Latest papers in fluid mechanics

Drag enhancement and drag reduction in viscoelastic flow

Physical Review Fluids - Mon, 10/15/2018 - 11:00

Author(s): Atul Varshney and Victor Steinberg

The effect of inertia on the stability of viscoelastic flow is investigated. Three regions in the stability diagram are identified based on fluid elasticity, and a regime of flow relaminarization is discovered for high elasticity at Re up to 10, different from known turbulent drag reduction.


[Phys. Rev. Fluids 3, 103302] Published Mon Oct 15, 2018

Flow measurements in microporous media using micro-particle image velocimetry

Physical Review Fluids - Mon, 10/15/2018 - 11:00

Author(s): Xianke Lu, Yuyuan Zhao, and David J. C. Dennis

An experimental study identifies four regimes of flow through complex microporous materials by measuring the velocity field at the pore scale. As Re is varied different pathways become effective at transporting fluid through the porous media, changing the effective permeability of the material.


[Phys. Rev. Fluids 3, 104202] Published Mon Oct 15, 2018

Universal friction law at granular solid-gas transition explains scaling of sediment transport load with excess fluid shear stress

Physical Review Fluids - Mon, 10/15/2018 - 11:00

Author(s): Thomas Pähtz and Orencio Durán

We find that the granular friction coefficient and other local quantities controlling the scaling behavior of sediment transport vary only little across all simulated transport conditions when evaluated at the interface between the solid-like granular bed and the gas-like transport layer.


[Phys. Rev. Fluids 3, 104302] Published Mon Oct 15, 2018

Erosion of unconsolidated beds by turbidity currents

Physical Review Fluids - Mon, 10/15/2018 - 11:00

Author(s): Thomas C. Halsey

Underwater turbidity currents erode and suspend granular material from underlying beds; the kinetics of this process controls overall flow dynamics. A study confirms a decades-old conjecture by Bagnold that the erosion process is driven by a balance between fluid and grain effects.


[Phys. Rev. Fluids 3, 104303] Published Mon Oct 15, 2018

Onset criteria for freely decaying isotropic turbulence

Physical Review Fluids - Mon, 10/15/2018 - 11:00

Author(s): S. R. Yoffe and W. D. McComb

A numerical simulation of freely decaying turbulence shows that the iconic curve of dimensionless dissipation against Reynolds number depends quite strongly on the choice of time at which the turbulence is assumed to have evolved from the arbitrary initial conditions.


[Phys. Rev. Fluids 3, 104605] Published Mon Oct 15, 2018

Trapping of plasma enabled by pycnoclinic acoustic force

Physical Review E - Fri, 10/12/2018 - 11:00

Author(s): John P. Koulakis, Seth Pree, Alexander L. F. Thornton, and Seth Putterman

Sound can hold partially ionized sulfur at the center of a spherical bulb. We use the sulfur plasma itself to drive a 180 dB re 20 μPa sound wave by periodically heating it with microwave pulses at a frequency that matches the lowest order, spherically symmetric, acoustic resonance of the bulb. To c...


[Phys. Rev. E 98, 043103] Published Fri Oct 12, 2018

Size and shape affect swimming of a triangular bead-spring microswimmer

Physical Review E - Fri, 10/12/2018 - 11:00

Author(s): Mohd Suhail Rizvi, Alexander Farutin, and Chaouqi Misbah

We investigate analytically the transport characteristics of the triangular bead-spring microswimmer and its dependence on the sizes of the beads as well as on the relative bead configurations. The microswimmer is composed of three beads connected by linear springs in an isosceles triangular arrange...


[Phys. Rev. E 98, 043104] Published Fri Oct 12, 2018

Mach number effect on the instability of a planar interface subjected to a rippled shock

Physical Review E - Fri, 10/12/2018 - 11:00

Author(s): Wenbin Zhang, Qiang Wu, Liyong Zou, Xianxu Zheng, Xinzhu Li, Xisheng Luo, and Juchun Ding

The Richtmyer-Meshkov (RM) instability of a planar interface (N2−SF6) subjected to a sinusoidal rippled shock, as the variant of a sinusoidal interface impinged by a planar shock, is investigated through high-order compressible multicomponent hydrodynamic simulations. The rippled shock is generated ...


[Phys. Rev. E 98, 043105] Published Fri Oct 12, 2018

Suppression of von Kármán vortex streets past porous rectangular cylinders

Physical Review Fluids - Fri, 10/12/2018 - 11:00

Author(s): P. G. Ledda, L. Siconolfi, F. Viola, F. Gallaire, and S. Camarri

The effect of the porosity and permeability on the wakes of porous rectangular cylinders is numerically studied using linear stability analyses. We show that the flow is progressively stabilized when obstacles of increased permeability are considered, up to the suppression of the vortex shedding.


[Phys. Rev. Fluids 3, 103901] Published Fri Oct 12, 2018

Time-dependent active microrheology in dilute colloidal suspensions

Physical Review Fluids - Thu, 10/11/2018 - 11:00

Author(s): Sebastian Leitmann, Suvendu Mandal, Matthias Fuchs, Antonio M. Puertas, and Thomas Franosch

An exact analytic solution is derived for the dynamic response of a probe particle in a dilute colloidal suspension exposed to a strong step force.


[Phys. Rev. Fluids 3, 103301] Published Thu Oct 11, 2018

Optimal cell transport in straight channels and networks

Physical Review Fluids - Thu, 10/11/2018 - 11:00

Author(s): Alexander Farutin, Zaiyi Shen, Gael Prado, Vassanti Audemar, Hamid Ez-Zahraouy, Abdelilah Benyoussef, Benoit Polack, Jens Harting, Petia M. Vlahovska, Thomas Podgorski, Gwennou Coupier, and Chaouqi Misbah

The optimization of the transport of suspended deformable particles in channels and networks is studied. The complexity of global optimization at the level of an entire network with channels of different lengths and diameters is highlighted, with a specific focus on blood circulation.


[Phys. Rev. Fluids 3, 103603] Published Thu Oct 11, 2018

Quasistatic fluid-fluid displacement in porous media: Invasion-percolation through a wetting transition

Physical Review Fluids - Thu, 10/11/2018 - 11:00

Author(s): Bauyrzhan K. Primkulov, Stephen Talman, Keivan Khaleghi, Alireza Rangriz Shokri, Rick Chalaturnyk, Benzhong Zhao, Christopher W. MacMinn, and Ruben Juanes

We introduce an invasion-percolation model which reproduces quasistatic fluid-fluid displacement patterns in porous media under different wettability conditions. Depending on wettability, the fluid front advances through capillary invasion, cooperative filling, or corner flow.


[Phys. Rev. Fluids 3, 104001] Published Thu Oct 11, 2018

Parameter estimation for complex thermal-fluid flows using approximate Bayesian computation

Physical Review Fluids - Thu, 10/11/2018 - 11:00

Author(s): Jason D. Christopher, Nicholas T. Wimer, Caelan Lapointe, Torrey R. S. Hayden, Ian Grooms, Gregory B. Rieker, and Peter E. Hamlington

Approximate Bayesian Computation (ABC) is used to estimate unknown physical parameters in complex thermal-fluid flows.


[Phys. Rev. Fluids 3, 104602] Published Thu Oct 11, 2018

Permanence of large eddies in Richtmyer-Meshkov turbulence with a small Atwood number

Physical Review Fluids - Thu, 10/11/2018 - 11:00

Author(s): Olivier Soulard, Florian Guillois, Jérôme Griffond, Vladimir Sabelnikov, and Serge Simoëns

The existence of large scale invariants in a Richtmyer-Meshkov turbulent mixing zone with a small Atwood number is studied. The impact of these invariants on the self-similarity of the flow, on its anisotropy and mixing levels, is then discussed.


[Phys. Rev. Fluids 3, 104603] Published Thu Oct 11, 2018

Inferring flow parameters and turbulent configuration with physics-informed data assimilation and spectral nudging

Physical Review Fluids - Thu, 10/11/2018 - 11:00

Author(s): Patricio Clark Di Leoni, Andrea Mazzino, and Luca Biferale

A data assimilation technique called nudging is used to control the evolution of turbulence simulations. By studying the response of each simulation to the nudging, information on physical flow parameters is inferred from the data being assimilated.


[Phys. Rev. Fluids 3, 104604] Published Thu Oct 11, 2018

Three-dimensional steady and oscillatory flow in a double bifurcation airway model

Physical Review Fluids - Wed, 10/10/2018 - 11:00

Author(s): Sahar Jalal, Tristan Van de Moortele, Andras Nemes, Omid Amili, and Filippo Coletti

Using Magnetic Resonance Velocimetry, we investigate the steady expiratory and the oscillatory flow in a planar double bifurcation model with geometric proportions relevant to the respiratory human airways for a range of Reynolds (Re) and Womersley (Wo) numbers.


[Phys. Rev. Fluids 3, 103101] Published Wed Oct 10, 2018

Reynolds-number power-law scaling of differential molecular diffusion in turbulent nonpremixed combustion

Physical Review Fluids - Wed, 10/10/2018 - 11:00

Author(s): Chao Han and Haifeng Wang

A statistical analysis is conducted to provide support to a theoretical power-law scaling of the effect of differential molecular diffusion with respect to the Reynolds number in turbulent non-premixed combustion by using previously published direct number simulation data.


[Phys. Rev. Fluids 3, 103201] Published Wed Oct 10, 2018

Thermally modulated cross-stream migration of a surfactant-laden deformable drop in a Poiseuille flow

Physical Review Fluids - Wed, 10/10/2018 - 11:00

Author(s): Sayan Das and Suman Chakraborty

Shape deformation of a surfactant-laden droplet interacts uniquely with a given thermal field to alter its migration in the cross stream direction in response to an applied pressure gradient.


[Phys. Rev. Fluids 3, 103602] Published Wed Oct 10, 2018

Air-propelled, herringbone-textured platelets

Physical Review Fluids - Tue, 10/09/2018 - 11:00

Author(s): Hélène de Maleprade, Dan Soto, David Quéré, E. John Hinch, Tobias Baier, Maximilian T. Schür, and Steffen Hardt

A plate floating on a cushion of air blown through a porous substrate is set in motion when herringbone-shaped grooves redirect the airflow in a preferred direction, allowing contactless manipulation of objects.


[Phys. Rev. Fluids 3, 104101] Published Tue Oct 09, 2018

Influence of wettability on phase connectivity and electrical resistivity

Physical Review E - Mon, 10/08/2018 - 11:00

Author(s): Zhishang Liu, James E. McClure, and Ryan T. Armstrong

Experimental results have shown that resistivity index can deviate from Archie's law at low conductive phase saturation. Previous works have claimed that wettability and flow history are the two main factors causing this phenomenon. Herein, we investigate how the underlying fluid morphology influenc...


[Phys. Rev. E 98, 043102] Published Mon Oct 08, 2018

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