract time-resolved frequency information from oscillatory data. The Gabor transform enables accurate measurement of rapid changes in storage and loss modulus, extraction of characteristic thixotropic/aging time scale, and extraction of useful viscoelastic data from initial transient response. The resulting test protocol, Gaborheometry, reduces the number of required experiments and data postprocessing time significantly.
JOURNAL OF RHEOLOGY
(2023)
Article
Mechanics
Esteban F. Medina-Banuelos, Benjamin M. Marin-Santibanez, Emad Chaparian, Crystal E. Owens, Gareth H. McKinley, Jose Perez-Gonzalez
Summary: It has been discovered that the steady fractal vane-in-cup (fVIC) flow of complex fluids using vanes with fractal cross sections can produce an almost axisymmetric flow field and rotation rate-independent effective radius, making it a reliable measurement tool for complex fluids. However, axial shearing/compression during the insertion of the rheometric tool in the sample also accelerates syneresis, leading to shear banding for Couette and fVIC flows.
JOURNAL OF RHEOLOGY
(2023)
Article
Polymer Science
Gauthier Legrand, Sebastien Manneville, Gareth H. McKinley, Thibaut Divoux
Summary: Nanocomposite gels formed by mixing hydrophobic colloidal soot particles and a sodium salt of carboxymethylcellulose (CMC), known as cellulose gum, exhibit different mechanical behaviors depending on the relative content of the two components. At low CMC concentration, the gel shows electric conductivity and glassy-like viscoelastic behavior, while at higher CMC concentration, the gel becomes nonconductive and displays power-law viscoelastic behavior. The CMC plays a crucial role in the gel's viscoelastic properties. These findings provide valuable insights for designing nanocomposite gels based on hydrophobic interactions.
Article
Physics, Multidisciplinary
Minaspi Bantawa, Bavand Keshavarz, Michela Geri, Mehdi Bouzid, Thibaut Divoux, Gareth H. McKinley, Emanuela Del Gado
Summary: Soft particulate gels consist of a small amount of particulate matter dispersed in a continuous fluid phase. The mechanical response and gel elasticity are determined by the particle volume fraction. However, the diverse range of functional dependencies reported experimentally has made it difficult to identify general scaling laws.
Article
Mechanics
Jelle J. J. Schoppink, Keerthana Mohan, Miguel A. A. Quetzeri-Santiago, Gareth McKinley, David Fernandez Rivas, Andrew K. K. Dickerson
Summary: By selectively coating hydrophobic strips on hydrophilic glass capillaries, the trajectory and characteristics of the microjet can be influenced and controlled.
Article
Materials Science, Biomaterials
Mario Milazzo, Vincent Fitzpatrick, Crystal E. Owens, Igor M. Carraretto, Gareth H. McKinley, David L. Kaplan, Markus J. Buehler
Summary: This study investigates the rheology, printability, and prosthetic mechanical properties of HA and HA-silk protein composites, highlighting the roles of composition and water content. The inclusion of silk improves the quality of printed items by reducing underextrusion and slumping. A printing map is constructed to guide the manufacturing of HA-based inks for biomedical applications requiring sub-millimetric features.
ACS BIOMATERIALS SCIENCE & ENGINEERING
(2023)
Article
Physics, Fluids & Plasmas
Sami Yamani, Yashasvi Raj, Tamer A. Zaki, Gareth H. McKinley, Irmgard Bischofberger
Summary: The interplay between viscoelasticity and inertia in dilute polymer solutions can lead to inertioelastic instabilities, resulting in elastoinertial turbulence (EIT) with distinct spatiotemporal features compared to Newtonian turbulence. Our study on a submerged planar jet of a dilute polymer solution in a quiescent water tank reveals that fluid elasticity has a nonmonotonic effect on the jet stability, creating two different regimes. At low levels of elasticity, an inertioelastic shear-layer instability emerges, destabilizing the flow and causing a turbulence transition closer to the nozzle. Increasing fluid elasticity merges the shear-layer instability into a bulk instability, partially stabilizing the flow and retarding the transition to turbulence. The fully turbulent state exhibits unique spatiotemporal features associated with EIT, characterized by self-similar evolution of jet spreading angle, entrainment, and coherent structures elongated in the streamwise direction. LDV measurements show a frequency spectrum with a -3 power-law exponent, different from Newtonian turbulence's well-known -5/3 exponent.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Nanoscience & Nanotechnology
Jake Song, Sungjin Kim, Olivia Saouaf, Crystal Owens, Gareth H. McKinley, Niels Holten-Andersen
Summary: This study presents a novel design strategy for the synthesis of high-concentration soft magnetic hydrogels by in situ mineralization of iron oxide nanoparticles within polymer hydrogels. The resulting hydrogels exhibit softness, viscoelasticity, and strong magnetic actuation, making them suitable for biomedical applications.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Mechanics
Simon J. Haward, Stylianos Varchanis, Gareth H. McKinley, Manuel A. Alves, Amy Q. Shen
Summary: Part I presents a microfluidic device for generating near-homogeneous uniaxial and biaxial elongational flows. In Part II, this device is used to examine the extensional rheology of dilute polymer solutions compared to measurements made under planar extension. The extension rate and tensile stress difference generated in the fluid are measured using micro-particle image velocimetry and excess pressure drop measurements. The results show that at higher polymer concentrations, the experimental measurements deviate from the model predictions due to intermolecular interactions as the polymer chains unravel in the extensional flows.
JOURNAL OF RHEOLOGY
(2023)
Article
Mechanics
San To Chan, Simon J. Haward, Eliot Fried, Gareth H. Mckinley
Summary: Saltwater taffy exhibits critical gel-like behavior and obeys time-temperature superposition principle. Its rheological properties can be described by the fractional Maxwell gel model. Minor ingredients like flavorings and colorings have little impact on the rheology of taffy.
Article
Multidisciplinary Sciences
Kyle R. Lennon, Gareth H. McKinley, James W. Swan
Summary: The development of data-driven models for complex fluid mechanics is essential for designing soft materials. This study presents a framework that allows rheologists to construct learnable models incorporating important physical information, without being dependent on specific experimental protocols or flow kinematics. These models enable rapid discovery of accurate constitutive equations from limited data and can describe more complex flows. The flexibility of this framework enables its application to a wide range of material systems and engineering problems.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Physical
Rishabh V. More, Reid Patterson, Eugene Pashkovski, Gareth H. McKinley
Summary: By studying the rod-climbing effect, we can measure the elasticity of complex fluids, including factors such as rotation rate, fluid elasticity, surface tension, and inertia. Our results show that by combining small amplitude oscillatory shear flow measurements and commercial rheometer measurements, we can accurately measure the normal stress differences of complex fluids.
Article
Chemistry, Physical
Joshua David John Rathinaraj, Kyle R. Lennon, Miguel Gonzalez, Ashok Santra, James W. Swan, Gareth H. McKinley
Summary: Clay slurries are widely used in the oil exploration industry as drilling fluids. However, modeling the rheological behavior of these suspensions is challenging due to their thermal-driven evolution and non-linear viscoelastic properties. This study presents a new approach for modeling the linear viscoelastic response of aging bentonite suspensions, which effectively solves the problem by transforming the time domain and material domain. Experimental measurements support the validity of this model.
Review
Chemistry, Physical
Jake Song, Niels Holten-Andersen, Gareth H. Mckinley
Summary: This study introduces the non-Maxwellian linear stress relaxation observed in soft matter systems and discusses its physical origins. Suitable mathematical models are proposed to describe this phenomenon. The research is important for understanding and modeling the mechanical relaxation of soft materials.
