Simple shear of materials characterized by steady non-monotonous flow curve

摘要: The non-monotonic character of the steady flow curve is a possible explanation for spurious phenomena (wall depletion, yield stress, stick-slip and shear banding) observed in rheological tests complex fluids with unstable internal network structure. In this work, lubricating greases, polyxiloxane cosmetic creams, sensitive magnetic solder pastes are experimentally investigated to detect existence instability region curve. experiments based on simple dynamic performed both linear non-linear regimes. results showed time dependence some discrete preferred values viscosity function. accomplished by numerical simulations generalized Newtonian models non-monotonous correlation between indicate that material always related onset banding structure vicinity walls. qualitatively consistent prove bands location within gap dependent (for given parameters) dynamics flow, respectively initial/boundary conditions.