Self-Organized Traveling Chemo-Hydrodynamic Fingers Triggered by a Chemical Oscillator

Pulsatile chemo-hydrodynamic patterns
due to a coupling between
an oscillating chemical reaction and buoyancy-driven hydrodynamic
flows can develop when two solutions of separate reactants of the
Belousov–Zhabotinsky reaction are put in contact in the gravity
field and conditions for chemical oscillations are met in the contact
zone. In regular oscillatory conditions, localized periodic changes
in the concentration of intermediate species induce pulsatile density
gradients, which, in turn, generate traveling convective fingers breaking
the transverse symmetry. These patterns are the self-organized result
of a genuine coupling between chemical and hydrodynamic modes.