PICS Seminar: “Computational fluid dynamics for slurry rheology in flow battery and underlying drag-reduction mechanisms in turbulent flow control”

Email jnespos@seas.upenn.edu for the Zoom link.

This talk will start by introducing diverse fluid-mechanics research conducted in the Park research group, including complex fluids, electrokinetics, biofluids, transition-to-turbulence, and turbulent flow. I will then focus on two projects at very different flow regimes. For both projects, the modeling, analysis, and computation will be presented along with their engineering applications. The first project is dedicated to a creeping flow or Stokes flow, where dynamics and rheology of highly conductive particle suspensions in an electric field are investigated to help design flow battery slurries. Notably, the negative particle pressure is found to arise at high concentrations, which could be considered a first-of-its-kind in such particle systems. The second project is dedicated to a high-speed flow or turbulent flow, where three flow-control methods are investigated to elucidate their underlying drag-reduction mechanisms. These methods include imposing an external body force, adding long-chain polymers, and utilizing slip surfaces. A temporal analysis based on high- and low-drag periods is employed, showing that the polymer and slip methods exhibit a similar mechanism, while the body force method is different. I will conclude by providing the implications of these different drag-reduction mechanisms.