Physical Review E
Author(s): G. Boffetta, M. Magnani, and S. Musacchio
The dynamics of Rayleigh-Taylor turbulence convection in the presence of an alternating, time-periodic acceleration is studied by means of extensive direct numerical simulations of the Boussinesq equations. Within this framework, we discover a mechanism of relaminarization of turbulence: the alterna...
[Phys. Rev. E 99, 033110] Published Mon Mar 11, 2019
Pore network model for permeability characterization of three-dimensionally-printed porous materials for passive microfluidics
Author(s): Agnese Piovesan, Clement Achille, Rob Ameloot, Bart Nicolai, and Pieter Verboven
Stand-alone and portable lab-on-chips (LOC) can be obtained by exploiting capillary flow in porous media. Polymethylmethacrylate (PMMA) platforms obtained through powder-based three-dimensional (3D) printing are appropriate for capillarity-driven LOCs. However, fluid flow in such platforms needs to ...
[Phys. Rev. E 99, 033107] Published Thu Mar 07, 2019
Anomalous transport dependence on Péclet number, porous medium heterogeneity, and a temporally varying velocity field
Author(s): Alon Nissan and Brian Berkowitz
We investigate the effects of the Péclet number (Pe) on transport of an inert chemical tracer in heterogeneous porous media. We simulate fluid flow and transport through two-dimensional pore-scale matrices with varying structural complexity. With increasing Pe, the anomalous nature of the transport ...
[Phys. Rev. E 99, 033108] Published Thu Mar 07, 2019
Author(s): Lu Qiu, Swapnil Dubey, Fook Hoong Choo, and Fei Duan
Unlike the traditionally reported Leidenfrost droplet which only floats on a thin film of vapor, we observe a prominent jump of the impinged droplets in the transition from the contact boiling to the Leidenfrost state. The vapor generation between the droplet and the substrate is vigorous enough to ...
[Phys. Rev. E 99, 033106] Published Tue Mar 05, 2019
Author(s): S. I. Blinnikov, R. I. Ilkaev, M. A. Mochalov, A. L. Mikhailov, I. L. Iosilevskiy, A. V. Yudin, S. I. Glazyrin, A. A. Golubev, V. K. Gryaznov, and S. V. Fortova
We draw attention to recent high-explosive (HE) experiments which provide compression of macroscopic amount of matter to high, even record, values of pressure in comparison with other HE experiments. The observed bounce after the compression corresponds to processes in core-collapse supernova explos...
[Phys. Rev. E 99, 033102] Published Mon Mar 04, 2019
Convective flow in the presence of a small obstacle: Symmetry breaking, attractors, hysteresis, and information
Author(s): S. J. Bartlett and Y. L. Yung
This work explores the stability and hysteresis effects that occur when a small sink of momentum is introduced into a heat-driven, two-dimensional convective flow. As per standard fluid mechanical intuition, the system minimizes work generation and dissipation when one component of momentum is extra...
[Phys. Rev. E 99, 033103] Published Mon Mar 04, 2019
Author(s): G. B. Apolinário, L. Moriconi, and R. M. Pereira
We study the onset of intermittency in stochastic Burgers hydrodynamics, as characterized by the statistical behavior of negative velocity gradient fluctuations. The analysis is based on the response functional formalism, where specific velocity configurations—the viscous instantons—are assumed to p...
[Phys. Rev. E 99, 033104] Published Mon Mar 04, 2019
Wavelength selection of vortex ripples in an oscillating cylinder: The effect of curvature and background rotation
Author(s): M. Duran-Matute, M. D. van Gorp, and G. J. F. van Heijst
We present results of laboratory experiments on the formation, evolution, and wavelength selection of vortex ripples. These ripples formed on a sediment bed at the bottom of a water-filled oscillating cylindrical tank mounted on top of a rotating table. The table is made to oscillate sinusoidally in...
[Phys. Rev. E 99, 033105] Published Mon Mar 04, 2019
Author(s): Vaseem A. Shaik and Arezoo M. Ardekani
In this work we analyze the velocity of a swimming sheet near a plane surfactant-laden interface by assuming the Reynolds number and the sheet's deformation to be small. We observe a nonmonotonic dependence of the sheet's velocity on the Marangoni number (Ma) and the surface Péclet number (Pes). For...
[Phys. Rev. E 99, 033101] Published Fri Mar 01, 2019
Author(s): R. M. Velasco and F. J. Uribe
In this work we present a phenomenological model to look for a better understanding of the shock-wave structure in dilute monatomic gases. The model is based on the principles of linear irreversible thermodynamics, where we have been aware of the flow anisotropy caused by the shock-wave propagation....
[Phys. Rev. E 99, 023114] Published Wed Feb 27, 2019
Author(s): Isabel Mercader, Oriol Batiste, Arantxa Alonso, and Edgar Knobloch
We analyze the effect of a small inclination on the well-studied problem of two-dimensional binary fluid convection in a horizontally extended closed rectangular box with a negative separation ratio, heated from below. The horizontal component of gravity generates a shear flow that replaces the moti...
[Phys. Rev. E 99, 023113] Published Tue Feb 26, 2019
Exact, approximate, and hybrid treatments of viscous Rayleigh-Taylor and Richtmyer-Meshkov instabilities
Author(s): Karnig O. Mikaelian
We consider Rayleigh-Taylor and Richtmyer-Meshkov instabilities at the interface between two fluids, one or both of which may be viscous. We derive exact analytic expressions for the amplitude η(t) in the linear regime when only one of the fluids is viscous. The more general case is solved numerical...
[Phys. Rev. E 99, 023112] Published Mon Feb 25, 2019