Article
Mechanics
Naveen Rohilla, Partha S. Goswami
Summary: This article explores the variation of local isotropy of fluid fluctuations and the decrease of the Kolmogorov constant in particle-laden turbulent channel flows. The author also adopts a new modeling technique using large-eddy simulation (LES) to predict fluid phase statistics without solving simultaneous particle phase equations. This study provides insights into the phenomena of drastic collapse in turbulence intensity.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Yan Xia, Zhaosheng Yu, Zhaowu Lin, Yu Guo
Summary: This study establishes correlations between the interfacial terms and the fluid dissipation rate equation and Reynolds stress equations in particle-laden flows, providing an accurate mathematical model and method for simulating particle-induced turbulence.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Duan Z. Zhang
Summary: This study establishes a relationship between ensemble average and nearest particle statistics to study long-range particle interactions and calculate particle sedimentation velocity. Additionally, it introduces an important particle-fluid-particle stress for general multiphase flows.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Jooyeon Park, Hyungmin Park
Summary: In this study, the effects of counter-rotating vortex pairs on particle dispersion patterns in a particle-laden upward jet with a horizontal crossflow were experimentally investigated. The results showed that the dynamics of the flow, influenced by the velocity ratio and particle Stokes number, play a crucial role in particle dispersion. Counter-rotating vortex pairs above the jet exit were found to significantly affect the movement of particles, with different regimes of particle dispersion identified based on Stokes number and velocity ratio.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Cheng-Hsien Lee
Summary: This study developed a multiphase model with a novel evolution equation to address the issues of shear-induced volume change and pore-pressure feedback in submarine granular flows simulated using an Eulerian-Eulerian two-phase model. The evolution equation effectively describes the relaxation process of static solid pressure and shear-induced volume change, allowing the model to capture phenomena such as time delays in initiating flows and different collapse processes for differently packed columns.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Electrical & Electronic
Nicolas Rasmont, Hussein Al-Rashdan, Gregory Elliott, Joshua Rovey, Laura Villafane
Summary: This paper presents a novel method for measuring the concentration of particles in optically opaque particle-laden flows. The method utilizes millimeter wave interferometry to measure the path-integrated particle concentrations using a fully-integrated FMCW radar. The instrument is capable of high-speed and quantitative measurements in dispersed multiphase flows with higher concentrations than existing optical methods. Calibration and validation experiments demonstrate the effectiveness of the measurement concept.
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
(2023)
Article
Mechanics
Holger Grosshans, Claus Bissinger, Mathieu Calero, Miltiadis Papalexandris
Summary: Through direct numerical simulations, we found that under certain density ratios and Coulombic-to-gravitational force ratios, electrostatic forces play a dominant role in the vortical motion of particles, affecting their distribution within the duct.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Meisam Pourali, Nick O. Jaensson, Martin Kroeger
Summary: Translation of a non-spherical particle trapped at a membrane or at a complex interface between fluids is a relevant situation occurring in biological, technological and everyday life systems. The resistance experienced by prolate spheroidal particles at a viscous interface can both rise or decrease with particle size depending on the dimensionless Boussinesq and Marangoni numbers. The distribution of surfactant in the vicinity of the moving spheroid is significantly affected by the particle's immersion depth at a surfactant-laden interface.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Xinchen Zhang, Graham J. Nathan, Zhao F. Tian, Rey C. Chin
Summary: Numerical simulations were used to identify the dominant mechanism driving secondary flow motions in horizontal particle-laden pipe flows. Different flow regimes and their corresponding secondary flow structures were characterized by varying the mass loading. Analysis of forces acting on the fluid phase and particle phase helped explain the secondary flows and their interactions.
JOURNAL OF FLUID MECHANICS
(2022)
Review
Multidisciplinary Sciences
Aleksey Yu. Varaksin, Sergei V. Ryzhkov
Summary: This paper reviews computational-theoretical and experimental works on the flow of bodies in two-phase (dispersed) flows. The motion of particles near bodies of different shapes, as well as the impact of the dispersed phase on resistance and heat transfer, are discussed. The consequences of particle and droplet interaction with the surface of streamlined bodies (erosive destruction, gas-dynamic spraying, icing, glowing) are also analyzed.
Article
Mechanics
S. Beetham, R. O. Fox, J. Capecelatro
Summary: In this study, model closures for multiphase Reynolds-averaged Navier-Stokes (RANS) equations are developed using sparse regression and Eulerian-Lagrangian simulations to ensure accuracy and robustness of the models across different flow conditions. The focus is on capturing the dynamics of gas-particle flows, particularly the generation of particle clusters and interphase momentum exchange, in a compact and algebraic manner.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Darish Jeswin Dhas, Anubhab Roy
Summary: In this paper, the role of shear-induced migration and particle-induced normal stresses in the formation and stability of a particle-laden, gravity-driven shallow flow is studied. Through experiments and analysis, it is found that shear-induced migration leads to viscosity stratification and affects the development of the boundary layer formation in different conditions. It is also observed that increasing bulk particle concentration delays the onset of instability when the associated Peclet number is small, but enhances both modes of instability when the Peclet number is large. Additionally, it is shown that beyond a critical Peclet number, the surface mode becomes unstable even in the absence of fluid inertia.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Engineering, Multidisciplinary
Kerlyns Martinez Rodriguez, Mireille Bossy, Radu Maftei, Seyedafshin Shekarforush, Christophe Henry
Summary: This article presents a new data-driven spatial decomposition algorithm that allows for the splitting of a domain containing point particles into elementary cells with spatially-uniform distributions of particles. By using statistical information, the algorithm extracts an optimal spatial decomposition, providing more accurate and mesh-independent predictions for studying particle agglomeration.
APPLIED MATHEMATICAL MODELLING
(2021)
Article
Mechanics
Sofia Angriman, Amelie Ferran, Florencia Zapata, Pablo J. Cobelli, Martin Obligado, Pablo D. Mininni
Summary: This study investigates the three-dimensional clustering of velocity stagnation points, vorticity nulls, and inertial particles in turbulent flows with different large-scale flow geometries by combining direct numerical simulations and particle tracking velocimetry. The results show that although the flows have different topologies in terms of null clustering, the behavior of particles is similar in all cases, indicating the clustering of Taylor-scale neutrally buoyant particles as inertial particles.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Xiaojing Zheng, Guohua Wang, Wei Zhu
Summary: This study investigates the influence of the interaction between heavy particles (high Stokes number) and the wall on two-phase flows and large-scale turbulent structures. Experimental results confirm that the P-W process significantly affects the size and strength of VLSM.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Computer Science, Interdisciplinary Applications
A. Baraldi, M. S. Dodd, A. Ferrante
COMPUTERS & FLUIDS
(2014)
Article
Computer Science, Interdisciplinary Applications
Michael S. Dodd, Antonino Ferrante
JOURNAL OF COMPUTATIONAL PHYSICS
(2014)
Article
Mechanics
F. Lucci, V. S. L'vov, A. Ferrante, M. Rosso, S. Elghobashi
THEORETICAL AND COMPUTATIONAL FLUID DYNAMICS
(2014)
Article
Mechanics
Andreas Freund, Antonino Ferrante
JOURNAL OF FLUID MECHANICS
(2019)
Article
Physics, Fluids & Plasmas
Michael S. Dodd, Lluis Jofre
PHYSICAL REVIEW FLUIDS
(2019)
Article
Thermodynamics
Michael S. Dodd, Danyal Mohaddes, Antonino Ferrante, Matthias Ihme
Summary: This study conducted DNS of evaporation of n-heptane fuel droplets in forced homogeneous isotropic turbulence and carried out a parametric study. The results showed that increasing the liquid volume fraction of droplets decreases the evaporation rate and causes deviation from the classical law.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Mechanics
Andreas Freund, Antonino Ferrante
Summary: The proposed MANN LES method effectively simulates turbulent flows laden with droplets by utilizing artificial neural networks to predict the subgrid-scale (SGS) closure terms at the interface. This approach demonstrates good reproduction performance under different Weber numbers for droplets.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Mechanics
I. Paul, B. Fraga, M. S. Dodd, C. C. K. Lai
Summary: The second part of this research examines the kinematic aspect of fine-scale bubble-induced turbulence (BIT) and compares it to universal kinematic fine-scale turbulence characteristics. The study reveals that BIT is significantly different from classical homogeneous isotropic turbulence (HIT) and that bubble breakup and coalescence have little influence on the kinematics of fine-scale BIT.
Article
Mechanics
Shao-Chi Huang, Abhiram B. Aithal, Antonino Ferrante
Summary: Lu, Aithal, and Ferrante have discovered a law that accurately predicts the incipience of flow separation over curved ramps by knowing only a few geometrical parameters and Reynolds number. They performed simulations and validation, and investigated the effects of angle of attack, airfoil thickness, and camber on flow separation incipience. They proposed a new law based on characteristics slope, thickness, camber, and Reynolds number for predicting flow separation incipience over airfoils.
Article
Mechanics
I. Paul, B. Fraga, M. S. Dodd, C. C. K. Lai
Summary: This study investigates the impact of bubble breakup and coalescence on the fine-scale dynamics of bubbly turbulent flows using direct numerical simulations. The results reveal that bubble-induced turbulence exhibits different velocity gradient behavior compared to classical homogeneous isotropic turbulence, suggesting the need for new velocity gradient models. The study also suggests that the effects of bubble topology, breakup, and coalescence can be neglected when studying or modeling the fine-scale dynamics of bubbly turbulent flows.
Article
Computer Science, Interdisciplinary Applications
Abhiram B. Aithal, Mira Tipirneni, Antonino Ferrante
Summary: FastRK3 is an explicit, third-order Runge-Kutta (RK3) based projection method for solving the incompressible Navier-Stokes equations in curvilinear coordinates. It requires solving the pressure Poisson equation only once per time step, which is less than the standard RK3 methodology. The temporal accuracy of FastRK3 is theoretically derived and numerically verified for different flow types.
JOURNAL OF COMPUTATIONAL PHYSICS
(2023)
Article
Computer Science, Interdisciplinary Applications
Abhiram B. Aithal, Antonino Ferrante
JOURNAL OF COMPUTATIONAL PHYSICS
(2020)