The effects of capillary forces on the flow properties of glass particle suspensions in mineral oil

Abstract

The effect of water on the flow behavior of glass microspheres dispersed in mineral oil was investigated for various levels of water, particle volume fractions, and particle sizes. The addition of small amounts of water leads to large increases in viscosity due to the formation of water bridges between particles that give rise to capillary forces between the particles. The capillary forces between the particles also make the flow profile highly shear-thinning across the range of particle volume fractions that were studied (0.10 to 0.25). The presence of water leads to a significant effect of particle size, and the viscosity of dispersion goes through a maximum as the amount of water is increased. Two hydrophobic surfactants, Span 80 and Arquad 2HT, were found to reduce the viscosity of the dispersions with added water, but the mechanism and extent of viscosity reduction differed.

Preparation and yielding behavior of pendular network suspensions

“…The most familiar example is of sand which, when wetted with small amounts of water, develops sufficient yield stress to allow construction of elaborate sand castles [1][2][3][4]. The same is true for particles-in-liquid suspensions: Addition of a small amount of a second immiscible liquid can create a network which endows the suspension with a yield stress [5][6][7][8][9][10][11][12][13][14].…”

A comparison of the rheological behavior of hydrate forming emulsions stabilized using either solid particles or a surfactant

“…More challenging exploration and development has 27 emphasized the need to investigate the rheological behavior of hydrates in order to ensure continuous 28 production of crude oil through pipelines especially for solid stabilized emulsions. Therefore, a difference 29 in the rheological behavior of hydrate forming water-in-oil emulsions stabilized using either solid parti- 30 cles (Aerosil R974, fumed silica particles) or a surfactant (Span 80, a non-ionic surfactant) over a range of 31 water cuts is investigated. A rheometer with helical ribbon geometry was used to investigate the 32 rheological behavior of hydrate slurries as opposed to conventional standard geometries.…”

A facile microfluidic strategy for measuring interfacial tension

“…When adopting the same environment temperature, this value agrees well with the reported data. [22][23][24] Moreover, by combining the well-developed microfluidic techniques, we can extend the method to studying dynamic IFT. 9,19,25 To summarize, we demonstrate a facile approach in which in situ IFT measurement is performed in a microfluidic device coupled with a syringe pump and a microscope (the necessary instruments in any microfluidic laboratories).…”