Search

We present an entropic version of the lattice Boltzmann pseudo-potential approach for the simulation of multiphase flows. The method is shown to correctly simulate the dynamics of impinging droplets on hydrophobic surfaces and head-on and grazing collisions between droplets, at Weber and Reynolds number regimes not accessible to previous pseudo-potential methods at comparable resolution. [ABSTRACT FROM AUTHOR]

We provide numerical evidence of the transition from rank-ordered trains of internal solitary waves (ISWs) to multi-humped packets. We ascribe such peculiar and unexplored dynamics to the emergence of a long-range influence among waves, mediated by the hydrodynamic conditions developing in the wake of each ISW and promoting acceleration of the trailing waves. Both the train during the transition and its final multi-humped configuration share hydrodynamic features which are consistent with the recently proposed theory of ISWs propagating through moving stratified environments. [ABSTRACT FROM AUTHOR]

In this paper, we numerically investigate the breakup dynamics of droplets in an emulsion flowing in a tapered microchannel with a narrow constriction. The mesoscale approach for multicomponent fluids with near contact interactions is shown to capture the deformation and breakup dynamics of droplets interacting within the constriction, in agreement with experimental evidence. In addition, it permits us to investigate in detail the hydrodynamic phenomena occurring during breakup stages. Finally, a suitable deformation parameter is introduced and analyzed to characterize the state of deformation of the system by inspecting pairs of interacting droplets flowing in the narrow channel. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate that vertically vibrating a plate in a cornstarch suspension causes the suspension to vigorously ratchet up the plate. We show that this is a necessary consequence of the fact that cornstarch inwater is shear thickening: when the plate moves up it opposes gravity and so the fluid stiffens; when it moves down itworks with gravity and so the fluid flows. This produces asymmetric ratcheting that opposes gravity. We find several unusual states that result in this simple experimental system, and we reproduce the essential effect in two different numerical simulations. [ABSTRACT FROM AUTHOR]