Experiments on 2-D suspensions

Bouillot, Jerome; Camoin, C.; Belzons, M.; Blanc, Robert; Guyon, E.

doi:10.1016/0001-8686(82)80026-2

Cited by 19 publications

(13 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This has been observed experimentally (Bouillot et al, 1982;Graham and Bird, 1984), as well as with computer simulations (Durlofsky and Brady, 1989). Laun (1988) indicates that with SANS measurements large density fluctuations were observed.…”

Section: Comparison With Previously Reported Resultssupporting

confidence: 64%

“…Due to some type of instability the order can break up and there is a sudden severe rise in viscosity. This rise can be due to cluster formation, which is well known to occur in dispersions with only hydrodynamic interactions (Brady and Bossis, 1985;Bouillot et al, 1982;Graham and Bird, 1984). Then the dispersion possibly orders again, leading to the low viscosity after some time.…”

Section: (D) Note the Difference In Vertical Scaling Between Figs mentioning

confidence: 99%

See 1 more Smart Citation

Time‐dependent behavior and wall slip in concentrated shear thickening dispersions

Boersma

Baets

Lavèn

et al. 1991

Journal of Rheology

View full text Add to dashboard Cite

SynopsisThe viscosity of concentrated shear thickening dispersions was measured as a function of shear rate, Couette cylinder size, and time. The level of the low shear rate viscosity, which was found to be independent of system size and time, could bc predicted by the equation of Frankel and Acrivos. At shear rates above the critical shear rate for shear thickening in highly concentrated (#> 0.57) dispersions of monodispcrse particles strong viscosity instabilities were detected, together with a dependence on cylinder size. The instabilities are attributed to reversible order-disorder transitions, e.g., from strings to clusters. This dependence on cylinder size is due to wall slip, slipping planes in the dispersion, and even plug flow in the gap. With less concentrated or polydisperse dispersions the effects are much less severe but there is thixotropy, probably due to a reordering of the dispersion.

show abstract

Section: Comparison With Previously Reported Resultssupporting

confidence: 64%

Section: (D) Note the Difference In Vertical Scaling Between Figs mentioning

confidence: 99%

Time‐dependent behavior and wall slip in concentrated shear thickening dispersions

Boersma

Baets

Lavèn

et al. 1991

Journal of Rheology

View full text Add to dashboard Cite

show abstract

“…The predicted asymptotic behavior is consistent with the computer simulation of Brady and Bossis [13] and the experimental work of Bouillot et al [23] for the Newtonian case. To make the quasi-static model better reflect the changes of microstructure during shear, the phenomenological assumptions that the maximum packing fractions were sheardependent were employed.…”

Section: Resultssupporting

confidence: 88%

“…Batchelor [21] and Schowalter [22] have provided some quasi-steady analyses to derive the rheological properties of suspension mechanics by using the method of volumeaverage process. Their results agree with the shear monolayer experiment of Bouillot et al [23], verifying the formation of an infinite cluster with maximum packing ~b,, and singular viscosity, which is the same as that found by Frankel and Acrivos [4]. But, in the spatially periodic case, the infinite cluster resulting from the lubrication forces has an 0(5) contact time.…”

Section: Effective Viscositysupporting

confidence: 89%

Shear viscosity of slightly-elastic concentrated suspensions at low and high shear rates

Wang

Cheau

1988

Rheol Acta

View full text Add to dashboard Cite

A quasi-static asymptotic analysis is employed to investigate the elastic effects of fluids on the shear viscosity of highly concentrated suspensions at low and high shear rates. First a brief discussion is presented on the difference between a quasi-static analysis and the periodic-dynamic approach. The critical point is based on the different order-of-contact time between particles. By considering the motions between a particle with N near contact point particles in a two-dimensional "cell" structure and incorporating the concept of shear-dependent maximum packing fraction reveals the structural evolution of the suspension under shear and a newly asymptotic framework is devised. In order to separate the influence of different elastic mechanisms, the second-order Rivlin-Ericksen fluid assumption for describing normal-stress coefficients at low shear rates and Harnoy's constitutive equation for accounting for the stress relaxation mechanism at high shear rates are employed. The derived formulation shows that the relative shear viscosity is characterized by a recoverable shear strain, SR, at low shear rates if the second normal-stress difference can be neglected, and Deborah number, De, at high shear rates. The predicted values of the viscosities increase with SR, but decrease with De. The role of S R in the matrix is more pronounced than that of De. These tendencies are significant when the maximum packing fraction is considered to be shear-dependent. The results are consistent with that of Frankel and Acrivos in the case of a Newtonian suspension, except for when the different divergent threshhold is given as [ 1 -(~/qSm)l/2 ] --1.

show abstract

“…(19) is strictly valid for rigid particles in three-dimensional (3-D) suspensions [15]. The correspondence shown by Douglas and Garboczi also predicts that the critical exponent is 4/3 for 2-D suspensions [15], a prediction that is confirmed by experiments on thin films of oil containing small spherical particles [16]. Although there is some question in the literature about its universality, the value of 2 has been shown to be, at the very least, a good approximation of the exponent for a wide range of 3-D suspensions [3,[17][18][19][20]26].…”

Section: Approach Based On Critical Phenomenamentioning

confidence: 86%