Suppression of turbulence in rotational flows

The capabilities of controlling turbulence in a spherical Couette flow have been experimentally investigated. It is shown that, with increasing modulation amplitude of the outer sphere rotation velocity, the turbulence may be suppressed with a transition to laminar flow. The reverse process–the recovery of turbulence–is possible under decreasing amplitude. The destruction and reconstruction of turbulence are established to be accompanied by hysteresis. It is shown that, for small modulation amplitudes, suppression of turbulence is possible only within a narrow frequency band.