1 Biocomplexity, The Niels Bohr Institute, Faculty of Science, Københavns Universitet2 Sendai National College of Technology3 Kyushu University, Department of Chemistry4 Biocomplexity, The Niels Bohr Institute, Faculty of Science, Københavns Universitet
We report experimental observations of the shear thickening oscillation, i.e. the spontaneous macroscopic oscillation in the shear flow of severe shear thickening fluid. Using a density-matched starch-water mixture, in the cylindrical shear flow of a few centimeters flow width, we observed that well-marked vibrations of frequency around 20 Hz appear via a Hopf bifurcation upon increasing externally applied shear stress. The parameter range and the frequency of the vibration are consistent with those expected by a simple phenomenological model of the dilatant fluid.