2021/01/28 by Carlos Villarroel, Gustavo Düring, Villarroel, Carlos +1 · 2 citations
Materials Science · Physics and Astronomy · #Material Dynamics and Properties #Pickering emulsions and particle stabilization #Theoretical and Computational Physics
paper · pdf · doi:10.48550/arxiv.2101.12345
In the last decade many research efforts have been focused on understanding\nthe rheology of disordered materials, and several theoretical predictions have\nbeen put forward regarding their yielding behavior. Nevertheless, not many\nexperiments nor molecular dynamics simulations were dedicated to testing those\ntheoretical predictions. Here we use computer simulations to study the yielding\ntransition under two different loading schemes: standard simple shear dynamics,\nand self-propelled, dense active systems. In the active systems a yielding\ntransition is observed as expected, when the self-propulsion is increased.\nHowever, the range of self-propulsions in which a pure liquid regime exist\nappears to vanish upon approaching the so-called "jamming point" at which\nsolidity of soft-sphere packings is lost. Such an "active yielding" transition\nshares similarities with the generic yielding transition for shear flows. A\nHerschel-Bulkley law is observed in both loading scenarios, with a clear\ndifference in the critical scaling exponents between the two, suggesting the\nexistent of different universality classes for the yielding transition under\ndifferent driving conditions. In addition, we present direct measurements of\nlength and time scales for both driving scenarios. A comparison with\ntheoretical predictions from recent literature reveals poor agreement with our\nnumerical results.\n