Article
Mechanics
Bin Jiang, Cheng Li, Yan Yang, Kangcheng Zhou, William H. Matthaeus, Minping Wan
Summary: In the presence of anisotropy, the widespread use of the isotropic form of the third-order law to estimate energy transfer rates is questionable. On the other hand, the direction-averaged third-order structure function properly accounts for the effect of anisotropy and accurately predicts the energy transfer rates and inertial range.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
L. Djenidi, R. A. Antonia
Summary: The study shows that there are differences in the solutions of the Karman-Howarth equation between forced turbulence and decaying turbulence, mainly due to the generation of large-scale motions in forced turbulence. As the Reynolds number increases, the impact of forcing on small scales decreases, allowing the KHEq solutions to agree well with spectrally based solutions at scales unaffected by forcing.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Hanxun Yao, Tamer A. Zaki, Charles Meneveau
Summary: Based on the generalized local Kolmogorov-Hill equation, this study examines the definition of entropy and entropy generation for turbulence. The results from direct numerical simulations confirm the validity of the fluctuation relation in non-equilibrium thermodynamics for turbulent flows in the inertial range.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Krzysztof A. Mizerski
Summary: The magnetohydrodynamic (MHD) turbulence is present in both engineering laboratory flows and natural systems. It has the ability to generate and sustain large-scale and small-scale magnetic fields, playing a crucial role in processes such as nuclear fusion energy production. The turbulence also enhances large-scale diffusion and affects the energy and helicity spectra of strongly turbulent flows.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Maurizio Carbone, Michael Wilczek
Summary: Statistically homogeneous flows follow exact kinematic relations, with the Betchov homogeneity constraints being one of the most well-known and extensively used homogeneity relations. These relations have significant implications for the dynamics of fluids and turbulent energy cascade.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
Yan Yang, Minping Wan, William H. Matthaeus, Shiyi Chen
Summary: In studies of compressible magnetohydrodynamic (MHD) turbulence, it was found that compressive kinetic and thermal energy exchange is driven by acoustic waves through pressure dilatation, while exchange between kinetic and magnetic energy is dominated by interactions involving solenoidal velocity. Systematic rapid adjustments were found to be reproducible with simple scalings derived from empirical data.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Daniel Clark, Andres Armua, Richard D. J. G. Ho, Arjun Berera
Summary: Through numerical simulations, the study explores homogeneous and isotropic turbulence in higher spatial dimensions, focusing on chaos and predictability. The results reveal a transition to a non-chaotic regime above a critical dimension of approximately 5.88, highlighting the significance of Kolmogorov's 1941 theory in the context of turbulence properties.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Alberto Vela-Martin, Javier Jimenez
Summary: This paper analyzes the turbulent energy cascade from the perspective of statistical mechanics, testing the microscopical reversibility of the cascade and studying the origin of statistical irreversibility and the prevalence of direct and inverse energy cascades.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Miguel P. Encinar
Summary: Three-dimensional turbulent flows enhance velocity gradients through strong nonlinear interactions. The 'Betchov' relations define a length scale, and it is found that isotropic cascade models need not distinguish between vortex stretching and strain self-amplification.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Miguel P. Encinar, Javier Jimenez
Summary: The algorithm introduced by Jimenez (J. Fluid Mech., vol. 854, 2018, R1) is used to identify the flow patterns of causal significance in three-dimensional isotropic turbulence. The study finds that the dimensions of the perturbations introduced in the flow are controlled by the kinetic energy content and the enstrophy and dissipation, and affect their significance in the flow. Strain is found to be more efficient than vorticity in propagating the perturbation contents to other regions of the flow. The findings suggest that manipulating strain-dominated vortex clusters is more effective in controlling turbulent flows.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Takeshi Matsumoto, Michio Otsuki, Takeshi Ooshida, Susumu Goto
Summary: We studied the correlation function and mean linear response function of velocity Fourier mode of statistically steady-state, homogeneous and isotropic turbulence in Eulerian and Lagrangian coordinates through direct numerical simulation. The relation between the two functions was found to be disproportional, contrary to the fluctuation-dissipation theorem. Characteristic times associated with the functions were identified and compared between Eulerian and Lagrangian coordinates, showing different scalings in the inertial range.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Kazuhiro Inagaki
Summary: This study investigates the impact of helicity on scale-similar structures of turbulence, revealing that the energy cascade process in the scale-similar range is completely independent of helicity. Additionally, it is found that the helicity cascade is slightly non-local in scales compared to the energy cascade.
JOURNAL OF FLUID MECHANICS
(2021)
Review
Mechanics
S. M. Tobias
Summary: This paper introduces dynamo theory for fluid dynamicists, discussing the challenges and progress in the field. It argues that future advancements in dynamo theory will be built upon current breakthroughs in neutral fluid turbulence.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Xiangjun Wang, Minping Wang, Luca Biferale
Summary: This study investigates the accelerations of tracer and light particles in compressible homogeneous isotropic turbulence. The results show that the characteristics of acceleration vary for tracer particles and bubbles, and are closely related to the flow structures.
JOURNAL OF FLUID MECHANICS
(2022)
Article
Mechanics
A. Ababaei, B. Rosa, J. Pozorski, L. -P. Wang
Summary: This study investigates the dynamics of inertial particles in turbulence and found that considering lubrication forces and gravity can affect the relative velocities and distribution functions of particles in the near-contact region. However, the effect is minimal away from contact regions, and mass loading significantly impacts collision statistics.
JOURNAL OF FLUID MECHANICS
(2021)
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Mechanics
J. -H. Xie, J. Vanneste
JOURNAL OF FLUID MECHANICS
(2015)
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Astronomy & Astrophysics
Jin-Han Xie, Keith Julien, Edgar Knobloch
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2018)
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Physics, Fluids & Plasmas
Benjamin Miquel, Jin-Han Xie, Nicholas Featherstone, Keith Julien, Edgar Knobloch
PHYSICAL REVIEW FLUIDS
(2018)
Article
Mechanics
Jin-Han Xie, Oliver Buhler
JOURNAL OF FLUID MECHANICS
(2018)
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Physics, Fluids & Plasmas
Jin-Han Xie, Jacques Vanneste
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Mechanics
Jin-Han Xie, Jacques Vanneste
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Mechanics
Jin-Han Xie, Keith Julien, Edgar Knobloch
JOURNAL OF FLUID MECHANICS
(2019)
Article
Mechanics
Jin-Han Xie, Oliver Buhler
JOURNAL OF FLUID MECHANICS
(2019)
Article
Mechanics
Jin-Han Xie, Jacques Vanneste
JOURNAL OF FLUID MECHANICS
(2017)
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Physics, Fluids & Plasmas
Jin-Han Xie, Benjamin Miquel, Keith Julien, Edgar Knobloch