Necking after extensional filament stretching of complex fluids and soft solids
نویسندگان
چکیده
منابع مشابه
Filament-stretching Rheometry of Complex Fluids
■ Abstract Filament-stretching rheometers are devices for measuring the extensional viscosity of moderately viscous non-Newtonian fluids such as polymer solutions. In these devices, a cylindrical liquid bridge is initially formed between two circular end-plates. The plates are then moved apart in a prescribed manner such that the fluid sample is subjected to a strong extensional deformation. As...
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We study the linear instability with respect to necking of a filament of polymeric fluid undergoing uniaxial extension. Contrary to the widely discussed Considère criterion, we find the onset of instability to relate closely to the onset of downward curvature in the time (and so strain) evolution of the zz component of the molecular strain, for extension along the z axis. In establishing this r...
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ژورنال
عنوان ژورنال: Journal of Non-Newtonian Fluid Mechanics
سال: 2017
ISSN: 0377-0257
DOI: 10.1016/j.jnnfm.2017.06.009