The
Richtmyer-Meshkov instability occurs when two fluids of differing density are hit by a
shock wave. The animation above shows a cylinder of denser gas (white) in still air (black) before being hit with a Mach 1.2 shock wave. The cylinder is quickly accelerated and flattened, with either end spinning up to form the counter-rotating
vortices that dominate the instability. As the vortices spin, the fluids along the interface shear against one another, and new, secondary instabilities, like the wave-like
Kelvin-Helmholtz instability, form along the edges. The two gases mix quickly. This instability is of especial interest for the application of
inertial confinement fusion. During implosion, the shell material surrounding the fuel layer is shock-accelerated; since mixing of the shell and fuel is undesirable, researchers are interested in understanding how to control and prevent the instability. (Image credit:
S. Shankar et al.)
