Physical Review Fluids

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Recent articles in Physical Review Fluids
Updated: 18 hours 12 min ago

Energy transport due to pressure diffusion enhanced by helicity and system rotation in inhomogeneous turbulence

Mon, 12/03/2018 - 10:00

Author(s): Kazuhiro Inagaki and Fujihiro Hamba

It is known that turbulent energy is rapidly transferred in the direction of the rotation axis in a rotating system, in comparison with the nonrotating case. A new turbulence model of the energy flux predicting this phenomenon is proposed and discussed in terms of turbulent helicity.

[Phys. Rev. Fluids 3, 124601] Published Mon Dec 03, 2018

Universal scaling law in frictional non-Brownian suspensions

Fri, 11/30/2018 - 10:00

Author(s): Frédéric Blanc, Enzo D'Ambrosio, Laurent Lobry, François Peters, and Elisabeth Lemaire

Suspensions made of either faceted or spherical particles behave in quite different ways. However, experiments show that it is possible to unify their behavior by considering the contact contribution to the viscosity that is evaluated through shear reversal experiments.

[Phys. Rev. Fluids 3, 114303] Published Fri Nov 30, 2018

Mass entrainment-based model for separating flows

Fri, 11/30/2018 - 10:00

Author(s): F. Stella, N. Mazellier, P. Joseph, and A. Kourta

The recirculation flow bounding a forced separating and reattaching shear layer is modeled. Experimental results emphasize that mass entrainment is a key parameter on which the parameters of the model scale. It is shown that an inexpensive and easily deployable sensor can be used to estimate the backflow.

[Phys. Rev. Fluids 3, 114702] Published Fri Nov 30, 2018

Versatile reduced-order model of leading-edge vortices on rotary wings

Fri, 11/30/2018 - 10:00

Author(s): D. Chen, D. Kolomenskiy, R. Onishi, and H. Liu

An analytical model is proposed for the strength and position of the Leading Edge Vortex on a revolving wing at an arbitrary angle of attack. Predictions are compared with experiments and numerical solutions.

[Phys. Rev. Fluids 3, 114703] Published Fri Nov 30, 2018

Multiple states and heat transfer in two-dimensional tilted convection with large aspect ratios

Thu, 11/29/2018 - 10:00

Author(s): Qi Wang, Zhen-Hua Wan, Rui Yan, and De-Jun Sun

Multiple stable states exist for two-dimensional tilted convection with large aspect ratios (Γ≥2). The Nusselt number generally decreases monotonically with increasing tilt angle for large Γ cases with Γ≥8.

[Phys. Rev. Fluids 3, 113503] Published Thu Nov 29, 2018

Conditionally averaged flow topology about a critical point pair in the skin friction field of pipe flows using direct numerical simulations

Wed, 11/28/2018 - 10:00

Author(s): R. C. Chin, J. P. Monty, M. S. Chong, and I. Marusic

The flow topology in the vicinity of critical points in a pipe flow reveals turbulence motions resembling hairpin-like vortical structures. Three-dimensional U separation is found to be closely associated with critical points that could form a simple model for wall turbulence.

[Phys. Rev. Fluids 3, 114607] Published Wed Nov 28, 2018

Phenomenology of bubble-collapse-driven penetration of biomaterial-surrogate liquid-liquid interfaces

Tue, 11/27/2018 - 10:00

Author(s): Shucheng Pan, Stefan Adami, Xiangyu Hu, and Nikolaus A. Adams

Bubble-collapse-driven penetration of liquid-liquid interfaces exhibits two scaling ranges of penetration depth vs time. Detailed numerical simulations show that size and evolution of generated interface perforations depend on viscosity, shock strength, and single- or multiple-bubble configurations.

[Phys. Rev. Fluids 3, 114005] Published Tue Nov 27, 2018

Classical impulsive model for dissociation of diatomic molecules in direct simulation Monte Carlo

Mon, 11/26/2018 - 10:00

Author(s): Han Luo, Israel B. Sebastião, Alina A. Alexeenko, and Sergey O. Macheret

This paper presents a new implementation of the Macheret-Fridman dissociation model for the direct simulation Monte Carlo method to model thermal nonequilibrium dissociation reactions. We find good agreement with recent quasi-classical trajectory calculations and recent experimental results.

[Phys. Rev. Fluids 3, 113401] Published Mon Nov 26, 2018

Simulation of surfactant-mediated tipstreaming in a flow-focusing geometry

Mon, 11/26/2018 - 10:00

Author(s): Jacek K. Wrobel, Michael R. Booty, Michael Siegel, and Qiming Wang

A surfactant coated drop is drawn through an aperture by a converging flow. Under suitable conditions that have also been investigated in a series of independently led experiments, the drop tip emits a thin tipstreaming thread that later breaks up into near-monodisperse droplets.

[Phys. Rev. Fluids 3, 114003] Published Mon Nov 26, 2018

Evolution of a shocked multimode interface with sharp corners

Mon, 11/26/2018 - 10:00

Author(s): Xu Guo, Juchun Ding, Xisheng Luo, and Zhigang Zhai

Evolution of a shocked inverse-chevron interface is studied experimentally, and the effect of vertex angle is highlighted. A new nonlinear model is constructed and provides a better prediction of interface growth than previous models.

[Phys. Rev. Fluids 3, 114004] Published Mon Nov 26, 2018

Steady two-dimensional free-surface flow over semi-infinite and finite-length corrugations in an open channel

Mon, 11/26/2018 - 10:00

Author(s): Jack S. Keeler, Benjamin J. Binder, and Mark G. Blyth

Steady free-surface flow over a semi-infinite and finite corrugated bottom is considered. It is demonstrated that by varying the Froude number a wide range of nontrivial solutions can be constructed, including generalized hydraulic falls, table-top solitons, and perturbed solitary waves.

[Phys. Rev. Fluids 3, 114804] Published Mon Nov 26, 2018

Experimental adventures in variable-density mixing

Wed, 11/21/2018 - 10:00

Author(s): Kathy Prestridge

Variable-density has important physical effects on turbulence, including driving mixing from small to large scales. Many compressible and variable-density flow applications cannot be simulated directly. Recent experimental measurements have implications for modeling and underresolved simulations.

[Phys. Rev. Fluids 3, 110501] Published Wed Nov 21, 2018

Particle-induced viscous fingering: Review and outlook

Wed, 11/21/2018 - 10:00

Author(s): Rui Luo, Yun Chen, and Sungyon Lee

When a mixture of noncolloidal particles and oil displaces air inside a Hele-Shaw cell, particles accumulate on the interface and cause fingering by generating an unstable viscosity gradient inside the suspension. A review and new data of the fingering onset and evolution are presented.

[Phys. Rev. Fluids 3, 110502] Published Wed Nov 21, 2018

Role of singularities in hydrodynamics

Wed, 11/21/2018 - 10:00

Author(s): J. Eggers

The image of a turbulent jet reveals complex spatial patterns, which result from the decay of turbulent eddies into smaller and smaller structures. Here we lay out a road map to describe such patterns as a result of singularities which possess both a nontrivial spatial structure, and exhibit instability as they progress toward smaller and smaller scales.

[Phys. Rev. Fluids 3, 110503] Published Wed Nov 21, 2018

Bubble puzzles: From fundamentals to applications

Wed, 11/21/2018 - 10:00

Author(s): Detlef Lohse

This paper sketches my personal scientific bubble journey, starting with single-bubble sonoluminescence, continuing with sound emission and scattering of bubbles, cavitation, snapping shrimp, impact events, air entrainment, and surface micro- and nanobubbles, and finally arriving at effective force models for bubbles and dispersed bubbly two-phase flow.

[Phys. Rev. Fluids 3, 110504] Published Wed Nov 21, 2018

Liquid fraction profile in a liquid foam under an applied voltage

Wed, 11/21/2018 - 10:00

Author(s): Anne-Laure Biance and Oriane Bonhomme

Liquid transport in a dry foam, a deformable porous material, in the presence of an applied electric field, is computed in the limits of rigid and mobile interfaces. The evolution of the liquid distribution is diffusive-like and significantly affected by the hydrodynamic boundary conditions.

[Phys. Rev. Fluids 3, 110505] Published Wed Nov 21, 2018

Revealing hidden information with quadratic products of acoustic field amplitudes

Wed, 11/21/2018 - 10:00

Author(s): David R. Dowling

Since the development of propagating-wave-based remote sensing more than a century ago, signal analysis has been limited to in-band recorded frequencies. However, this limitation is artificial. A new discovery from the realm of sonar shows that remote sensing is possible at out-of-band frequencies.

[Phys. Rev. Fluids 3, 110506] Published Wed Nov 21, 2018

Direct numerical simulations of premixed and stratified flame propagation in turbulent channel flow

Wed, 11/21/2018 - 10:00

Author(s): Andrea Gruber, Edward S. Richardson, Konduri Aditya, and Jacqueline H. Chen

Flashback is a key operational and safety issue for modern low-emission burners. With direct numerical simulations we study upstream flame movement through the turbulent flow within a channel and address the marked change in flashback behavior when the fuel and oxidant mixture is not homogeneous.

[Phys. Rev. Fluids 3, 110507] Published Wed Nov 21, 2018

Lubricated-to-frictional shear thickening scenario in dense suspensions

Wed, 11/21/2018 - 10:00

Author(s): Jeffrey F. Morris

A scenario in which shear thickening results from a transition of interactions between suspended particles from lubricated to frictional (LF) with increasing stress is described, with a presentation of primary results and a perspective on outstanding questions which are raised by the LF mechanism.

[Phys. Rev. Fluids 3, 110508] Published Wed Nov 21, 2018

Sensitivity analysis of thermoacoustic instability with adjoint Helmholtz solvers

Wed, 11/21/2018 - 10:00

Author(s): Matthew P. Juniper

The power density in a rocket engine is 50 GW/m3. If flame oscillations lock into the acoustic modes of the chamber, the resultant noise can blow up the engine. This paper explains pedagogically, with example code, how best to use adjoint methods to passively control this thermoacoustic instability.

[Phys. Rev. Fluids 3, 110509] Published Wed Nov 21, 2018