We report experimental observation of the shear thickening oscillation, i.e.
the spontaneous macroscopic oscillation in the shear flow of severe shear
thickening fluid. The shear thickening oscillation is caused by the interplay
between the fluid dynamics and the shear thickening, and has been predicted
theoretically by the present authors using a phenomenological fluid dynamics
model for the dilatant fluid, but never been reported experimentally. Using a
density-matched starch-water mixture, in the cylindrical shear flow of a few
centimeters flow width, we observed strong vibrations of the frequency around
20 Hz, which is consistent with our theoretical prediction.Comment: 4pages, 5 figure