Placing a heavier fluid on the top of a lighter one leads to the Rayleigh-Taylor instability. The main goal of the project is to understand how the onsert and development of the instability may be controlled by fine tuning of the rheological properties of the two fluids. This ongoing project combines table top experiments and numerical simulations using the Gerris flow solver developed by Dr. Stephane Popinet.
The animated sequence of images gives a flavour of what happens when the top fluid is strongly shear thinning (a power law index n=0.45) and the bottom fluid is a Newtonian fluid with a viscosoity roughly ten times smaller than the consistency of the top fluid.