Article
Mechanics
F. Faisant, B. Besga, A. Petrosyan, S. Ciliberto, Satya N. Majumdar
Summary: This study experimentally investigates the optimal mean time for a Brownian particle to reach a target with resetting in one or two dimensions. Different resetting protocols were derived and tested, revealing a phase transition at a critical value, with calculations, experimental setup, and limitations discussed.
JOURNAL OF STATISTICAL MECHANICS-THEORY AND EXPERIMENT
(2021)
Article
Energy & Fuels
Shahide Sayadian, Majid Ghassemi, Sadegh Ahmadi, Anthony James Robinson
Summary: This paper presents a dimensionless approach to studying the transport phenomena in the gas channels of SOFCs, providing generalized results for similar fuel cells. The efficacy of the computational fluid dynamic model is confirmed by comparing simulated results with experimental data, and the influence of dimensionless parameters in fuel and air channels on cell performance is discussed.
Article
Mechanics
Pedro Paraguassu, Welles A. M. Morgado
Summary: This paper analytically derives the expression for the distribution of heat in a diffusive system in a logarithm potential through path integral. The found distribution is applied to the first passage problem, resulting in unexpected results for the reversibility of the distribution and a fluctuation theorem under specific conditions of the strength parameters.
JOURNAL OF STATISTICAL MECHANICS-THEORY AND EXPERIMENT
(2021)
Article
Thermodynamics
Jiaqi Luo, Qiang Zhou, Tao Jin
Summary: A computational fluid dynamics (CFD) model is developed to simulate the nonlinear phenomena in a gas-liquid standing-wave thermoacoustic engine. The model accurately predicts the onset and steady-state performances of the experimental system. The nonlinear dynamic and acoustic phenomena of the engine are analyzed, as well as the multi-dimensional flow effect and mass streaming.
APPLIED THERMAL ENGINEERING
(2022)
Article
Engineering, Marine
Yoon-Jin Ha, Kyong-Hwan Kim, Ji-Yong Park
Summary: In this study, the non-linear physical phenomena of a tension leg platform (TLP) for a 15-MW-class floating offshore wind turbine (FOWT) were investigated through numerical simulation. Computational fluid dynamics and a deforming mesh technique were used to simulate the effects of irregular waves on the structure, and the relations between springing and ringing responses were investigated. The study also conducted whipping simulations to examine the response in pitch resonance frequency caused by wave impact.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Materials Science, Multidisciplinary
Yong-Joon Lee, Kyung-Woo Yi
Summary: The study developed a new impeller profile to enhance the desulfurization efficiency of the Kanbara reactor (KR) process, based on operational data analysis and computational fluid dynamics simulation. The new impeller design was tested on-site and successfully improved industrial desulfurization efficiency, as confirmed by the results of over 350 charges.
METALS AND MATERIALS INTERNATIONAL
(2022)
Article
Energy & Fuels
Karol K. Sreniawski, Marcin Mozdzierz, Grzegorz Brus, Janusz S. Szmyd
Summary: This study presents a computational fluid dynamic simulation of a solid oxide fuel cell stack for enhancing its geometrical design. A mathematical model including momentum, heat, mass, and charge transport phenomena was developed and validated against experimental study. The proposed design modifications led to an increase in the volumetric power density of the stack compared to the existing prototype design, and the proposed models were shown to be useful for testing further design modifications and performance analysis.
Article
Chemistry, Physical
Thomas Thelen, Adriana Jara, Isaac Torres-Diaz
Summary: We investigate the dipole-dipole interaction and shape anisotropy in suspensions of anisotropic particles with permanent magnetization. Using an ellipsoid-dipole model, we quantify the dipolar interaction energy between particles of similar or dissimilar shapes. Monte Carlo simulations show that these interactions and shape anisotropy lead to the formation of dendritic and barbed-wire structures in uniform ellipsoids and binary mixtures, respectively. Additionally, the interplay between entropic and energy interactions reduces the magnetic response of binary suspensions.
Article
Chemistry, Physical
Guo-Jun Liao, Sabine H. L. Klapp
Summary: Using BD simulations, we investigated the self-organization of a monolayer of chiral active particles with dipolar interactions. Despite performing simulations at high dipolar coupling strength and low density, we observed phenomena such as vortex formation, phase separation, and flocking transitions in the system. We further studied the dynamics of simple ring structures under the impact of self-propulsion to understand the appearance and disappearance of vortices.
Article
Mathematics
Song-Kyoo (Amang) Kim
Summary: This article analyzes the behavior of a Brownian fluctuation process under a mixed strategic game setup and proposes a new variant of a compound Brownian motion to predict turning points of a stochastic process. Analytically tractable results are obtained using fluctuation theory and mixed strategy game theory, which are applied in implementing an autonomous trader.
Article
Green & Sustainable Science & Technology
Ziwen Chen, Xiaodong Wang, Yize Guo, Shun Kang
Summary: This study investigates the aerodynamic characteristics of floating offshore wind turbines under different motions using computational fluid dynamics simulations. It is found that increasing amplitude and frequency can aggravate the fluctuation of the overall aerodynamic performance of wind turbines. Additionally, complex platform motions adversely affect the power generation of floating offshore wind turbines.
Article
Engineering, Chemical
Tianhao Tang, Wanyi Fu, Xihui Zhang
Summary: This paper establishes a hydrodynamic model of a ceramic membrane channel to study the factors influencing fluid flow and desalination efficiency, and finds that the external potential and the zeta potential of the membrane material have significant effects on the desalination process.
Article
Mechanics
Guitian He, Guoji Tang, Yan Tian, Maokang Luo, H. Eugene Stanley
Summary: This work investigates the statistical properties of charged-particle motion in a microwave field and a magnetic field with a general direction using a generalized Langevin equation with intrinsic noise. The study focuses on drift velocity, complex susceptibilities, spectral amplification, stationary current density, and power absorption. It is notable that stochastic dynamics of charged particles can be induced by fractional Gaussian noise, and variances and covariances are studied based on relationships between relaxation functions and memory kernel functions.
JOURNAL OF STATISTICAL MECHANICS-THEORY AND EXPERIMENT
(2021)
Article
Mechanics
F. R. Cunha, Y. Z. Sinzato, I. D. O. Pereira
Summary: In this study, experimental evidence is provided to support the description of the magnetoviscous effect of a ferrofluid as a suspension of ellipsoidal particles. The findings are important for understanding the flow behavior of magnetic fluids in shear and pipe flows, which has practical applications in lubrication and magnetic sealing.
Article
Energy & Fuels
Gonca Gormez, Bilge Albayrak ceper
Summary: The numerical analysis of the Continental AVDS 1790-2A tank engine in RCCI combustion mode was conducted with different parameters, with the values closest to conventional diesel combustion pressure obtained at lambda = 2.5, EGR = 30%, and SOI = 340 degrees CA.
Article
Mechanics
Mihir Durve, Adriano Tiribocchi, Fabio Bonaccorso, Andrea Montessori, Marco Lauricella, Jan Guzowski, Sauro Succi
Summary: Deep neural networks are powerful tools for data analysis in microfluidic systems, particularly in droplet counting and tracking. This study combines the YOLO and DeepSORT algorithms to create the image analysis tool DropTrack for droplet tracking in microfluidic experiments. Training the YOLO network with hybrid datasets improves the accuracy of droplet detection and counting in real experimental videos, while reducing the labor-intensive image annotation work. DropTrack's performance is evaluated based on mean average precision, mean squared error, and image analysis speed for droplet tracking.
Article
Mechanics
Valentina Lombardi, Michele La Rocca, Andrea Montessori, Sauro Succi, Pietro Prestininzi
Summary: Droplets impacting solid surfaces and jumping over gaps are common phenomena in both natural and industrial environments. Through experiments, it has been found that droplets can deform upon impact and climb sharp edges. This unique behavior is attributed to the conversion of rotational momentum into linear momentum. The study shows that droplets are more likely to jump over gaps compared to solid spheres. This research contributes to the understanding of the rotational speed of droplets on hydrophobic surfaces.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Yanbiao Gan, Aiguo Xu, Huilin Lai, Wei Li, Guanglan Sun, Sauro Succi
Summary: This paper aims to formulate and validate a multi-scale discrete Boltzmann method based on density functional kinetic theory for thermal multiphase flow systems. It also provides new insights into the thermo-hydrodynamic non-equilibrium effects in the phase separation process.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Physics, Fluids & Plasmas
Ya Gai, Andrea Montessori, Sauro Succi, Sindy K. Y. Tang
Summary: This article explores the collective behavior of drops in a concentrated emulsion and reveals the physics of drops under different flow velocities. At slow flow rates, drops exhibit spatiotemporal periodicity in the emulsion, while at fast flow rates, droplet breakup occurs following a probability distribution. The use of nanoparticles as droplet stabilizers enhances droplet processing throughput.
PHYSICAL REVIEW FLUIDS
(2022)
Article
Physics, Multidisciplinary
Pablo G. Tello, D. O. N. A. T. O. Bini, S. T. U. A. R. T. Kauffman, S. A. U. R. O. Succi
Summary: This letter proposes an approach to the vacuum energy and the cosmological constant (CC) paradox based on the Zel'dovich's ansatz, which states that the observable contribution to the vacuum energy density is given by the gravitational energy of virtual particle-antiparticle pairs. The novelty of this work is the use of an ultraviolet cut-off length based on the holographic principle, which yields current values of the CC in semi-quantitative agreement with experimental observations.
Article
Physics, Mathematical
Daniele Simeoni, Alessandro Gabbana, Sauro Succi
Summary: In this work, we provide both analytic and numerical solutions for the Bjorken flow, which is a standard benchmark in relativistic hydrodynamics. It offers a simple model for the macroscopic evolution of matter produced in heavy nucleus collisions. We consider relativistic gases with both massive and massless particles, working in a (2+1) and (3+1) Minkowski spacetime coordinate system. The numerical results obtained from a newly developed lattice kinetic scheme show excellent agreement with the analytic solutions.
COMMUNICATIONS IN COMPUTATIONAL PHYSICS
(2023)
Article
Physics, Mathematical
Giacomo Falcucci, Giorgio Amati, Pierluigi Fanelli, Sauro Succi, Maurizio Porfiri
Summary: This study investigates the flow characteristics of the Hexactinellid Sponge Euplectella aspergillum using large-scale simulations. The findings reveal the evolutionary adaptations of deep-sea sponges to fluid flow and open up new possibilities for interdisciplinary research in physics, engineering, and biology at the ocean interface.
COMMUNICATIONS IN COMPUTATIONAL PHYSICS
(2023)
Article
Chemistry, Physical
Mihir Durve, Sibilla Orsini, Adriano Tiribocchi, Andrea Montessori, Jean-Michel Tucny, Marco Lauricella, Andrea Camposeo, Dario Pisignano, Sauro Succi
Summary: Tracking droplets in microfluidics is a challenging task, and choosing a tool to analyze microfluidic videos is difficult. The YOLO and DeepSORT algorithms are used for droplet identification and tracking by training networks. Several YOLOv5 and YOLOv7 models and the DeepSORT network were trained for droplet tracking. Performance comparison between YOLOv5 and YOLOv7 in terms of training time and video analysis time was conducted. Real-time tracking was achieved with lighter YOLO models on RTX 3070 Ti GPU due to additional droplet tracking costs from the DeepSORT algorithm. This work serves as a benchmark study for YOLOv5 and YOLOv7 networks with DeepSORT for microfluidic droplet analysis.
EUROPEAN PHYSICAL JOURNAL E
(2023)
Article
Chemistry, Physical
Adriano Tiribocchi, Andrea Montessori, Giorgio Amati, Massimo Bernaschi, Fabio Bonaccorso, Sergio Orlandini, Sauro Succi, Marco Lauricella
Summary: A regularized version of the lattice Boltzmann method is proposed for efficient simulation of soft materials. It reconstructs the distribution functions from available hydrodynamic variables without storing the full set of discrete populations, leading to lower memory requirements and data access costs. Benchmark tests validate the method's effectiveness for simulating soft matter systems, particularly on future exascale computers.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Mechanics
Praveen Kumar Kolluru, Mohammad Atif, Santosh Ansumali
Summary: Kinetic models of polyatomic gas often consider internal degrees of freedom using the two-particle distribution function. However, near the hydrodynamic limit, the rotational degrees of freedom can be adequately represented by rotational kinetic energy density. We introduce an extension of the ellipsoidal statistical Bhatnagar-Gross-Krook (ES-BGK) model which includes an advection-diffusion-relaxation equation for rotational energy at the single-particle distribution function level. This reduced model satisfies the H theorem and recovers compressible hydrodynamics for polyatomic gases in its macroscopic limit. Additionally, the extension of the ES-BGK model allows for three independent tunable transport coefficients: thermal conductivity, shear viscosity, and bulk viscosity. The effectiveness of the model is demonstrated through a lattice Boltzmann method implementation.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
A. Tiribocchi, M. Durve, M. Lauricella, A. Montessori, D. Marenduzzo, S. Succi
Summary: Active droplets are artificial microswimmers that exhibit self-propelled motion. The authors study the effect of activity on a droplet containing a contractile polar fluid confined within microfluidic channels of various sizes. They find a range of shapes and dynamic regimes, regulated by contractile stress, droplet elasticity, and microchannel width.
Article
Physics, Particles & Fields
Andrea Solfanelli, Stefano Ruffo, Sauro Succi, Nicolo Defenu
Summary: In this study, we investigate the asymptotic behavior of the entanglement entropy for Kitaev chains with long-range hopping and pairing couplings. We find that the system exhibits an extremely rich phenomenology due to its truly non-local nature. In the strong long-range regime, we observe logarithmic, fractal, or volume-law entanglement scaling depending on the values of the chemical potential and power law decay strength.
JOURNAL OF HIGH ENERGY PHYSICS
(2023)
Article
Astronomy & Astrophysics
Donato Bini, Stuart Kauffman, Pablo G. Tello, Sauro Succi
Summary: In this study, we compute the metric fluctuations induced by a turbulent energy-matter tensor within the first order post-Minkowskian approximation. We find that the turbulent energy cascade can interfere with the process of black hole formation and exhibit a potentially strong coupling between these two highly nonlinear phenomena. Furthermore, we discover that the power-law turbulent energy spectrum determines the scaling of metric fluctuations as xn-2, with x representing the four-dimensional spacelike distance in Minkowski spacetime and highlighting metric singularities when n < 2. Finally, we discuss the effect of metric fluctuations on the geodesic motion of test particles as a potential technique to extract information on the spectral characteristics of fluctuating spacetime.
Article
Mathematics
Mihir Durve, Andriano Tiribocchi, Andrea Montessori, Marco Lauricella, Sauro Succi
Summary: This work analyzes the trajectories obtained from YOLO and DeepSORT algorithms in dense emulsion systems simulated using lattice Boltzmann methods. The findings reveal that the direction of individual droplets is more influenced by those immediately behind rather than in front of them. The analysis also provides insights into the constraints of a dynamical model for dense emulsions in narrow channels.
COMMUNICATIONS IN APPLIED AND INDUSTRIAL MATHEMATICS
(2022)
Article
Physics, Fluids & Plasmas
Harald Schmid, Johannes Dieplinger, Andrea Solfanelli, Sauro Succi, Stefano Ruffo
Summary: In this study, we generalize the classical Hamiltonian mean-field model to fermionic particles and investigate the phase diagram and thermodynamic properties of the model under ferromagnetic interactions. The system exhibits different quantum phase transition behaviors at different temperatures and a tricritical point is observed in a quantum system with long-range couplings.
