Stress fluctuations and shear thickening in dense granular suspensions
نویسندگان
چکیده
منابع مشابه
Localized stress fluctuations drive shear thickening in dense suspensions.
Dense particulate suspensions exhibit a dramatic increase in average viscosity above a critical, material-dependent shear stress. This thickening changes from continuous to discontinuous as the concentration is increased. Using direct measurements of spatially resolved surface stresses in the continuous thickening regime, we report the existence of clearly defined dynamic localized regions of s...
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Suspensions are of wide interest and form the basis for many smart fluids. For most suspensions, the viscosity decreases with increasing shear rate, that is, they shear thin. Few are reported to do the opposite, that is, shear thicken, despite the longstanding expectation that shear thickening is a generic type of suspension behaviour. Here we resolve this apparent contradiction. We demonstrate...
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ژورنال
عنوان ژورنال: Journal of Rheology
سال: 2020
ISSN: 0148-6055,1520-8516
DOI: 10.1122/1.5133037