Floating cylinders on carbonated water realize Lorenz attractor via bubble-driven instability

Cylinders of varying radii and mass distributions were floated on carbonated water in controlled tanks. Bubble accumulation under the body creates torque; rotation then sheds bubbles at the air interface. High-speed imaging captured rolling, periodic oscillation, aperiodic motion, and intermittent capsizing as gas concentration and offset were varied. A continuum model for bubble density, reduced via Galerkin projection, maps directly onto the Lorenz equations with an added slow drift from continuous degassing.

The setup sweeps a full bifurcation diagram autonomously as CO2 escapes, without external parameter tuning. Small center-of-mass shifts stabilize fixed points that would otherwise yield chaos, a result consistent with prior analyses of asymmetric Lorenz variants. This physical analog offers continuous, observable trajectories unavailable in numerical integrations or electronic circuits.

Related work includes Strogatz's treatment of the Lorenz system and experimental fluid realizations such as the 1990s salted-water convection cells. The bubblewheel adds accessibility and slow autonomous parameter drift, opening routes to study noise-induced transitions and control strategies relevant to data assimilation in chaotic engineering systems.

Next steps include coupling multiple bodies and adding active feedback to test chaos-control theorems in real time, with potential applications in microfluidic mixing and autonomous sensor platforms.