We report on observations of a free-Shercliff-layer instability in a Taylor-Couette experiment using a liquid metal over a wide range of Reynolds numbers, Re∼10(3)-10(6). The free Shercliff layer is formed by imposing a sufficiently strong axial magnetic field across a pair of differentially rotating axial end cap rings. This layer is destabilized by a hydrodynamic Kelvin-Helmholtz-type instabi...

We consider the stability of a configuration consisting of a vertical magnetic field in a planar flow on elliptical streamlines in ideal hydromagnetics. In the absence of a magnetic field the elliptical flow is universally unstable (the “elliptical instability”). We find this universal instability persists in the presence of magnetic fields of arbitrary strength, although the growthrate decreas...

Aims. To investigate the stability and angular momentum transport by the strato-rotational instability in the nonlinear regime. Methods. The hydrodynamic compressible equations are solved in a cartesian box in which the outer cylinder is embedded. Gravity along the rotation axis leads to density stratification. No-slip boundary conditions are used in the radial direction, while free-slip condit...

We combine experiments with simulations to investigate the fluid-structure interaction of a flexible helical rod rotating in a viscous fluid, under low Reynolds number conditions. Our analysis takes into account the coupling between the geometrically nonlinear behavior of the elastic rod with a nonlocal hydrodynamic model for the fluid loading. We quantify the resulting propulsive force, as wel...

N.A. Tahir1, A. Shutov2, I.V. Lomonosov2, A.R. Piriz3, J.G. Wouchuk3, Th. Stöhlker1, and C. Deutsch4 1GSI, Darmstadt, Germany; 2IPCP, Chernogolovka, Russia; 3UCLM, Ciudad Real, Spain; 4LPGP, University Paris–Sud, Orsay, France Richtmyer–Meshkov (RM) instability in solids including the influence of the constitutive properties has previously been studied analytically [1]. This problem is of parti...

Three-dimensional (3D) transport within geophysical vortices (e.g. ocean eddies) is important in understanding processes at a variety of scales, ranging from plankton production to climate variability. 3D transport can be affected by hydrodynamic instabilities of geophysical vortices; however, how the insta-bilities affecting 3D transport is not clear. Focusing on barotropic, inertial and 3D in...

A new transverse mode in a two-stream magnetized quantum plasma is studied by means of a quantum hydrodynamic model, under non-relativistic and ideal Fermi gas assumptions. It is found that Fermi pressure effects induce a minimum cutoff wavelength for instability, unlike the classical case which is unstable for larger wavenumbers. The external magnetic field is also shown to produce a stabilizi...

Semiflexible polymers subject to hydrodynamic forcing play an important role in cytoskeletal motions in the cell, particularly when filaments guide molecular motors whose motions create flows. Near hyperbolic stagnation points, filaments experience a competition between bending elasticity and tension and are predicted to display suppressed thermal fluctuations in the extensional regime and a bu...