Fuck Yeah Fluid Dynamics

When two liquid jets collide, they can form an array of shapes ranging from a chain-like stream or a liquid sheet to a fishbone-type structure of periodic droplets. This series of images show the collision of two viscoelastic jets—in which polymer additives give the fluids elasticity properties unlike those of familiar Newtonian fluids like water. The jet velocities increase with each image, changing the behavior from a fluid chain (a and b); to a fishbone structure (c and d); to a smooth liquid sheet (e); to a fluttering sheet (f and g); to a disintegrating ruffled sheet (h), and finally a violently flapping sheet (i and j). The behavior of such jets is of particular interest in problems of atomization, where it can be desirable to break an incoming stream of liquid up into droplets as quickly as possible. (Photo credit: S. Jung et al.)