Magnetic fields have been used to produce well aligned nematic liquid crystalline and colloidal crystalline samples of nearly monodisperse tobacco mosaic virus (TMV). Hydrodynamic instabilities induced by reorientation in a magnetic field have been studied in the well aligned nematic liquid crystalline samples.

The nonlinear Rayleigh-Taylor (RT) and Richtmyer-Meshkov (RM) instability are investigated by theoretical models based on singlemode and two-bubble physics at all Atwood numbers (A). A potential-flow treatment of single-mode perturbations shows that the late-time RM single mode velocity decreases as v ∼ λ/t, as well as quantifying a two-bubble overtake interaction (“merger”) analogous to that f...

We apply the Canuto-Goldman (CG) analytical model to turbulence generated by the class of instabilities which have a power-law growth rate. For the case of Rayleigh-Taylor (RT) instability we compare the results of the model with the experiments of Read and Youngs and find reasonable agreement on the scale size of large eddies: they are predicted to be a0% of the mixing length and are at least ...

We review recent developments in the rigorous derivation of hydrodynamic-type macroscopic equations from simple microscopic models: continuous time stochastic cellular automata. The deterministic evolution of hydrodynamic variables emerges as the "law of large numbe~s," which holds with probability one in the limit in which the ratio of the microscopic to the macroscopic spatial and temporal sc...

The axisymmetric linear stability of the Taylor-Couette flow with an azimuthal magnetic field is considered. It is shown that a flow with the combination of a linearly unstable rotation and a linearly unstable azimuthal magnetic field can be linearly stable. The flow stabilization takes place for both ideal and dissipative flows. For dissipative flow the stabilization exists only for a combinat...

The effect of eccentricity on absolute instabilities (AI) in the Taylor–Couette system with pressure-driven axial flow and fixed outer cylinder is investigated. Five modes of instability are considered, characterized by a pseudo-angular order m, with here |m| 6 2. These modes correspond to toroidal (m = 0) and helical structures (m 6= 0) deformed by the eccentricity. Throughout the parameter ra...

We observe powder "droplets" forming when tapping repeatedly a horizontal flat plate initially covered with a monolayer of fine powder particles. Starting from a simple model involving both the air flow through the porous cake and avalanche properties, we set up an analytical model which satisfactorily fits the experimental results. We observe a close analogy between the governing equations of ...

Scaled experiments on the nonlinear evolution of the RayleighTaylor (RT) and Richtmyer-Meshkov (RM) instabilities are described under a variety, of conditions that occur in nature. At high Reynolds number, the mixi,ng layer grows self-similarly aiAgt* for a constant acceleration (g), and as a power law t*’ 1 for impulsive accelerations US(t) at low and high Mach numbers. The growth coefficients...

The objectives of our research are to improve our understanding of the mechanisms underlying the formation of complex spatio-temporal patterns in systems that are driven outside of thermodynamic equilibrium, to characterize the macroscopic properties of such states, and to apply the methodology to situations of interest in fluid physics and engineering. Current research focuses on pattern forma...

We study the stability of cylindrical Taylor-Couette flow in the presence of azimuthal magnetic fields, and show that one obtains nonaxisymmetric magnetorotational instabilities, having azimuthal wave number m=1. For Omega{o}/Omega{i} only slightly greater than the Rayleigh value (r{i}/r{o}){2}, the critical Reynolds and Hartmann numbers are Re{c} approximately 10{3} and Ha{c} approximately 10{...