Number 363 (Story #2), March 23, 1998 by Phillip F. Schewe and Ben Stein
NEW METHODS OF STUDYING TURBULENCE, reported at the APS meeting, have enabled physicists to track in detail for the first time the accelerations of a particle moving through flows with atmospheric-level turbulence (Eberhard Bodenschatz, Cornell, 607- 255-0794), and to cause magnetically trapped electrons to act like fluid particles on a flat surface (Fred Driscoll, UC-San Diego, 619- 534-2498). Bodenschatz described how a light-sensitive diode measured the movements of a particle jiggling through a fluid at up to 200 times the acceleration of gravity. For upcoming experiments, the group has installed a "silicon-strip detector" used in high-energy physics to make up to 100,000 measurements per second of multiple particles in the fluid, the better to study how particles that are initially close together move apart in a very turbulent flow such as a volcanic eruption. Meanwhile, Driscoll investigated turbulence by using a strong magnetic field to trap a cigar-shaped column of a billion electrons. Viewed from the end of the column, the electrons moved like fluid particles on a 2D surface. Intriguingly, turbulent flows of these electrons spontaneously settled into "vortex crystals," geometric patterns of whirlpool-like eddies that stayed frozen in place. (Also see lay language papers by Bodenschatz and Driscoll.)
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