Title: Microstructure and thickening of dense suspensions under extensional and shear flows,
Abstract: Dense suspensions are non-Newtonian fluids which exhibit strong shear
thickening and normal stress differences. Using numerical simulation of
extensional and shear flows, we investigate how rheological properties are
determined by the microstructure which is built under flows and by the
interactions between particles. By imposing extensional and shear flows, we can
assess the degree of flow-type dependence in regimes below and above
thickening. Even when the flow-type dependence is hindered, nondissipative
responses, such as normal stress differences, are present and characterise the
non-Newtonian behaviour of dense suspensions.