The movie below shows the results from an experimental measurement of the flow within a large Rayleigh-Bénard cell.
Tiny (380 µm) helium-filled soap bubbles were illuminated from above by an array of high-power LEDs and imaged from different viewing directions by six cameras which recorded the projections of the bubble system at a rate of 30 Hz.
Using the Shake-the-Box method, which enables Lagrangian particle tracking at high particle image densities, the particle trajectories were reconstructed. More than 550,000 bubbles could be tracked instantaneously, revealing the flow within the cell.
With the support of LaVision's hard- and software, these exemplary results were obtained that illustrate the beauty of the induced turbulent flow and the wealth of the data gathered.