Manchester Centre for Nonlinear Dynamics
Features
A perforated column can buckle in a complex way when compressed, due to interactions between deformations over the lengthscale of the whole column, bending of the thin ligaments that separate the perforations, and nonlinearity of material response. Read more...
Sinuous instability of a confined jet
Left: Passive tracers (shown as streaks) in a confined turbulent momentum jet; middle: corresponding velocity field (arrows) and vorticity field (background) measured using particle image velocimetry; right: schematic of the self-similar unstable sinuous core and alternating side vortices.
Numerical bifurcation tracking.
Contours of axial velocity for the flow past a cylindrical obstacle in a channel (top). A Hopf bifurcation occurs at Re ≈ 92, and the contours of the axial velocity for the critical eigenfunction (bottom) illustrate the complex downstream structure that must be resolved to accurately determine the location of the bifurcation.
Bubbles propagating through expansions and contractions:
Semi-infinite and finite bubbles, propagating through a fluid filled channel of varying geometries. These have applications in microfl'>Read more...
Viscous fingering under a cellophane sheet.
Air is injected at constant flow rate into an oil-filled elastic cell, coupling a fingering instability to the wrinkling of the cellophane sheet.