Image by P. Vorobieff/UNM
A mosaic of three images shows the evolution of a planar cross-section of a sulfur hexafluoride (SF6) gas column surrounded by air and impulsively accelerated by a shock (blast) wave. The image extent in the vertical direction is 16 mm, the Mach number of the shock is 1.7, which corresponds to shock front speed of about 560 m/s . The images were captured with a digital SLR camera and visualize laser-induced fluorescence in acetone pre-mixed with SF6 (1% by volume). Actual color of the fluorescence is shown unaltered. Flow direction is from right to left. The images were taken 50, 100, and 150 microseconds after the shock. This mechanism of shock-driven vortex formation is important for a number of practical problems, from inertial confinement fusion to supernova explosions.
This research is sponsored by the U.S. National Nuclear Security Agency (NNSA).