In a recent study lead by UBC Mechanical Engineering Professor Gwynn Elfring, the team used large-scale hydrodynamic simulations to demonstrate how external shear forces applied to an active fluid being stirred influence – and even reduce – the long-time dynamics of moving particles as they diffuse through the liquid. They identified a simple mechanism to explain the interplay observed between the external force from the action of stirring and the internal forces made by the moving particles in the liquid, and how they may work against each other. Their study explains a general but unexpected feature of fluids that have an underlying microstructure and internal persistence, and may suggest new ways to direct how particles in fluids are transported – findings which could open up new techniques for applications like developing advanced materials and medical technology.
Read “Nonmonotonic Diffusion in Sheared Active Suspensions of Squirmers” in Physical Review Letters: https://doi.org/10.1103/54qq-1s51.
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