Latest papers in fluid mechanics

Network community-based model reduction for vortical flows

Physical Review E - Mon, 06/11/2018 - 11:00

Author(s): Muralikrishnan Gopalakrishnan Meena, Aditya G. Nair, and Kunihiko Taira

A network community-based reduced-order model is developed to capture key interactions among coherent structures in high-dimensional unsteady vortical flows. The present approach is data-inspired and founded on network-theoretic techniques to identify important vortical communities that are comprise...


[Phys. Rev. E 97, 063103] Published Mon Jun 11, 2018

Viscoelastic fluid-structure interactions between a flexible cylinder and wormlike micelle solution

Physical Review Fluids - Mon, 06/11/2018 - 11:00

Author(s): Anita A. Dey, Yahya Modarres-Sadeghi, and Jonathan P. Rothstein

Elastic flow instabilities in the wake of a flexible cylinder can drive the motion of the cylinder, resulting in 1D and 2D oscillations. The time variation of the flow field and the state of stress in the fluid are shown using particle image tracking and flow-induced birefringence images.


[Phys. Rev. Fluids 3, 063301] Published Mon Jun 11, 2018

Manipulation of viscous fingering in a radially tapered cell geometry

Physical Review E - Fri, 06/08/2018 - 11:00

Author(s): Grégoire Bongrand and Peichun Amy Tsai

When a more mobile fluid displaces another immiscible one in a porous medium, viscous fingering propagates with a partial sweep, which hinders oil recovery and soil remedy. We experimentally investigate the feasibility of tuning such fingering propagation in a nonuniform narrow passage with a radial...


[Phys. Rev. E 97, 061101(R)] Published Fri Jun 08, 2018

Internal waves in sheared flows: Lower bound of the vorticity growth and propagation discontinuities in the parameter space

Physical Review E - Fri, 06/08/2018 - 11:00

Author(s): Federico Fraternale, Loris Domenicale, Gigliola Staffilani, and Daniela Tordella

This study provides sufficient conditions for the temporal monotonic decay of enstrophy for two-dimensional perturbations traveling in the incompressible, viscous, plane Poiseuille, and Couette flows. Extension of Synge's procedure [J. L. Synge, Proc. Fifth Int. Congress Appl. Mech. 2, 326 (1938); S...


[Phys. Rev. E 97, 063102] Published Fri Jun 08, 2018

Rheology of dense granular flows in two dimensions: Comparison of fully two-dimensional flows to unidirectional shear flow

Physical Review Fluids - Fri, 06/08/2018 - 11:00

Author(s): Ashish Bhateja and Devang V. Khakhar

Numerical simulations of dense granular flows in three different planar geometries find that the μ-I scaling for the local viscosity is found to be valid for each geometry, but the data for the three geometries do not collapse to a single curve.


[Phys. Rev. Fluids 3, 062301(R)] Published Fri Jun 08, 2018

Hydrodynamic bifurcation in electro-osmotically driven periodic flows

Physical Review Fluids - Fri, 06/08/2018 - 11:00

Author(s): Alexander Morozov, Davide Marenduzzo, and Ronald G. Larson

In this paper, we report an inertial instability that occurs in electro-osmotically driven channel flows. We assume that the charge motion under the influence of an externally applied electric field is confined to a small vicinity of the channel walls that, effectively, drives a bulk flow through a ...


[Phys. Rev. Fluids 3, 063702] Published Fri Jun 08, 2018

Influence of a thin compressible insoluble liquid film on the eddy currents generated by interacting surface waves

Physical Review Fluids - Fri, 06/08/2018 - 11:00

Author(s): Vladimir M. Parfenyev and Sergey S. Vergeles

Crossed surface waves generate eddy currents near the fluid surface owing to hydrodynamic nonlinearity. We studied how these currents penetrate into the fluid bulk and showed that a thin compressible insoluble liquid film presented on the fluid surface increases their intensity.


[Phys. Rev. Fluids 3, 064702] Published Fri Jun 08, 2018

Observation of the pressure effect in simulations of droplets splashing on a dry surface

Physical Review Fluids - Thu, 06/07/2018 - 11:00

Author(s): A. M. P. Boelens, A. Latka, and J. J. de Pablo

At atmospheric pressure, a droplet impacting on a surface produces a splash. Reducing the ambient pressure suppresses this splash. The pressure effect is not well understood and this is the first study to present an in-depth comparison between various theoretical splashing models and simulations.


[Phys. Rev. Fluids 3, 063602] Published Thu Jun 07, 2018

Electrohydrodynamic ionic wind, force field, and ionic mobility in a positive dc wire-to-cylinders corona discharge in air

Physical Review Fluids - Thu, 06/07/2018 - 11:00

Author(s): Nicolas Monrolin, Olivier Praud, and Franck Plouraboué

Particle image velocimetry of ionic wind produced by a positive dc corona in air is used to evaluate lift force, and results are consistent with a general theoretical expression previously found for net momentum transfer. Momentum transfer efficiency is found to be sensitive to the electrode aerodynamic wake and the electric field orientation.


[Phys. Rev. Fluids 3, 063701] Published Thu Jun 07, 2018

Numerical investigation of homogeneous cavitation nucleation in a microchannel

Physical Review Fluids - Thu, 06/07/2018 - 11:00

Author(s): Xiuxiu Lyu, Shucheng Pan, Xiangyu Hu, and Nikolaus A. Adams

With the Euler-Lagrangian coupled method we simulate homogeneous nucleation cavitation induced by shock reflection in a microchannel. Nucleation is found to occur in three stages: energy deposition, generation, and growth. Initial generation time is not found to depend strongly on shock intensity.


[Phys. Rev. Fluids 3, 064303] Published Thu Jun 07, 2018

Electrochemical wall shear rate microscopy of collapsing bubbles

Physical Review Fluids - Wed, 06/06/2018 - 11:00

Author(s): Fabian Reuter and Robert Mettin

A high-speed method for time-resolved measurements of wall shear rates providing microscopic resolution is presented. The wall shear rates produced by a single, collapsing cavitation bubble are studied.


[Phys. Rev. Fluids 3, 063601] Published Wed Jun 06, 2018

Examination of propeller sound production using large eddy simulation

Physical Review Fluids - Wed, 06/06/2018 - 11:00

Author(s): Jacob Keller, Praveen Kumar, and Krishnan Mahesh

Results of a high-fidelity large eddy simulation are used to compute the far-field sound that results from the unsteady loading of a propeller operating at design condition. High levels of unsteadiness at the blade tip account for the majority of far-field sound.


[Phys. Rev. Fluids 3, 064601] Published Wed Jun 06, 2018

Onset of chaos in helical vortex breakdown at low Reynolds number

Physical Review Fluids - Wed, 06/06/2018 - 11:00

Author(s): S. Pasche, F. Avellan, and F. Gallaire

The dynamics of the helical vortex breakdown has revealed a Ruelle-Takens-Newhouse route to chaos coming from the nonlinear interactions of pure hydrodynamic modes. Global stability analysis, Fourier series decomposition, and time series analysis have been used to shed light on the dynamical states.


[Phys. Rev. Fluids 3, 064701] Published Wed Jun 06, 2018

Edge effects on the fluttering characteristics of freely falling planar particles

Physical Review Fluids - Tue, 06/05/2018 - 11:00

Author(s): Luis Blay Esteban, John Shrimpton, and Bharathram Ganapathisubramani

Trajectories of N-sided polygons falling in quiescent media are used to measure the edge effect on the descent. A new length scale is proposed to estimate the equivalent dimensionless numbers. This allows use of the original phase diagram for disks and reconciles the effects of particle shape.


[Phys. Rev. Fluids 3, 064302] Published Tue Jun 05, 2018

Experimental investigation of the Peregrine Breather of gravity waves on finite water depth

Physical Review Fluids - Mon, 06/04/2018 - 11:00

Author(s): G. Dong, B. Liao, Y. Ma, and M. Perlin

A series of laboratory experiments were performed to study the Peregrine Breather evolution in a wave flume of finite depth and deep water. The experimental results are compared with computations based on both the nonlinear Schrödinger equation and the Dysthe equation, both with a dissipation term.


[Phys. Rev. Fluids 3, 064801] Published Mon Jun 04, 2018

Contact line friction of electrowetting actuated viscous droplets

Physical Review E - Fri, 06/01/2018 - 11:00

Author(s): Quoc Vo and Tuan Tran

Droplets on a surface immersed in oil are made to spread and retract by switching on and off a potential difference between the droplets and the surface. The authors find that the contact line friction depends on the viscosities of the droplet and the surrounding oil and that it does not depend significantly on the driving force or the direction of motion.


[Phys. Rev. E 97, 063101] Published Fri Jun 01, 2018

Inhomogeneous growth of fluctuations of concentration of inertial particles in channel turbulence

Physical Review Fluids - Fri, 06/01/2018 - 11:00

Author(s): Itzhak Fouxon, Lukas Schmidt, Peter Ditlevsen, Maarten van Reeuwijk, and Markus Holzner

We investigate how an initially uniform distribution of small inertial particles evolves due to transport by turbulent channel flow. Concentration fluctuations grow as particles approach a multifractal attractor with strong dependence on the distance to the wall which can be faster than exponential.


[Phys. Rev. Fluids 3, 064301] Published Fri Jun 01, 2018

Permeability of solid foam: Effect of pore connections

Physical Review E - Thu, 05/31/2018 - 11:00

Author(s): V. Langlois, V. H. Trinh, C. Lusso, C. Perrot, X. Chateau, Y. Khidas, and O. Pitois

In this paper, we study how the permeability of solid foam is modified by the presence of membranes that close partially or totally the cell windows connecting neighboring pores. The finite element method (FEM) simulations computing the Stokes problem are performed at both pore and macroscopic scale...


[Phys. Rev. E 97, 053111] Published Thu May 31, 2018

Single-bubble and multibubble cavitation in water triggered by laser-driven focusing shock waves

Physical Review E - Thu, 05/31/2018 - 11:00

Author(s): D. Veysset, U. Gutiérrez-Hernández, L. Dresselhaus-Cooper, F. De Colle, S. Kooi, K. A. Nelson, P. A. Quinto-Su, and T. Pezeril

In this study a single laser pulse spatially shaped into a ring is focused into a thin water layer, creating an annular cavitation bubble and cylindrical shock waves: an outer shock that diverges away from the excitation laser ring and an inner shock that focuses towards the center. A few nanosecond...


[Phys. Rev. E 97, 053112] Published Thu May 31, 2018

Meshfree and efficient modeling of swimming cells

Physical Review Fluids - Thu, 05/31/2018 - 11:00

Author(s): Meurig T. Gallagher and David J. Smith

We develop a tool for simulating three-dimensional locomotion in Stokes flow with highly resolved flow and swimming trajectories for multiple swimmers in the presence of surfaces. Key features include modularity, scalability, ease of implementation, and no need for mesh generation.


[Phys. Rev. Fluids 3, 053101] Published Thu May 31, 2018

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