Rayleigh-Taylor instability is investigated in gases subjected to acceleration due to an expansion wave in a vacuum tube. Stable stratification of two gases is created using a counter-flow system similar to that used in shock tube experiments.  The interface is accelerated by a rarefaction wave generated by puncturing a membrane which separates the test chamber and vacuum chamber, resulting in an acceleration of nearly 2,600g.   The development of the instability can be studied from flat initial conditions as well as for perturbed initial conditions.


Experiments are visualized using shadowgraphy or by planar Mie scattering.  



Rendering of the experimental setup. Left: Shadowgraph system; Right: Entire experimental setup.

The Experimental Fluid Mechanics and Instability Laboratory

Aerospace and Mechanical Engineering Department at University of Arizona