Physical Review E
Numerical search for states with constant enstrophy flux over finite time intervals in two-dimensional turbulence
Author(s): Kyo Yoshida
An ensemble model of turbulence based on states with constant flux in wavenumber space was proposed in [K. Yoshida, Phys. Rev. E 106, 045106 (2022)]. The justification of this ensemble model relies on the conjecture that almost all states with constant flux correspond to turbulence states. To verify…
[Phys. Rev. E 113, 065101] Published Mon Jun 01, 2026
Droplet shrinkage in phase-field approaches: A comparison of the Allen-Cahn and the Cahn-Hilliard models
Author(s): Reza Haghani, Carl Fredrik Berg, and Eirik Grude Flekkøy
Diffuse interface methods for multiphase flow simulations often exhibit nonphysical droplet or bubble shrinkage, particularly when based on the Cahn-Hilliard equation. This well-known artifact introduces a critical radius below which droplets vanish, thereby limiting the fidelity of simulations invo…
[Phys. Rev. E 113, 055107] Published Mon May 18, 2026
Electrolyte flows under magnetic fields: Manning-like counterion condensation in one dimension
Author(s): Yoav Tsori and Hannes Uecker
We present a theoretical framework for unidirectional electromagnetohydrodynamic flow of dilute electrolytes under perpendicular magnetic fields. Starting from the Navier-Stokes equation coupled with the Poisson-Nernst-Planck formulation, we show that the problem admits a sequential decoupling: the …
[Phys. Rev. E 113, 055105] Published Mon May 11, 2026
Capillarity in stationary random granular media: Distribution-aware screening and quantitative supercell sizing
Author(s): Christian Tantardini and Fernando Alonso-Marroquín
We develop a quantitative framework to determine the minimal periodic supercell required for representative simulations of capillarity-screened Darcy flow in stationary random, polydisperse granular media. The microstructure is characterized by two-point statistics (covariance and spectral density) …
[Phys. Rev. E 113, 055106] Published Mon May 11, 2026
Interaction of walkers with a standing Faraday wave
Author(s): Loïc Tadrist and Tristan Gilet
Walkers (i.e., bouncing droplets coupled to a local Faraday wave) are sent on an orthogonal standing wave. The trajectories of successive walkers form a straight-propagating beam toward the wave that splits into three distinct paths during the interaction with the wave. At the end of the interaction…
[Phys. Rev. E 113, 055104] Published Fri May 08, 2026
Spatial dynamics of flexible nanoswimmers under a rotating magnetic field
Author(s): Chapnik Zvi and Or Yizhar
Micronanorobotic swimmers have promising potential for future biomedical tasks such as targeted drug delivery and minimally invasive diagnosis. An efficient method for controlled actuation of such nanoswimmers is applying a rotating external magnetic field, resulting in helical corkscrewlike locomot…
[Phys. Rev. E 113, 055103] Published Wed May 06, 2026
Mesoscale simulation model for odd fluids
Author(s): Yuxing Jiao and Mingcheng Yang
A fluid with broken time-reversal symmetry would exhibit odd transport coefficients, such as odd viscosity, thermal conductivity, and diffusion coefficient, which may fundamentally alter the fluid properties and significantly influence the structure and dynamics of immersed objects. Here, we develop…
[Phys. Rev. E 113, 055102] Published Tue May 05, 2026
Data-driven modeling of multiscale phenomena with applications to fluid turbulence
Author(s): Brandon Choi, Matteo Ugliotti, Mateo Reynoso, Daniel R. Gurevich, and Roman O. Grigoriev
This paper introduces a data-driven framework for constructing accurate and general equivariant models of multiscale phenomena which does not rely on specific assumptions about the underlying physics. This framework is illustrated using incompressible fluid turbulence as an example that is represent…
[Phys. Rev. E 113, 055101] Published Mon May 04, 2026
Quadratic Fokker-Planck model of monatomic rarefied gas
Author(s): Henan Zhang, Hao Yang, Ziqi Cui, and Jun Zhang
In recent years, significant progress has been made in Fokker-Planck (FP) approximations of the Boltzmann equation, where binary collisions are modeled as drift and diffusion processes in velocity space. To address the discrepancy in the Prandtl number for the original linear FP model, several modif…
[Phys. Rev. E 113, 045107] Published Tue Apr 28, 2026
Drag force and diffusion of small planar structures: A gas kinetic theory analysis and molecular dynamics study
Author(s): Amitesh S. Jayaraman, Nikolaos Kateris, and Hai Wang
The drag force on planar structures of arbitrary shape is derived in free molecular flow using gas kinetic theory. The theory is formulated by considering the anisotropic intermolecular potential between the particle and gas molecules, in the limits of specular and diffuse scatterings. The drag forc…
[Phys. Rev. E 113, 045106] Published Mon Apr 20, 2026
Relation of exact hydrodynamics to the Chapman-Enskog series
Author(s): Florian Kogelbauer and Ilya Karlin
We demonstrate that the Chapman-Enskog series is locally equivalent to the exact spectral closure defined on slow kinetic eigenmodes in the limit of vanishing Knudsen number. We further show that the Chapman-Enskog series diverges everywhere except at the global equilibrium for an explicit example, …
[Phys. Rev. E 113, 045105] Published Tue Apr 14, 2026
Emergence of vorticity and viscous stress in finite-scale quantum hydrodynamics
Author(s): Christopher Triola
The Madelung equations offer a hydrodynamic description of quantum systems, from single particles to quantum fluids. In this formulation, the probability density is mapped onto the fluid density and the phase is treated as a scalar potential generating the velocity field. As examples of potential fl…
[Phys. Rev. E 113, 045104] Published Mon Apr 13, 2026
Analytical solution for dynamic evaporation of liquid in isothermal condition
Author(s): Luiz Eduardo Czelusniak, Tim Niklas Bingert, Stephan Simonis, Alexander J. Wagner, and Mathias J. Krause
An analytical solution based on a diffuse-interface model is presented for an isothermal evaporation problem at subsaturated vapor pressure. The macroscopic equations are derived from the free-energy formulation widely used in the lattice Boltzmann literature, distinguishing our approach from conven…
[Phys. Rev. E 113, 045103] Published Fri Apr 10, 2026
Analysis of instantaneous skin friction in a supersonic turbulent boundary layer
Author(s): Rongji Hu, Zhikang Huang, Geng Zhao, Xue-Lu Xiong, Feng Liu, Jian Fang, and Yi Zhou
The generation of skin friction in a spatially evolving turbulent boundary layer at a Mach number Ma∞=2.9 is analyzed using direct numerical simulation (DNS). Particular attention is paid to clarifying the impact of the turbulent/nonturbulent interface (TNTI) height on the skin friction. In contrast…
[Phys. Rev. E 113, 045102] Published Tue Apr 07, 2026
Comprehensive interscale energy transfer in homogeneous isotropic turbulence
Author(s): Jun-Yang Li, Dong Sun, Si-Wei Dong, Peng-Xin Liu, and Xian-Xu Yuan
This study examines interscale energy transfer, conventionally denoted as the “energy cascade,” in forced homogeneous isotropic turbulence. By employing spatial filtering techniques, the turbulent kinetic energy is decomposed into distinct large- and small-scale components, as well as local- and sub…
[Phys. Rev. E 113, 045101] Published Wed Apr 01, 2026
Topological entropy of stationary three-dimensional turbulence
Author(s): Ankan Biswas, Amal Manoharan, and Ashwin Joy
Topological entropy serves as a viable candidate for quantifying mixing and complexity of a highly chaotic system. Particularly in turbulence, this is determined as the exponential stretching rate of a fluid material line that typically necessitates a Lagrangian description. We extend our recent wor…
[Phys. Rev. E 113, 035107] Published Mon Mar 30, 2026
Re-examining the boundary conditions in modeling surface-acoustic-wave-driven acoustofluidic streaming
Author(s): Qinran Wei, Suyu Ding, Yang Zhao, Yuanpeng Ma, Dachuan Sang, Dong Zhang, and Xiasheng Guo
Numerical simulations of surface acoustic wave (SAW)-induced acoustic streaming are highly sensitive to the choice of second-order boundary conditions. This study systematically compares the no-slip (NS) and Stokes slip (SD) boundary conditions through different numerical approaches. Two- and three-…
[Phys. Rev. E 113, 035105] Published Wed Mar 25, 2026
Quantum potential from the material derivative of the osmotic velocity: A two-fluid Madelung framework
Author(s): Lachezar S. Simeonov
We derive the quantum potential directly from the material derivative of the osmotic velocity and formulate a two-fluid model that reproduces the Madelung equations. Interactions between the two fluids are included but remain secondary. The framework is generalized to incorporate electromagnetic fie…
[Phys. Rev. E 113, 035106] Published Wed Mar 25, 2026
Suppressing viscous fingering with rotation: Linear predictions and nonlinear simulations
Author(s): Írio M. Coutinho and José A. Miranda
In this work, we investigate the possibility of suppressing injection-driven, viscous fingering instabilities in a radial Hele-Shaw cell, via the action of centrifugal forces. We consider the situation in which an inviscid fluid of negligible density is injected into a viscous and denser one, while …
[Phys. Rev. E 113, 035103] Published Tue Mar 24, 2026
Flexible fiber studied in fluid flow using a variational method
Author(s): Haoyu Liu, Edidiong Michael Umana, and Xiufeng Yang
The interaction between flexible bodies and fluids is very complex, however, studying this mechanism helps us understand how natural plants deform in response to fluid flow to prevent structural damage. Due to the complexity of fluid-structure interaction, there is a lack of methods for quickly and …
[Phys. Rev. E 113, 035104] Published Tue Mar 24, 2026