POF: Particulate, Multiphase, and Granular Flows http://scitation.aip.org/ POF: Particulate, Multiphase, and Granular Flows A fully resolved numerical simulation of turbulent flow past one or several spherical particles http://link.aip.org/link/?PHF/24/013303/1&agg=rss L. Botto and A. Prosperetti<br/> The flow past one or nine spheres arranged in a plane lattice held fixed in a stream of decaying homogeneous isotropic turbulence is studied by means of fully resolved Navier-Stokes simulations. The particle radius is 35 times the Kolmogorov length and about 1/3 of the integral length scale. The mea ... [Phys. Fluids 24, 013303 (2012)] published Tue Jan 31, 2012. Rheological measurements of large particles in high shear rate flows http://link.aip.org/link/?PHF/24/013302/1&agg=rss Erin Koos, Esperanza Linares-Guerrero, Melany L. Hunt, and Christopher E. Brennen<br/> This paper presents experimental measurements of the rheological behavior of liquid-solid mixtures at moderate Stokes and Reynolds numbers. The experiments were performed in a coaxial rheometer that was designed to minimize the effects of secondary flows. By changing the shear rate, particle size, a ... [Phys. Fluids 24, 013302 (2012)] published Fri Jan 27, 2012. Intermittent features of inertial particle distributions in turbulent premixed flames http://link.aip.org/link/?PHF/23/123304/1&agg=rss F. Battista, F. Picano, G. Troiani, and C. M. Casciola<br/> Clustering is widely observed in many turbulent flows, where it results from the inability of finite inertia particles to comply with the different time scales, which characterize a turbulent field. Depending on their inertia, particles are found to be instantaneously organized in clusters, whose si ... [Phys. Fluids 23, 123304 (2011)] published Fri Dec 30, 2011. Three-dimensional numerical simulation of drops suspended in Poiseuille flow at non-zero Reynolds numbers http://link.aip.org/link/?PHF/23/123303/1&agg=rss Amireh Nourbakhsh, Saeed Mortazavi, and Yaser Afshar<br/> A finite difference/front tracking method is used to study the motion of three-dimensional deformable drops suspended in plane Poiseuille flow at non-zero Reynolds numbers. A parallel version of the code was used to study the behavior of suspension on a reasonable grid resolution (128 x 128 x 128 gr ... [Phys. Fluids 23, 123303 (2011)] published Wed Dec 7, 2011. Inertial migration of deformable capsules in channel flow http://link.aip.org/link/?PHF/23/123302/1&agg=rss Alex Kilimnik, Wenbin Mao, and Alexander Alexeev<br/> Using three-dimensional computer simulations, we study the cross-stream inertial migration of neutrally buoyant deformable particles in a pressure-driven channel flow. The particles are modeled as elastic shells filled with a viscous fluid. We show that the particles equilibrate in a channel flow at ... [Phys. Fluids 23, 123302 (2011)] published Mon Dec 5, 2011. Turbulence modification and heat transfer enhancement by inertial particles in turbulent channel flow http://link.aip.org/link/?PHF/23/123301/1&agg=rss J. G. M. Kuerten, C. W. M. van der Geld, and B. J. Geurts<br/> We present results of direct numerical simulation of turbulence modification and heat transfer in turbulent particle-laden channel flow and show an enhancement of the heat transfer and a small increase in the friction velocity when heavy inertial particles with high specific heat capacity are added ... [Phys. Fluids 23, 123301 (2011)] published Mon Dec 5, 2011. Acceleration statistics of solid particles in turbulent channel flow http://link.aip.org/link/?PHF/23/113304/1&agg=rss R. Zamansky, I. Vinkovic, and M. Gorokhovski<br/> Direct numerical simulations (DNS) are used here to study inertial particle acceleration statistics in the near-wall region of a turbulent channel flow. The study is motivated by observations in homogeneous isotropic turbulence (HIT) suggesting that when particle inertia increases, particle accelera ... [Phys. Fluids 23, 113304 (2011)] published Mon Nov 28, 2011. Simulations of granular bed erosion due to laminar shear flow near the critical Shields number http://link.aip.org/link/?PHF/23/113303/1&agg=rss J. J. Derksen<br/> Direct numerical simulations of granular beds consisting of uniformly sized spherical particles being eroded by a shear flow of Newtonian liquid have been performed. The lattice-Boltzmann method has been used for resolving the flow of the interstitial liquid. Fluid and solid dynamics are fully coupl ... [Phys. Fluids 23, 113303 (2011)] published Thu Nov 17, 2011. Rheology of binary granular mixtures in the dense flow regime http://link.aip.org/link/?PHF/23/113302/1&agg=rss Anurag Tripathi and D. V. Khakhar<br/> We study the rheology of granular mixtures in a steady, fully developed, gravity-driven flow on an inclined plane, by means of discrete element method (DEM) simulations. Results are presented for a single component system and binary mixtures with particles of different size and density. Inclination ... [Phys. Fluids 23, 113302 (2011)] published Wed Nov 9, 2011. Experimental investigation of the propagation of a planar shock wave through a two-phase gas-liquid medium http://link.aip.org/link/?PHF/23/113301/1&agg=rss A. Chauvin, G. Jourdan, E. Daniel, L. Houas, and R. Tosello<br/> We conducted a series of shock tube experiments to study the influence of a cloud of water droplets on the propagation of a planar shock wave. In a vertically oriented shock tube, the cloud of droplets was released downwards into the air at atmospheric pressure while the shock wave propagated upward ... [Phys. Fluids 23, 113301 (2011)] published Mon Nov 7, 2011. From streamline jumping to strange eigenmodes: Bridging the Lagrangian and Eulerian pictures of the kinematics of mixing in granular flows http://link.aip.org/link/?PHF/23/103302/1&agg=rss Ivan C. Christov, Julio M. Ottino, and Richard M. Lueptow<br/> Through a combined computationalexperimental study of flow in a slowly rotating quasi-two-dimensional container, we show several new aspects related to the kinematics of granular mixing. In the Lagrangian frame, for small numbers of revolutions, the mixing pattern is captured by a model termed strea ... [Phys. Fluids 23, 103302 (2011)] published Mon Oct 24, 2011. On the dynamics and breakup of a bubble rising in a turbulent flow http://link.aip.org/link/?PHF/23/103301/1&agg=rss F. Ravelet, C. Colin, and F. Risso<br/> Experimental investigations of the dynamics of a deformable bubble rising in a uniform turbulent flow are reported. The turbulence is characterized by fast particle image velocimetry. Time-resolved evolutions of bubble translation, rotation, and deformation are determined by three-dimensional shape ... [Phys. Fluids 23, 103301 (2011)] published Tue Oct 11, 2011. Neutrally buoyant particle dynamics in fluid flows: Comparison of experiments with Lagrangian stochastic models http://link.aip.org/link/?PHF/23/093304/1&agg=rss Themistoklis P. Sapsis, Nicholas T. Ouellette, Jerry P. Gollub, and George Haller<br/> We study the validity of various models for the dynamics of finite-sized particles in fluids by means of a direct comparison between theory and experimentally measured trajectories and velocities of large numbers of particles in chaotic two-dimensional flow. Our analysis indicates that finite-sized ... [Phys. Fluids 23, 093304 (2011)] published Fri Sep 16, 2011. Instabilities in the homogeneous cooling of a granular gas: A quantitative assessment of kinetic-theory predictions http://link.aip.org/link/?PHF/23/093303/1&agg=rss Peter P. Mitrano, Steven R. Dahl, Daniel J. Cromer, Michael S. Pacella, and Christine M. Hrenya<br/> Previous work has indicated that inelastic grains undergoing homogeneous cooling may be unstable, giving rise to the formation of velocity vortices, which may also lead to particle clustering. In this effort, molecular dynamics (MD) simulations are performed over a wide parameter space to determine ... [Phys. Fluids 23, 093303 (2011)] published Thu Sep 15, 2011. On particle spin in two-way coupled turbulent channel flow simulations http://link.aip.org/link/?PHF/23/093302/1&agg=rss Lihao Zhao and Helge I. Andersson<br/> The rotational motion of spherical particles suspended in a turbulent flow field may not necessarily adapt to the fluid rotation, i.e., the particle spin may be different from the fluid vorticity. The translational and rotational motions of tiny particles are described in a Lagrangian framework usin ... [Phys. Fluids 23, 093302 (2011)] published Tue Sep 6, 2011. Preferential concentration and rise velocity reduction of bubbles immersed in a homogeneous and isotropic turbulent flow http://link.aip.org/link/?PHF/23/093301/1&agg=rss A. Aliseda and J. C. Lasheras<br/> The behavior of small spherical bubbles immersed in a homogeneous isotropic turbulent carrier flow of a heavier fluid has been experimentally studied. Air bubbles with diameters between 10 and 900 [mu]m were injected in the test section of a horizontal water channel and allowed to interact with the ... [Phys. Fluids 23, 093301 (2011)] published Tue Sep 6, 2011. First-order virial expansion of short-time diffusion and sedimentation coefficients of permeable particles suspensions http://link.aip.org/link/?PHF/23/083303/1&agg=rss Bogdan Cichocki, Maria L. Ekiel-Jezewska, Gerhard Nagele, and Eligiusz Wajnryb<br/> For suspensions of permeable particles, the short-time translational and rotational self-diffusion coefficients, and collective diffusion and sedimentation coefficients are evaluated theoretically. An individual particle is modeled as a uniformly permeable sphere of a given permeability, with the in ... [Phys. Fluids 23, 083303 (2011)] published Wed Aug 31, 2011. Roles of particle-wall and particle-particle interactions in highly confined suspensions of spherical particles being sheared at low Reynolds numbers http://link.aip.org/link/?PHF/23/083302/1&agg=rss Ashok S. Sangani, Andreas Acrivos, and Philippe Peyla<br/> The roles of particle-wall and particle-particle interactions are examined for suspensions of spherical particles in a viscous fluid being confined and sheared at low Reynolds numbers by two parallel walls moving with equal but opposite velocities. Both particle-wall and particle-particle interactio ... [Phys. Fluids 23, 083302 (2011)] published Thu Aug 11, 2011. The effect of interstitial fluid viscosity on particle segregation in a slurry rotating drum http://link.aip.org/link/?PHF/23/083301/1&agg=rss S. H. Chou, C. C. Liao, and S. S. Hsiau<br/> Although the segregation of dry granular surface flow has been widely studied, cases where the air is completely replaced by a liquid still remain unexplored. In this study, we report on experiments performed to investigate the phenomena of particle segregation and flowing behavior in a rotating dru ... [Phys. Fluids 23, 083301 (2011)] published Wed Aug 10, 2011. Granular collapse in a fluid: Role of the initial volume fraction http://link.aip.org/link/?PHF/23/073301/1&agg=rss L. Rondon, O. Pouliquen, and P. Aussillous<br/> The collapse of a granular column in a viscous liquid is experimentally investigated. The morphology of the deposits is shown to be mainly controlled by the initial volume fraction of the granular mass and not by the aspect ratio of the column, an observation which differs from dry granular collapse ... [Phys. Fluids 23, 073301 (2011)] published Fri Jul 1, 2011. Break-up of suspension drops settling under gravity in a viscous fluid close to a vertical wall http://link.aip.org/link/?PHF/23/063302/1&agg=rss Anna Mylyk, Walter Meile, Gunter Brenn, and Maria L. Ekiel-Jezewska<br/> The evolution of suspension drops sedimenting under gravity in a viscous fluid close to a vertical wall was studied experimentally and numerically with the use of the point-force model, in the Stokes flow regime. The fluid inside and outside the drop was identical. The initial distribution of the su ... [Phys. Fluids 23, 063302 (2011)] published Fri Jun 24, 2011.