Physical Review E

Author(s): Robert Fischer, Christian M. Schlepütz, Dirk Hegemann, René M. Rossi, Dominique Derome, and Jan Carmeliet

What are the mechanisms at play in the spontaneous imbibition dynamics in polyethylene terephthalate filament yarns at pore scale? Processes at pore scale such as waiting times between the filling of two neighboring pores, as observed in special irregular porous media, like yarns, may overrule the p...

[Phys. Rev. E 103, 053101] Published Mon May 10, 2021

Author(s): Jacob R. Gissinger, Alexander Z. Zinchenko, and Robert H. Davis

The internal flow and mixing properties inside deformable droplets, after reaching the steady state within two types of passive droplet traps, are visualized and analyzed as dynamical systems. The first droplet trap (constriction) is formed by three spheres arranged in an equilateral triangle, while...

[Phys. Rev. E 103, 043106] Published Wed Apr 28, 2021

Author(s): Itzhak Fouxon, Joshua Feinberg, and Michael Mond

We consider the evolution of arbitrarily large perturbations of a prescribed pure hydrodynamical flow of an electrically conducting fluid. We study whether the flow perturbations as well as the generated magnetic fields decay or grow with time and constitute a dynamo process. For that purpose we der...

[Phys. Rev. E 103, 043104] Published Mon Apr 26, 2021

Author(s): Daniel R. Guildenbecher, John J. Barnard, Thomas W. Grasser, Anthony M. McMaster, Robert B. Campbell, David P. Grote, Prabal Nandy, and Max Light

Evaporation of streams of liquid droplets in environments at vacuum pressures below the vapor pressure has not been widely studied. Here, experiments and simulations are reported that quantify the change in droplet diameter when a steady stream of ≈100 μm diameter drops is injected into a chamber in...

[Phys. Rev. E 103, 043105] Published Mon Apr 26, 2021

Author(s): Benjamin Favier

We consider the problem of an inextensible but flexible fiber advected by a steady chaotic flow, and ask the simple question of whether the fiber can spontaneously knot itself. Using a one-dimensional Cosserat model, a simple local viscous drag model and discrete contact forces, we explore the proba...

[Phys. Rev. E 103, 043101] Published Mon Apr 12, 2021

Author(s): Rahil N. Valani, Anja C. Slim, and Tapio P. Simula

Vertically vibrating a liquid bath at two frequencies, f and f/2, having a constant relative phase difference can give rise to self-propelled superwalking droplets on the liquid surface. We have numerically investigated such superwalking droplets in the regime where the phase difference varies slowl...

[Phys. Rev. E 103, 043102] Published Mon Apr 12, 2021

Author(s): Jonathan E. Higham, Mehrdad Shahnam, and Avinash Vaidheeswaran

We present our analysis on microrheology of a bench-scale pulsed fluidized bed, which represents a weakly confined system. Nonlinear gas-particle and particle-particle interactions resulting from pulsed flow are associated with harmonic and subharmonic modes. While periodic structured bubble pattern...

[Phys. Rev. E 103, 043103] Published Mon Apr 12, 2021

Author(s): Itzhak Fouxon, Joshua Feinberg, Petri Käpylä, and Michael Mond

The Navier-Stokes equations generate an infinite set of generalized Lyapunov exponents defined by different ways of measuring the distance between exponentially diverging perturbed and unperturbed solutions. This set is demonstrated to be similar, yet different, from the generalized Lyapunov exponen...

[Phys. Rev. E 103, 033110] Published Wed Mar 24, 2021

Author(s): John M. Kolinski and Tobias M. Schneider

Viral transmission pathways have profound implications for public safety; it is thus imperative to establish a complete understanding of viable infectious avenues. Mounting evidence suggests SARS-CoV-2 can be transmitted via the air; however, this has not yet been demonstrated. Here we quantitativel...

[Phys. Rev. E 103, 033109] Published Mon Mar 22, 2021

Author(s): Hanna Rademaker, Kaare H. Jensen, and Tomas Bohr

We study the viscous dissipation in pipe flows in long channels with porous or semipermeable walls, taking into account both the dissipation in the bulk of the channel and in the pores. We give simple closed-form expressions for the dissipation in terms of the axially varying flow rate Q(x) and the ...

[Phys. Rev. E 103, 033108] Published Fri Mar 19, 2021

Author(s): Peter V. Gordon, Leonid Kagan, and Gregory Sivashinsky

The nature of thermonuclear explosions of white-dwarf stars is a fundamental astrophysical issue, the first principle interpretation of which is still commonly regarded as an unresolved problem. There is a general consensus that stellar explosions are a manifestation of the deflagration-to-detonatio...

[Phys. Rev. E 103, 033106] Published Wed Mar 17, 2021

Author(s): F. Sultanov, M. Sultanova, G. Falkovich, V. Lebedev, Y. Liu, and V. Steinberg

Polymer molecules in a flow undergo a coil-stretch phase transition on an increase of the velocity gradients. Model-independent identification and characterization of the transition in a random flow has been lacking so far. Here we suggest to use the entropy of the extension statistics as a proper m...

[Phys. Rev. E 103, 033107] Published Wed Mar 17, 2021

Author(s): Davin Lunz

We consider a thin fluid film flowing down an inclined substrate subjected to localized external sources of momentum and heat flux that induce deformations of the fluid's free surface. This scenario is encountered in several industrial processes and of particular interest is the case where these def...

[Phys. Rev. E 103, 033105] Published Tue Mar 16, 2021

Author(s): Alexandros Tsimpoukis, Steryios Naris, and Dimitris Valougeorgis

The rarefied, oscillatory, pressure-driven binary gas mixture flow between parallel plates is computationally investigated in terms of the mixture molar fraction and molecular mass ratio of the species, in a wide range of gas rarefaction and oscillation frequency. Modeling is based on the McCormack ...

[Phys. Rev. E 103, 033103] Published Mon Mar 15, 2021

Author(s): Zixing Liu, Guangyao Xu, Zhengyang Ni, Xizhou Chen, Xiasheng Guo, Juan Tu, and Dong Zhang

Acousotophoretic particle separations in counterpropagating surface acoustic wave (SAW) fields, e.g., standing SAWs (SSAWs), phase modulated SSAWs, tilted angle SSAWs, and partial standing SAWs, have proven successful. But there still lacks analytical tools for predicting the particle trajectory and...

[Phys. Rev. E 103, 033104] Published Mon Mar 15, 2021

Author(s): Kevin Ha, Jean-Marc Chomaz, and Sabine Ortiz

For the classical problem of the rotation of a solid, we show a somehow surprising behavior involving large transient growth of perturbation energy that occurs when the moment of inertia associated to the unstable axis approaches the moment of inertia of one of the two stable axes. In that case, sma...

[Phys. Rev. E 103, 033102] Published Thu Mar 11, 2021

Author(s): Jorge Yáñez Escanciano, Mike Kuznetsov, and Fernando Veiga-López

The physical limits of the unconventional flame propagation regimes recently discovered [Veiga-Lopez et al., Phys. Rev. Lett. 124, 174501 (2020)] are analyzed. These regimes appear in combustible gaseous mixtures approaching the lean quenching limit of hydrogen-air flames in narrow gaps. They are c...

[Phys. Rev. E 103, 033101] Published Wed Mar 03, 2021

Author(s): Ji Zhang, Mauro Chinappi, and Luca Biferale

The motion of microswimmers in complex flows is ruled by the interplay between swimmer propulsion and the dynamics induced by the fluid velocity field. Here we study the motion of a chiral microswimmer whose propulsion is provided by the spinning of a helical tail with respect to its body in a simpl...

[Phys. Rev. E 103, 023109] Published Fri Feb 26, 2021

Author(s): Ji-Xiang Wang, Patrick Birbarah, Donald Docimo, Tianyu Yang, Andrew G. Alleyne, and Nenad Miljkovic

Analogous to an electrical rectifier, a thermal rectifier (TR) can ensure that heat flows in a preferential direction. In this paper, thermal transport nonlinearity is achieved through the development of a phase-change based TR comprising an enclosed vapor chamber having separated nanostructured cop...

[Phys. Rev. E 103, 023110] Published Fri Feb 26, 2021

Author(s): Riccardo Vesipa, Eleonora Paissoni, Costantino Manes, and Luca Ridolfi

Several studies have investigated the dynamics of a single spherical bubble at rest under a nonstationary pressure forcing. However, attention has almost always been focused on periodic pressure oscillations, neglecting the case of stochastic forcing. This fact is quite surprising, as random pressur...

[Phys. Rev. E 103, 023108] Published Tue Feb 23, 2021