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Sep 2005

Volume 17, Issue 9, Articles (09xxxx)

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Introduction: 22nd Annual Gallery of Fluid Motion (Seattle, Washington, 2004)

James C. Hermanson

Phys. Fluids 17, 091101 (2005); http://dx.doi.org/10.1063/1.1942511 (1 page)

Online Publication Date: 26 August 2005

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Abstract Unavailable
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01.30.-y Physics literature and publications
47.10.-g General theory in fluid dynamics
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Wake of a low aspect ratio pitching plate

James H. J. Buchholz and Alexander J. Smits

Phys. Fluids 17, 091102 (2005); http://dx.doi.org/10.1063/1.1942512 (1 page) | Cited 4 times

Online Publication Date: 26 August 2005

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47.27.wb Turbulent wakes
47.32.C- Vortex dynamics
47.55.Hd Stratified flows
47.15.Fe Stability of laminar flows
47.40.-x Compressible flows; shock waves
47.27.T- Turbulent transport processes
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Visualization of a fish wake using tobacco mosaic virus

David L. Hu, Lucy Mendel, Brian Chan, Thomas Goreau, and John W. M. Bush

Phys. Fluids 17, 091103 (2005); http://dx.doi.org/10.1063/1.1942515 (1 page) | Cited 1 time

Online Publication Date: 26 August 2005

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Abstract Unavailable
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47.80.-v Instrumentation and measurement methods in fluid dynamics
47.27.wb Turbulent wakes
47.55.Kf Particle-laden flows
47.32.C- Vortex dynamics
FREE

Hydrogen bubble flow visualization of a self-oscillating cylinder vortex street “void”

Stuart Gilbert and Lorenz Sigurdson

Phys. Fluids 17, 091104 (2005); http://dx.doi.org/10.1063/1.1942516 (1 page) | Cited 1 time

Online Publication Date: 26 August 2005

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Abstract Unavailable
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47.55.D- Drops and bubbles
47.55.Kf Particle-laden flows
47.32.C- Vortex dynamics
47.35.-i Hydrodynamic waves
47.15.Fe Stability of laminar flows
47.60.-i Flow phenomena in quasi-one-dimensional systems
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Structure of unstable gaseous detonation waves

Matei I. Radulescu, Chung K. Law, and Gary J. Sharpe

Phys. Fluids 17, 091105 (2005); http://dx.doi.org/10.1063/1.1942517 (1 page)

Online Publication Date: 26 August 2005

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47.40.Ki Supersonic and hypersonic flows
47.70.Fw Chemically reactive flows
82.33.Vx Reactions in flames, combustion, and explosions
47.70.Nd Nonequilibrium gas dynamics
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Large-eddy simulation of Rayleigh–Taylor instability

William H. Cabot, Andrew W. Cook, Paul L. Miller, Daniel E. Laney, Mark C. Miller, and Henry R. Childs

Phys. Fluids 17, 091106 (2005); http://dx.doi.org/10.1063/1.1942519 (1 page) | Cited 1 time

Online Publication Date: 26 August 2005

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47.20.Lz Secondary instabilities
47.11.-j Computational methods in fluid dynamics
47.35.-i Hydrodynamic waves
47.60.-i Flow phenomena in quasi-one-dimensional systems
47.32.C- Vortex dynamics
47.27.-i Turbulent flows
02.70.Bf Finite-difference methods
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Settling and breakup of suspension drops

T. Bosse, L. Kleiser, J. Favre, and E. Meiburg

Phys. Fluids 17, 091107 (2005); http://dx.doi.org/10.1063/1.1942520 (1 page) | Cited 1 time

Online Publication Date: 26 August 2005

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Abstract Unavailable
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47.55.D- Drops and bubbles
47.55.Kf Particle-laden flows
47.11.-j Computational methods in fluid dynamics
47.35.-i Hydrodynamic waves
47.15.-x Laminar flows
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Vortex motion in the ocean: In situ visualization of jellyfish swimming and feeding flows

John O. Dabiri, Morteza Gharib, Sean P. Colin, and John H. Costello

Phys. Fluids 17, 091108 (2005); http://dx.doi.org/10.1063/1.1942521 (1 page) | Cited 2 times

Online Publication Date: 26 August 2005

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Abstract Unavailable
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47.32.C- Vortex dynamics
47.27.wb Turbulent wakes
47.55.Hd Stratified flows
47.60.-i Flow phenomena in quasi-one-dimensional systems
47.20.-k Flow instabilities
92.10.af Thermohaline convection
93.30.Rp Regional seas
93.30.Ge Europe
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Waves in a large free sphere of water on the International Space Station

Donald R. Pettit

Phys. Fluids 17, 091109 (2005); http://dx.doi.org/10.1063/1.1942522 (1 page)

Online Publication Date: 26 August 2005

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Abstract Unavailable
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47.35.-i Hydrodynamic waves
47.55.Kf Particle-laden flows
47.20.-k Flow instabilities
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Which way is up? A fluid dynamics riddle

Paul L. Miller, William H. Cabot, and Andrew W. Cook

Phys. Fluids 17, 091110 (2005); http://dx.doi.org/10.1063/1.1942513 (1 page) | Cited 1 time

Online Publication Date: 26 August 2005

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Abstract Unavailable
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47.20.Ma Interfacial instabilities (e.g., Rayleigh-Taylor)
47.11.-j Computational methods in fluid dynamics
47.55.Hd Stratified flows
47.35.-i Hydrodynamic waves
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Cavitating bubbles on patterned surfaces

Nicolas Bremond, Manish Arora, Claus-Dieter Ohl, and Detlef Lohse

Phys. Fluids 17, 091111 (2005); http://dx.doi.org/10.1063/1.1942514 (1 page) | Cited 4 times

Online Publication Date: 26 August 2005

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Abstract Unavailable
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47.55.dp Cavitation and boiling
47.55.D- Drops and bubbles
47.55.Kf Particle-laden flows
68.15.+e Liquid thin films
47.54.-r Pattern selection; pattern formation
FREE

Wake–shear layer interaction using a soap film tunnel

Humberto Bocanegra-Evans and James J. Allen

Phys. Fluids 17, 091112 (2005); http://dx.doi.org/10.1063/1.1942518 (1 page)

Online Publication Date: 26 August 2005

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Abstract Unavailable
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47.27.wb Turbulent wakes
47.20.Ft Instability of shear flows (e.g., Kelvin-Helmholtz)
47.35.-i Hydrodynamic waves
47.54.-r Pattern selection; pattern formation
47.32.C- Vortex dynamics
47.60.-i Flow phenomena in quasi-one-dimensional systems
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Clustering in high Re monodispersed bubbly flows

Bernardo Figueroa-Espinoza and Roberto Zenit

Phys. Fluids 17, 091701 (2005); http://dx.doi.org/10.1063/1.2055487 (4 pages) | Cited 8 times

Online Publication Date: 19 September 2005

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Experiments were conducted to determine the amount of clustering that occurs in bubbly flows for which the liquid motion can be described, with a certain degree of accuracy, using potential flow theory. A Hele-Shaw-type channel was used in which bubble overlap was avoided. Direct video image analysis was performed to calculate bubbles properties and identify cluster formation. Despite the significant wall influence of this configuration, it was found that the bubbles do form aggregates with a statistical horizontal tendency. The flow structure was also analyzed using the radial probability distribution, giving indications that support the clustering hypothesis.
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47.54.-r Pattern selection; pattern formation
47.55.D- Drops and bubbles
47.55.Kf Particle-laden flows
47.60.-i Flow phenomena in quasi-one-dimensional systems
02.50.-r Probability theory, stochastic processes, and statistics
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back to top Interfacial Flows

Soft lubrication: The elastohydrodynamics of nonconforming and conforming contacts

J. M. Skotheim and L. Mahadevan

Phys. Fluids 17, 092101 (2005); http://dx.doi.org/10.1063/1.1985467 (23 pages) | Cited 25 times

Online Publication Date: 2 September 2005

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We study the lubrication of fluid-immersed soft interfaces and show that elastic deformation couples tangential and normal forces and thus generates lift. We consider materials that deform easily, due to either geometry (e.g., a shell) or constitutive properties (e.g., a gel or a rubber), so that the effects of pressure and temperature on the fluid properties may be neglected. Four different system geometries are considered: a rigid cylinder moving parallel to a soft layer coating a rigid substrate; a soft cylinder moving parallel to a rigid substrate; a cylindrical shell moving parallel to a rigid substrate; and finally a cylindrical conforming journal bearing coated with a thin soft layer. In addition, for the particular case of a soft layer coating a rigid substrate, we consider both elastic and poroelastic material responses. For all these cases, we find the same generic behavior: there is an optimal combination of geometric and material parameters that maximizes the dimensionless normal force as a function of the softness parameter η = hydrodynamic pressure/elastic stiffness = surface deflection/gap thickness, which characterizes the fluid-induced deformation of the interface. The corresponding cases for a spherical slider are treated using scaling concepts.
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47.85.Dh Hydrodynamics, hydraulics, hydrostatics
47.56.+r Flows through porous media
46.55.+d Tribology and mechanical contacts
46.40.Jj Aeroelasticity and hydroelasticity
46.25.-y Static elasticity
back to top Viscous and Non-Newtonian Flows

Experimental observations of non-continuum effects in suspensions: Falling-ball versus towed-ball rheometry

Patrick T. Reardon, Alan L. Graham, James R. Abbott, and Howard Brenner

Phys. Fluids 17, 093101 (2005); http://dx.doi.org/10.1063/1.2035547 (7 pages) | Cited 1 time

Online Publication Date: 26 August 2005

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Viscosity is an intrinsic material property of Newtonian liquids, independent of the fluid’s strain rate and state of stress. Experiments performed on a test sphere traversing a homogeneous Newtonian fluid should establish the same viscosity whether by measuring the force on a test sphere moving at a constant velocity or by measuring the velocity of a test sphere animated by a constant force. Here we report on the results of experiments designed to compare constant force and constant velocity experiments for test spheres translating through suspensions of non-colloidal, neutrally buoyant spheres dispersed in viscous Newtonian fluids. Measurements were made of the apparent viscosity of a suspension relative to that of the pure fluid using either a settling ball animated by a constant gravitational force (ηrF) or a towed ball translating with a constant velocity (ηrV). The primary experimental parameters were the solids fraction (ϕ) in the suspension, and the ratio of the radius of the suspended spheres, as, to the radius of the test sphere, ab(λ = as/ab). As expected, the constant velocity and constant force experiments produced indistinguishable ηr’s for the homogeneous Newtonian fluids. However, over the range of suspension concentrations examined, ηrV was found to be significantly larger than ηrF. In all of the dilute and moderately concentrated suspensions, and in concentrated suspensions with very narrow size distributions, both ηrV and ηrF were found to be independent of the radius and the velocity of the test sphere. In concentrated suspensions possessing broad particle size distributions, both ηrV and ηrF were found to be shear thinning. However, the ratio ηrV/ηrF was observed to be independent of the shear rate. Even the most dilute suspensions examined proved to be non-Newtonian in the sense that ηrV/ηrF>1, with ηrV/ηrF observed to increase linearly with ϕ as the latter increased from 0.1 to 0.5. Over the range of our data, ηrV/ηrF decreases and approaches 1 as λ decreases for all ϕ.
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47.50.-d Non-Newtonian fluid flows
47.55.Kf Particle-laden flows
47.35.-i Hydrodynamic waves
83.80.Hj Suspensions, dispersions, pastes, slurries, colloids
83.50.Ax Steady shear flows, viscometric flow
66.20.-d Viscosity of liquids; diffusive momentum transport

Periodic sedimentation of three particles in periodic boundary conditions

M. L. Ekiel-Jeżewska and B. U. Felderhof

Phys. Fluids 17, 093102 (2005); http://dx.doi.org/10.1063/1.2008827 (9 pages) | Cited 3 times

Online Publication Date: 30 August 2005

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Solutions of the equations of Stokesian dynamics for point particles are found for periodic boundary conditions with three particles per unit cell of a simple cubic lattice. Two particles per cell move with equal velocity, but three particles per cell usually lead to irregular motion. For a class of initial conditions with special symmetry motions are found that are periodic in time as well as in space. It is shown that there is a range of stability in which the motions are robust under perturbation.
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47.55.Kf Particle-laden flows
47.60.-i Flow phenomena in quasi-one-dimensional systems
47.20.-k Flow instabilities

Dynamics of a suspension confined in a thin cell

Alejandra Alvarez and Rodrigo Soto

Phys. Fluids 17, 093103 (2005); http://dx.doi.org/10.1063/1.2009773 (9 pages) | Cited 6 times

Online Publication Date: 2 September 2005

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A suspension confined between two close parallel plates is studied in the Stokesian regime. The use of boundary integral equations and the lubrication approximation allows computation of the hydrodynamic forces acting on the particles. The forces are long ranged (decaying as R−2) and depend on the orientation of the relative position and velocity of particles. This tensorial character predicts an “antidrag” that is observed in experiments. Also, the far-field forces vanish when a particle is surrounded by an homogeneous suspension, but net forces appear in the presence of abrupt discontinuities of the suspension. The effect of the computed hydrodynamic forces is studied in the dynamics of a cluster of particles falling in a gravitational field, where the different features of the hydrodynamic forces are present. The cluster spreads and deforms from the initial circular shape due to the action of the hydrodynamic forces in the presence of the cluster boundary. The expression for the hydrodynamic forces at long distances allows application of a mean-field approximation, where the forces on a particle can be computed in terms of the particle current field. This approximation gives an excellent numerical agreement with the direct computation of all the hydrodynamic forces, being numerically much faster, yet preserving the accuracy.
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47.55.Kf Particle-laden flows
47.60.-i Flow phenomena in quasi-one-dimensional systems
47.35.-i Hydrodynamic waves
02.60.Nm Integral and integrodifferential equations

Effect of capillary and viscous forces on spreading of a liquid drop impinging on a solid surface

Alexander I. Fedorchenko, An-Bang Wang, and Yi-Hua Wang

Phys. Fluids 17, 093104 (2005); http://dx.doi.org/10.1063/1.2038367 (8 pages) | Cited 8 times

Online Publication Date: 15 September 2005

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The theoretical models for the deformation of a liquid drop impinging on a solid flat surface at the initial and late stages are proposed. It was found that at the initial stage of the drop impact, the thickness of the emerging film decreases rapidly along its radius r, as r−6, that is similar to the splash jet induced by the blunt-body impact on the liquid surface. The thickness of the film levels off with time due to the viscous force, and the late stage of the drop spreading is controlled by the action of viscous and capillary forces. The influence of the capillary forces is localized in the vicinity of the triple line, and it causes the formation of the thick border (blob) on the edge of the spreading drop. An analytical solution of the model in viscous limit reveals that the minimum film thickness scales as Re−2/5 and the drop maximum radius in its maximum extension as Re1/5. The analytical solution for the dynamics of the blob mass growth is also obtained. The kinetic energy of the drop at its maximum extension remains greater than zero in the drop-spreading process even accounting for viscous effect.
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47.55.D- Drops and bubbles
47.55.Kf Particle-laden flows
68.15.+e Liquid thin films
68.08.Bc Wetting
47.27.wg Turbulent jets

Orientation distribution of cylindrical particles suspended in a turbulent pipe flow

Ling-Xin Zhang, Jian-Zhong Lin, and T. L. Chan

Phys. Fluids 17, 093105 (2005); http://dx.doi.org/10.1063/1.2046713 (8 pages) | Cited 3 times

Online Publication Date: 21 September 2005

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A model of turbulent cylindrical particle suspensions is proposed to predict the orientation distribution of particles. The fluctuating equation for the orientation distribution function (ODF) of cylindrical particles is theoretically solved using the method of characteristics. The orientation-correlated terms in the mean equation for the ODF due to the random motion of cylindrical particles are related to the correlations of the mean ODF and the fluid velocity gradient. Thus, the evolution of the mean ODF is described by a modified convection-dispersion equation. The model and modified equation are used to calculate the ODF in a pipe flow numerically. The results compare qualitatively with the experimental data and show that the turbulent dispersion makes cylindrical particles have a broad orientation distribution, while the velocity gradient plays an opposite role. The increase of the particle aspect ratio leads to a less aligned distribution in the vicinity of the axis and a narrower orientation distribution at positions far from the axis.
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47.55.Kf Particle-laden flows
47.27.tb Turbulent diffusion
47.60.-i Flow phenomena in quasi-one-dimensional systems
47.27.T- Turbulent transport processes
47.27.nb Boundary layer turbulence

Streamline topologies near nonsimple degenerate points in two-dimensional flows with double symmetry away from boundaries and an application

F. Gürcan and A. Deliceoğlu

Phys. Fluids 17, 093106 (2005); http://dx.doi.org/10.1063/1.2055527 (7 pages) | Cited 5 times

Online Publication Date: 26 September 2005

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Streamline patterns and their bifurcations in two-dimensional incompressible fluid near simple degenerate critical points away from boundaries have been investigated by Brøns and Hartnack [Phys. Fluids 11, 314 (1999)] using a normal form approach. In this study, their method is extended to a nonsimple degenerate point under certain conditions. A normal form transformation is used to simplify the differential equations of a Hamiltonian system that describes the streamlines. Bifurcations in the flow occur when parameters take certain degenerate values. When the degenerate configuration is perturbed slightly, an unfolding of the system is obtained. From this, we give a complete description of the bifurcations up to codimension two. New flow patterns are found that inflow saddles are connected by a single heteroclinic connection and an interaction of two vortices with opposite rotations appears in the flow. The theory is applied to the patterns and bifurcations found numerically in the studies of Stokes flow in a double-lid-driven rectangular cavity.
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47.54.-r Pattern selection; pattern formation
47.20.Ky Nonlinearity, bifurcation, and symmetry breaking
47.32.C- Vortex dynamics
47.60.-i Flow phenomena in quasi-one-dimensional systems
02.60.Lj Ordinary and partial differential equations; boundary value problems
back to top Particulate, Multiphase, and Granular Flows

Velocity measurements in dry granular avalanches using particle image velocimetry technique and comparison with theoretical predictions

Shiva P. Pudasaini, Shu-San Hsiau, Yongqi Wang, and Kolumban Hutter

Phys. Fluids 17, 093301 (2005); http://dx.doi.org/10.1063/1.2007487 (10 pages) | Cited 13 times

Online Publication Date: 12 September 2005

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Velocity and depth are crucial field variables to describe the dynamics of avalanches of sand or soil or snow and to draw conclusions about their flow behavior. In this paper we present new results about velocity measurements in granular laboratory avalanches and their comparison with theoretical predictions. Particle image velocimetry measurement technique is introduced and used to measure the dynamics of the velocity distribution of free surface and unsteady flows of avalanches of non-transparent quartz particles down a curved chute merging into a horizontal plane from initiation to the runout zone. Velocity distributions at the free surface are determined and in one case also at the bottom from below. Also measured is the settlement of the avalanche in the deposit. For the theoretical prediction we consider the model equations proposed by Pudasaini and Hutter [J. Fluid Mech. 495, 193 (2003) ]. A nonoscillatory central differencing total variation diminishing scheme is implemented to integrate these model equations. It is demonstrated that the theory, numerics, and experimental observations are in excellent agreement. These results can be applied to estimate impact pressures exerted by avalanches on defence structures and infrastructures along the channel and in runout zones.
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47.55.Kf Particle-laden flows
47.20.-k Flow instabilities
47.80.-v Instrumentation and measurement methods in fluid dynamics

The effects of electrostatic forces on the distribution of drops in a channel flow: Two-dimensional oblate drops

Arturo Fernández, Gretar Tryggvason, Judy Che, and Steven L. Ceccio

Phys. Fluids 17, 093302 (2005); http://dx.doi.org/10.1063/1.2043147 (15 pages) | Cited 12 times

Online Publication Date: 16 September 2005

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Numerical simulations are used to examine the effect of an electrostatic field on an emulsion of drops in a channel. The leaky-dielectric theory of Taylor is used to find the electric field, the charge distribution on the drop surface, and the resulting forces. The Navier-Stokes equations are solved using a front-tracking/finite-volume technique. Depending on the ratios of conductivity and permittivity of the drop fluid and the suspending fluid the drops can become oblate or prolate. In addition to normal forces that deform the drops, tangential forces can induce a fluid motion either from the poles of the drops to their equator or from the equator to the poles. In this paper we focus on oblate drops, where both the dielectrophoretic and the electrohydrodynamic interactions of the drops work together to “fibrate” the emulsion by lining the drops up into columns parallel to the electric field. When the flow through the channel is slow, the fibers can extend from one wall to the other. As the flow rate is increased the fibers are broken up and drops accumulate at the channel walls. For high enough flow rate, when the drop interactions are dominated by the fluid shear, the drops remain in suspension. Only two-dimensional systems are examined here, but the method can be used for fully three-dimensional systems as well.
Show PACS
47.65.-d Magnetohydrodynamics and electrohydrodynamics
47.55.D- Drops and bubbles
47.55.Kf Particle-laden flows
47.60.-i Flow phenomena in quasi-one-dimensional systems
47.10.-g General theory in fluid dynamics
47.11.-j Computational methods in fluid dynamics
82.70.Kj Emulsions and suspensions
02.60.Cb Numerical simulation; solution of equations

A direct numerical simulation study of the buoyant rise of bubbles at O(100) Reynolds number

Asghar Esmaeeli and Grétar Tryggvason

Phys. Fluids 17, 093303 (2005); http://dx.doi.org/10.1063/1.2056617 (19 pages) | Cited 18 times

Online Publication Date: 28 September 2005

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Buoyancy-driven motion of bubbles is examined by direct numerical simulations. Two cases, with 48 monodispersed bubbles at two different gas∕liquid combinations, of deformable and nearly spherical bubbles, are simulated. For the nearly spherical bubbles Eo = 0.5, and for the deformable ones Eo = 4, and for both cases N = 8000 and α = 5.8%. This results in math = 91.5 and math = 0.53 for the nearly spherical system and math = 77.6 and math = 3 for the deformable one. The simulations show path oscillations of the bubbles in both cases and shape oscillations of the deformable bubbles. At quasi-steady-state, the distribution of the deformable bubbles is relatively uniform but the spherical bubbles are distributed nonuniformly as a result of the formation of horizontal “rafts.” For both cases, however, the probability density functions of the fluctuation velocities of the bubbles are found to be approximately Gaussian. The temporal autocorrelation functions of the fluctuation velocities show that the horizontal components become uncorrelated faster than the vertical component and the correlation time for the vertical autocorrelation for deformable bubbles is at least twice larger than that for nearly spherical ones.
Show PACS
47.55.D- Drops and bubbles
47.55.Kf Particle-laden flows
47.11.-j Computational methods in fluid dynamics
47.15.-x Laminar flows
47.35.-i Hydrodynamic waves
02.50.Ng Distribution theory and Monte Carlo studies
back to top Laminar Flows

Nested separatrices in simple shear flows: The effect of localized disturbances on stagnation lines

M. C. T. Wilson, P. H. Gaskell, and M. D. Savage

Phys. Fluids 17, 093601 (2005); http://dx.doi.org/10.1063/1.2042488 (11 pages) | Cited 4 times

Online Publication Date: 12 September 2005

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The effects of localized two-dimensional disturbances on the structure of shear flows featuring a stagnation line are investigated. A simple superposition of a planar Couette flow and Moffatt’s [J. Fluid Mech. 18, 1–18 (1964) ] streamfunction for the decay of a disturbance between infinite stationary parallel plates shows that in general the stagnation line is replaced by a chain of alternating elliptic and hyperbolic stagnation points with a separation equal to 2.78 times the half-gap between the plates. The flow structure associated with each saddle point consists of a homoclinic separatrix and two other separatrices which locally diverge but become parallel far from the disturbance. This basic structure repeats to give a sequence of nested separatrices permitting the streamfunction to approach that of simple shear flow far from the disturbance. Using the finite-element method, the specific disturbance caused by a stationary cylinder placed on the stagnation line is considered, and results confirm the existence of the stagnation point chain, with computed separations and velocity damping ratios in very good agreement with those obtained from the Couette-Moffatt superposition. Numerical solutions also illustrate that while Reynolds number greatly affects the stagnation point separation and velocity damping ratio, these two quantities are the same for any pair of adjacent stagnation points in a given chain. Insight gained from the analysis of planar shear flows is applied to the flow in a half-filled horizontal annulus between rotating coaxial cylinders, and is used to explain why only certain flow patterns from the range of mathematically possible structures arise in previous numerical solutions. By way of contrast, the concentric annulus solution is then perturbed to allow for a small eccentricity. The nonuniformity of the intercylinder gap is shown to destroy the chain of stagnation points, but also to unfold additional flow structures not realizable when the gap is uniform.
Show PACS
47.15.-x Laminar flows
47.60.-i Flow phenomena in quasi-one-dimensional systems
47.32.-y Vortex dynamics; rotating fluids
47.54.-r Pattern selection; pattern formation
02.70.Dh Finite-element and Galerkin methods

Analytical calculation of slip flow in lattice Boltzmann models with kinetic boundary conditions

M. Sbragaglia and S. Succi

Phys. Fluids 17, 093602 (2005); http://dx.doi.org/10.1063/1.2044829 (8 pages) | Cited 52 times

Online Publication Date: 12 September 2005

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We present a mathematical formulation of kinetic boundary conditions for lattice Boltzmann schemes in terms of reflection, slip, and accommodation coefficients. It is analytically and numerically shown that, in the presence of a nonzero slip coefficient, the lattice Boltzmann develops a physical slip flow component at the wall. Moreover, it is shown that the slip coefficient can be tuned in such a way to recover quantitative agreement with the analytical and experimental results up to second order in the Knudsen number.
Show PACS
47.45.Gx Slip flows and accommodation
05.50.+q Lattice theory and statistics (Ising, Potts, etc.)
05.20.Dd Kinetic theory
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