Structure and rheology of suspensions of spherical strain-hardening capsules

Aouane, Othmane; Scagliarini, Andrea; Harting, Jens

doi:10.1017/jfm.2020.1040

Cited by 15 publications

(21 citation statements)

References 86 publications

(179 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…( 33), N 1 vanishes in the small γ limit. For finite γ, it is a concave function, which is consistent with the behavior observed in simulations of emulsions [17,18,29]. The concavity is increasing with increasing φ, and at large φ we see a decrease of N 1 / γ at large γ.…”

Section: Rheological Properties a Steady-state Rheology Shear Thinningsupporting

confidence: 87%

“…In a simple picture, shear thinning is a consequence of the fact that when the applied shear rate increases, stresses lead to increasing particle deformation, so that particles can better accommodate the applied flow. This can be interpreted in terms of an effective volume fraction φ eff φ decreasing with increasing applied stress, such that the viscosity is well approximated as η Hard (φ eff ), where η Hard (φ) is the viscosity for a suspension of hard spheres at volume fraction φ [21,28,29]. Beyond this simple qualitative picture, however, there is to the best of our knowledge currently no theory aiming at capturing the essential features of shear thinning for athermal suspensions of soft particles.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Microscopically grounded constitutive model for dense suspensions of soft particles below jamming

Cuny¹,

Bertin²,

Mari³

2023

Preprint

View full text Add to dashboard Cite

We derive from particle-level dynamics a constitutive model describing the rheology of twodimensional dense soft suspensions below the jamming transition, in a regime where hydrodynamic interactions between particles are screened. Based on a statistical description of particle dynamics, we obtain through a set of physically plausible approximations a non-linear tensorial evolution equation for the deviatoric part of the stress tensor, involving the strain-rate and vorticity tensors. This tensorial evolution equation involves singular terms usually not taken into account in phenomenological constitutive models, which most often assume a regular expansion in terms of the stress tensor. All coefficients appearing in the equation have known expressions in terms of the microscopic parameters of the model. The predictions of this microscopically grounded constitutive model have several qualitative features that are specific to the rheology of soft suspensions measured in experiments or simulations. The model shows a typical behavior of polymeric visco-elastic materials, such as normal stress differences quadratic in the shear rate γ, as well as typical behaviors of suspensions of stiff particles, such as a particle pressure linear in γ and a zero-shear viscosity diverging at the jamming transition. The model also predicts a sharper shear thinning than other visco-elastic models at small shear rates, in qualitative agreement with experimental observations. Furthermore the shear thinning follows a critical scaling close to the jamming transition.

show abstract

Section: Rheological Properties a Steady-state Rheology Shear Thinningsupporting

confidence: 87%

Section: Introductionmentioning

confidence: 99%

Microscopically grounded constitutive model for dense suspensions of soft particles below jamming

Cuny¹,

Bertin²,

Mari³

2023

Preprint

View full text Add to dashboard Cite

show abstract

“…The linear dependency with respect to the shear rate rules out some significant contribution of migration mechanisms due to drop deformability. This result is consistent with some simulation results showing a weak dependence of the normal forces when varying Ca [54].…”

supporting

confidence: 93%

Viscous resuspension of droplets

Maleki,

de Loubens,

Bodiguel

2021

Preprint

View full text Add to dashboard Cite

Using absorbance measurements through a Couette cell containing an emulsion of buoyant droplets, volume fraction profiles are measured at various shear rates. These viscous resuspension experiments allow a direct determination of the normal stress in connection with the suspension balance model that has been developed for suspensions of solid particles. The results unambigously show that the normal viscosity responsible for the shear-induced migration of the droplets is the same as for rigid particles, even at moderate capillary numbers where coalescence occurs, and independently of the polydispersity. This implies that neither the particle deformation nor the detail of contact interactions play an important role on shear-induced migration.

show abstract

“…For more details on our implementation, we refer the reader to some of our previous publications [18,19,25,31–36].…”

Section: Methodsmentioning

confidence: 99%

Lattice Boltzmann simulations of drying suspensions of soft particles

Wouters

Aouane

Sega

et al. 2021

Phil. Trans. R. Soc. A.

Self Cite

View full text Add to dashboard Cite

The ordering of particles in the drying process of a colloidal suspension is crucial in determining the properties of the resulting film. For example, microscopic inhomogeneities can lead to the formation of cracks and defects that can deteriorate the quality of the film considerably. This type of problem is inherently multiscale and here we study it numerically, using our recently developed method for the simulation of soft polymeric capsules in multicomponent fluids. We focus on the effect of the particle softness on the film microstructure during the drying phase and how it relates to the formation of defects. We quantify the order of the particles by measuring both the Voronoi entropy and the isotropic order parameter. Surprisingly, both observables exhibit a non-monotonic behaviour when the softness of the particles is increased. We further investigate the correlation between the interparticle interaction and the change in the microstructure during the evaporation phase. We observe that the rigid particles form chain-like structures that tend to scatter into small clusters when the particle softness is increased. This article is part of the theme issue ‘Progress in mesoscale methods for fluid dynamics simulation’.

show abstract

Structure and rheology of suspensions of spherical strain-hardening capsules

Abstract: Abstract

Cited by 15 publications

References 86 publications

Microscopically grounded constitutive model for dense suspensions of soft particles below jamming

Microscopically grounded constitutive model for dense suspensions of soft particles below jamming

Viscous resuspension of droplets

Lattice Boltzmann simulations of drying suspensions of soft particles

Contact Info

Product

Resources

About