Three-dimensional instability of axisymmetric flow in a rotating disk–cylinder configuration is studied numerically for the case of low cylinders with the height/radius aspect ratio varying between 1 and 0.1. A complete stability diagram for the transition from steady axisymmetric to oscillatory threedimensional flow regime is reported. A good agreement with the experimental results is obtained...

We report that the formation of much reported axial segregation bands in rotating cylinders loaded with different sized particles depends critically on scale and inertia. Specifically, when the ratio, δ, of the diameter of the cylinder to the average diameter of the particles is large, axial bands invariably appear, when δ is small, bands never appear, and between these extremes lies a reversib...

A finite element study of two and three-dimensional incompressible viscoelastic flows in a planar lid-driven cavity and concentric rotating cylinders is presented. The hardware platforms consist of both homogeneous and heterogeneous clusters of workstations. A semi-implicit time-stepping TaylorGalerkin scheme is employed using the message passing mechanism provided by the Parallel Virtual Machi...

Macroscopically, a polymer-stabilized blue phase liquid crystal (BPLC) is assumed to be an optically isotropic medium. Our experiment challenges this assumption. Our results indicate that the optical rotatory power (ORP) of some nano-scale double-twist cylinders in a BPLC composite causes the polarization axis of the transmitted light to rotate a small angle, which in turn leaks through the cro...

The effect of temporal modulation on traveling waves in the flows in two distinct systems of rotating cylinders, both with broken azimuthal symmetry, has been investigated. It is shown that by modulating the control parameter at twice the critical frequency one can excite phaselocked standing waves and standing-wave-like states which are not allowed when the system is rotationally symmetric. We...

Abstract Delaying laminar–turbulent transition in boundary layers is of great interest since the skin-friction coefficient can be reduced by up to one order magnitude. In this experimental research, it shown that counter-rotating cylindrical roughness elements are able delay under realistic flow conditions. Evidence given intermittency, evaluated from hot-film measurements a laminar water chann...

We have previously introduced the parameter as an indicator of stability to m = 2 nonaxisymmetric modes in rotating, self{gravitating, axisymmetric, gaseous ( < 0:34) and stellar ( < 0:25) systems. This parameter can be written as = (ft=2), where t T=jW j, T is the total rotational kinetic energy, W is the total gravitational potential energy, and f is a function characteristic of the topology/...

Concentrated suspensions, composed of solid particles and fluids, are used in many industrial applications. In this paper, we study the effects of temperature on the flow of a concentrated (dense) suspension between two long rotating cylinders. The viscosity of the suspension is assumed to depend on temperature and volume fraction of the solid particles. Based on these concepts, a generalized v...