Softening of aged fluids in start-up flows of dense suspensions

Kurokawa, Aika; Ichihara, Mie; Kurita, Kei

doi:10.1016/j.jnnfm.2014.12.011

Cited by 4 publications

(4 citation statements)

References 34 publications

(46 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results depicted in Fig. 7 are in qualitative agreement with previous observations reported for various soft colloidal materials [20][21][22][23][24]30,34]. The increase of the amplitude of the stress overshoot is generally associated with aging phenomena.…”

Section: B Agingsupporting

confidence: 90%

“…Understanding the way soft glasses yield upon flow inception is an important issue. The control of the startup flow response of soft materials is crucial in many manufacturing processes where pressure overshoots can damage the processing tools or be detrimental to the quality of the final products [30]. On a fundamental level, the transient response of soft materials contains the intimate physical mechanisms at the origin of their complex rheology.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Transient dynamics of soft particle glasses in startup shear flow. Part II: Memory and aging

Dio

Khabaz

Bonnecaze

et al. 2022

Journal of Rheology

View full text Add to dashboard Cite

We explore the rheology during a startup flow of well-characterized polyelectrolyte microgel suspensions, which form soft glasses above the jamming concentration. We present and discuss results measured using different mechanical histories focusing on the variations of the static yield stress and yield strain. The behavior of the shear stress growth function is affected by long-lived residual stresses and strains that imprint a slowly decaying mechanical memory inside the materials. The startup flow response is not reversible upon flow reversal and the amplitude of the static yield stress increases with the time elapsed after rejuvenation. We propose an experimental protocol that minimizes the directional memory and we analyze the effect of aging. The static yield strain γp and the reduced static yield stress σp/ σy, where σy is the dynamic yield stress measured from steady flow measurements, are in good agreement with our previous simulations [Khabaz et al., “Transient dynamics of soft particle glasses in startup shear flow. Part I: Microstructure and time scales,” J. Rheol. 65, 241 (2021)]. Our results demonstrate the need to consider memory and aging effects in transient measurements on soft particle glasses.

show abstract

Section: B Agingsupporting

confidence: 90%

Section: Introductionmentioning

confidence: 99%

Transient dynamics of soft particle glasses in startup shear flow. Part II: Memory and aging

Dio

Khabaz

Bonnecaze

et al. 2022

Journal of Rheology

View full text Add to dashboard Cite

show abstract

“…This phenomenology is quite general and has been reported in a variety of materials as different as colloidal glasses [10][11][12][13][14][15][16][17][18][19][20][21][22], metallic glasses [23][24][25], colloidal gels [26][27][28][29][30][31][32][33][34][35][36], nanocomposites [37], dense suspensions of soft particles [38][39][40][41][42][43][44][45][46][47], emulsions and foams [48][49][50][51], polymer melts and solutions [52][53][54][55][56][57]. Transient yielding is vital for process design since the static yield stress can generate pressure perturbations during st...…”

Section: Introductionmentioning

confidence: 76%

“…Whereas hard particle suspensions have been widely studied, there exist far less systematic studies of the transient flow rheology of SPGs. Yet startup flows of dense suspensions of thermosensitive microgels [40,44], polyethylene oxide-protected silica particles [38], multiarm star polymers [39], concentrated emulsions [48,49] dispersions of wax crystal in oil [45], Carbopol suspensions [42] are characterized by a rich phenomenology including stress overshoots. The height of the peak usually increases with the time that the system has spent at rest after preshearing, but its location does not [38,39].…”

Section: Introductionmentioning

confidence: 99%

Transient dynamics of soft particle glasses in startup shear flow. Part I: Microstructure and time scales

Khabaz

Dio

Cloître

et al. 2021

Journal of Rheology

View full text Add to dashboard Cite

The rheology and the microstructure of soft particle glasses during startup flow are studied using three-dimensional particle-dynamics simulations at different particle volume fractions and shear rates. The behavior of transient stress depends on the applied shear rate. At large shear rate, soft particle glasses exhibit a static yield stress signaled by a stress overshoot followed by a relaxation to a steady-state value. The buildup of the stress is driven by an interplay between structural anisotropy due to an accumulation of particles along the compression axis and a depletion along the extension axis, and compression of particles which are soft and deformable.At low shear rate, the stress increase is monotonic and without stress overshoot. The time scale at which structural anisotropy and the stress are maximum is correlated to the non-affine dynamics of SPGs through the persistence time of shear-induced particle collisions and to the residence time of particles inside their transient cages . The static yield strain p  and the reduced static yield stress / py  , where y  is the dynamic yield stress deduced from steady flow measurements, follow universal behaviors when correlated with the dimensional shear rate 0 / s G  & , s being the suspending fluid viscosity and 0 G the storage modulus, which expresses the competition between elastic restoring forces and viscous dissipation. Dense suspensions of thermosensitive core-shell colloids, star-like micelles, and poly(ethylene oxide)-protected silica particles follow the same universal curves suggesting the generality of our results.

show abstract

Shear thickening and dynamic glass transition of concentrated suspensions. State of the problem

Malkin

Куличихин

2016

Colloid J

View full text Add to dashboard Cite

Softening of aged fluids in start-up flows of dense suspensions

Cited by 4 publications

References 34 publications

Transient dynamics of soft particle glasses in startup shear flow. Part II: Memory and aging

Transient dynamics of soft particle glasses in startup shear flow. Part II: Memory and aging

Transient dynamics of soft particle glasses in startup shear flow. Part I: Microstructure and time scales

Shear thickening and dynamic glass transition of concentrated suspensions. State of the problem

Contact Info

Product

Resources

About