Discharge of soft and hard grains and their mixtures from 2D silos

The outflow characteristics of hard grains from containers with narrow basal openings have been extensively studied. Recently, it was shown that soft, low-frictional grains can behave qualitatively different from the behavior of rigid grains. We compare experimentally the discharge of monodisperse hard spheres, soft spheres and mixtures of both from a quasi-two dimensional (2D) silo. The experiments demonstrate the remarkable consequences of the addition of few hard particles to a soft particle ensemble, as well as the gradual transition between the two limiting cases of pure one-component materials.

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Sound damping in soft particle packings: the interplay between configurational disorder and inelasticity

Soft Matter ◽

10.1039/d0sm02018d ◽

2021 ◽

Vol 17 (15) ◽

pp. 4204-4212

Author(s):

Kuniyasu Saitoh ◽

Hideyuki Mizuno

Keyword(s):

Soft Particle ◽

Two Dimensional ◽

Particle Packings

We numerically investigate sound damping in disordered two-dimensional soft particle packings. Our findings suggest that sound damping in soft particle packings is determined by the interplay between elastic heterogeneities and inelasticity.

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METHODS TO COMPUTE PRESSURE AND WALL TENSION IN FLUIDS CONTAINING HARD PARTICLES

International Journal of Modern Physics C ◽

10.1142/s0129183112400116 ◽

2012 ◽

Vol 23 (08) ◽

pp. 1240011 ◽

Cited By ~ 12

Author(s):

DEBABRATA DEB ◽

DOROTHEA WILMS ◽

ALEXANDER WINKLER ◽

PETER VIRNAU ◽

KURT BINDER

Keyword(s):

Comparative Evaluation ◽

Hard Spheres ◽

Excess Energy ◽

Attractive Potential ◽

Wall Tension ◽

Pressure Tensor ◽

Colloidal Systems ◽

Polymer Mixtures ◽

Hard Particles ◽

Mutual Agreement

Colloidal systems are often modeled as fluids of hard particles (possibly with an additional soft attraction, e.g. caused by polymers also contained in the suspension). In simulations of such systems, the virial theorem cannot be straightforwardly applied to obtain the components of the pressure tensor. In systems confined by walls, it is hence also not straightforward to extract the excess energy due to the wall (the “wall tension”) from the pressure tensor anisotropy. A comparative evaluation of several methods to circumvent this problem is presented, using as examples fluids of hard spheres and the Asakura–Oosawa model of colloid-polymer mixtures with a size ratio q = 0.15 (for which the effect of the polymers can be integrated out to yield an effective attractive potential between the colloids). Factors limiting the accuracy of the various methods are carefully discussed, and controlling these factors very good mutual agreement between the various methods is found.

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An Analysis of Deep Submerged Multiple-Port Buoyant Discharges

Journal of Heat Transfer ◽

10.1115/1.3450757 ◽

1977 ◽

Vol 99 (4) ◽

pp. 648-654 ◽

Cited By ~ 3

Author(s):

L. D. Kannberg ◽

L. R. Davis

Keyword(s):

Experimental Data ◽

Experimental Study ◽

Gradual Transition ◽

Two Dimensional ◽

Buoyant Jets ◽

Multiple Jets ◽

Buoyant Discharges

The results of an experimental study of deep submerged multiple-port thermal discharges are compared to the predictions of a theory treating the dilution of merging multiple-port buoyant jets discharge from a row of equally spaced ports. The paper summarizes the considerable alteration of the Hirst [11] model necessary to adequately treat merging multiple jets. The essential features of the analysis are: (1) the gradual transition of the profiles from simple axisymmetric profiles to merging profiles and finally to fully merged, pseudo-slot, two-dimensional profiles, and (2) an entrainment based on the available entrainment surface. Results indicate that the overprediction of plume characteristics associated with certain other models as compared to experimental data may be overcome using such an analysis and that suitable prediction may be obtained.

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Effect of hydrophobic core on the electrophoresis of a diffuse soft particle

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2016.0942 ◽

2017 ◽

Vol 473 (2199) ◽

pp. 20160942 ◽

Cited By ~ 8

Author(s):

Partha P. Gopmandal ◽

S. Bhattacharyya ◽

H. Ohshima

Keyword(s):

Hydrophobic Surface ◽

Weak Field ◽

Gradual Transition ◽

Soft Particle ◽

Hydrophobic Core ◽

Particle Mobility ◽

The Core ◽

Segment Distribution ◽

Low Charge ◽

The Impact

Electrophoresis of a diffuse soft particle with a charged hydrophobic core is considered under the weak field and low charge density assumptions. The hydrophobic surface of the core is coated with a diffuse polyelectrolyte layer (PEL) in which a gradual transition of the polymer segment distribution from the impenetrable core to the surrounding electrolyte medium is considered. A mathematical model is adopted to analyse the impact of the core hydrophobicity on the diffuse soft particle electrophoresis. The mobility based on the present model for the limiting cases such as bare colloids with hydrophobic core and soft particles with no-slip rigid cores are in good agreement with the existing results. The presence of PEL charges produces the impact of the core hydrophobicity on the soft particle mobility different from the corresponding bare colloid with hydrophobic surface in an electrolyte medium. The impact of the core hydrophobicity is subtle when the hydrodynamic screening length of the PEL is low. Reversal in mobility can be achieved by tuning the core hydrophobicity for an oppositely charged core and PEL.

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From Hard Spheres to Soft Spheres: The Effect of Copolymer Composition on the Structure of Micellar Cubic Phases Formed by Diblock Copolymers in Aqueous Solution

Langmuir ◽

10.1021/la991035j ◽

2000 ◽

Vol 16 (6) ◽

pp. 2508-2514 ◽

Cited By ~ 82

Author(s):

Ian W. Hamley ◽

Christophe Daniel ◽

Withawat Mingvanish ◽

Shao-Min Mai ◽

Colin Booth ◽

...

Keyword(s):

Aqueous Solution ◽

Diblock Copolymers ◽

Hard Spheres ◽

Copolymer Composition ◽

Cubic Phases ◽

Soft Spheres

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Description of the Adsorption Equilibrium with Consideration to the Decreasing Availability of Space in the Course of Mobile Adsorption of a Single Gas on a Homogenous Surface of Solid

Polish Hyperbaric Research ◽

10.2478/phr-2018-0016 ◽

2018 ◽

Vol 64 (3) ◽

pp. 25-38

Author(s):

Jerzy K. Garbacz ◽

Ewa Kopkowska ◽

Barbara Rymian

Keyword(s):

Gas Adsorption ◽

Hard Spheres ◽

Two Dimensional ◽

Two Phase ◽

Solid Adsorbent ◽

Proposed Model ◽

Adsorption Monolayer ◽

Mobile Adsorption ◽

The Given ◽

Component Adsorption

Abstract The subsequent stages of the process of formulation of the equation for gas adsorption on a homogenous surface of a solid adsorbent were presented based on the general expression for the canonical ensemble of the mobile single-component adsorption monolayer. The method of formulating the configuration integral of the proposed model was discussed in detail where the role both of the attraction and repulsion between adsorbed molecules was emphasised. The expression for the probability of finding a molecule in a specified point on a surface of an adsorbent was modified by determining its magnitude by the adsorbent concentration. The expression for the so-called effective surface of the adsorbent was obtained by adapting a two-dimensional analogue equation of state hard spheres – Van der Waals equation (2D-vdW) and Reis-Frisch-Lebowitz equation accordingly (2D-RFL). As a result, two new adsorption equations were formulated which differ in detail concerning the adsorbate-adsorbate repulsion. On each of these equations theoretical analysis was performed in terms of two-dimensional phase transformation. In both cases it was proved that the proposed solution allows for the presence of two-phase transformations of the first type which is the gas-liquid condensation and solidification liquid-solid. The verification of the given approach was supplemented by the description of the experimental data given in reference literature and by obtaining a very good correlation between the theory and experiment.

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A molecular dynamics study of the structural stability of a two-dimensional soft-spheres binary alloy

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/7/12/004 ◽

1995 ◽

Vol 7 (12) ◽

pp. 2395-2407 ◽

Cited By ~ 1

Author(s):

S Goncalves ◽

J R Iglesias

Keyword(s):

Molecular Dynamics ◽

Structural Stability ◽

Binary Alloy ◽

Two Dimensional ◽

Soft Spheres

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Evidence of Structural Inhomogeneities in Hard-Soft Dimeric Particles without Attractive Interactions

Materials ◽

10.3390/ma13010084 ◽

2019 ◽

Vol 13 (1) ◽

pp. 84 ◽

Cited By ~ 1

Author(s):

Gianmarco Munaò ◽

Franz Saija

Keyword(s):

Hard Spheres ◽

Hard Core ◽

Fluid Phase ◽

Colloidal Dispersion ◽

Systematic Investigation ◽

Distribution Functions ◽

Structure Factors ◽

Soft Spheres ◽

Wide Range ◽

Structural Inhomogeneities

We perform Monte Carlo simulations of a simple hard-soft dimeric model constituted by two tangent spheres experiencing different interactions. Specifically, two hard spheres belonging to different dimers interact via a bare hard-core repulsion, whereas two soft spheres experience a softly repulsive Hertzian interaction. The cross correlations are soft as well. By exploring a wide range of temperatures and densities we investigate the capability of this model to document the existence of structural inhomogeneities indicating the possible onset of aggregates, even if no attraction is set. The fluid phase behavior is studied by analyzing structural and thermodynamical properties of the observed structures, in particular by computing radial distribution functions, structure factors and cluster size distributions. The numerical results are supported by integral equation theories of molecular liquids which allow for a finer and faster spanning of the temperature-density diagram. Our results may serve as a framework for a more systematic investigation of self-assembled structures of functionalized hard-soft dimers able to aggregate in a variety of structures widely oberved in colloidal dispersion.

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