Resources

Author(s): Damien P. Huet, Antoine Morente, Guodong Gai, and Anthony Wachs We investigate the inertial and noninertial dynamics of three-dimensional elastic capsules flowing through a square channel presenting a sharp corner. The channel Reynolds number Re ranges from 0.01 to 50 and the Capillary number Ca, which measures the ratio of the viscous and elastic stresses, ranges from 0.075 to 0.35. We report trajectory, surface area, velocity and...

Author(s): Thomas J. Lambert, Bojan Vukasinovic, and Ari Glezer The reciprocal coupled interactions between a forebody gimbaled axisymmetric bluff body, free to precess in pitch, yaw, and roll, and the body’s near wake are exploited for prescribing its attitude using fluidic actuation. It was shown that closed-loop control of pitch and yaw can significantly attenuate the inherent model’s baseline oscillations by more than 80%, or the control could...

Author(s): Yves-Marie Ducimetière, Edouard Boujo, and François Gallaire We consider flows subject to a steady symmetry-breaking bifurcation and forced by a weak noise acting on a slow timescale. By employing a multiple-scale weakly nonlinear expansion technique, we derive a stochastically forced Stuart-Landau equation for the dominant symmetry-breaking mode. The probability density function of the solution, and of the escape time from one attractor...

Author(s): Nghia Le, Casey M. Miller, Julianna S. Detrick, Cameron R. Lodi, Kevin A. Mitchell, and Thomas H. Solomon Self-propelled (active) particles in laminar fluid flows are blocked by one-way barriers called “swimming invariant manifolds” (SwIMs). The SwIM theory is a generalization of manifold approaches previously applied to the mixing of passive tracers. We verify the blocking behavior of SwIMs experimentally for algae swimming in a vortex...

Author(s): Izumi Saito, Takeshi Watanabe, and Toshiyuki Gotoh The turbulent transport of small particles (dust particles, cloud droplets, etc.) can be viewed macroscopically as a problem of passive scalar turbulence with extremely high Schmidt numbers. To investigate the spectrum of a passive scalar carried by such particles, we conducted Lagrangian particle simulations in homogeneous isotropic turbulence. The scalar variance spectrum obeys the...

Author(s): Hassan El Itawi, Benjamin Lalanne, Subhadarshinee Sahoo, Emmanuel Cid, Gladys Massiera, Nathalie Le Sauze, and Olivier Masbernat Substituting a centrifugal field to gravity makes possible the study of the dynamics of rising deformable drops in another immiscible liquid, keeping free from contamination of the interface. In this experiment, impurities do not have time to adsorb during the very short residence time due to the strong acceleration...

Author(s): Lennard Miller, Bruno Deremble, and Antoine Venaille We unveil a gyre turbulence regime within a two-dimensional wind-driven ocean model, where energy dissipation becomes independent of fluid viscosity. This anomalous dissipation is driven by a vigorous two-dimensional vortex gas overlaying a low energy western-intensified gyre, shedding light on the effect of boundary instabilities in disrupting the inverse energy cascade. [Phys...