Vortex Shedding in Confined Swirling Flow of Polymer Solutions

Axisymmetric vortex breakdown Part 1. Confined swirling flow

A comparison between the experimental visualization and numerical simulations of the occurrence of vortex breakdown in laminar swirling flows produced by a rotating endwall is presented. The experimental visualizations of Escudier (1984) were the first to detect the presence of multiple recirculation zones and the numerical model presented here, consisting of a numerical solution of the unstead...

Hierarchical Vortex Regions in Swirling Flow

We propose a new criterion to characterize hierarchical two-dimensional vortex regions induced by swirling motion. Central to the definition are closed loops that intersect the flow field at a constant angle. The union of loops belonging to the same area of swirling motion defines a vortex region. These regions are disjunct but may be nested, thus introducing a spatial hierarchy of vortex regio...

Numerical Simulation of a Confined Swirling Flow in a Model Gas Turbine Combustor

Sidewall boundary layer instabilities in confined swirling flow †

We examine enclosed swirling transitional and turbulent flows in a cylindrical vessel, driven by a single rotating endwall. The cylinder height:radius ratio H/R = 1 was chosen explicitly to preclude the possibility of vortex breakdown on the cylinder axis, thus concentrating attention on the behaviour of the cylindrical sidewall boundary layers. Over a range of Reynolds numbers above Re = ΩR2/ν...

Confined flow of polymer blends.

The influence of confinement on the steady-state morphology of two different emulsions is investigated. The blends, made from polybutene (PB) in polydimethylsiloxane (PDMS) and polybutadiene (PBD) in PDMS, are sheared between two parallel plates, mostly with a standard gap spacing of 40 microm, in the range of shear rates at which the transition from "bulk" behavior toward "confined" behavior i...