Suppression of the instability of rotating flows

The possibilities of controlling the instability that develops in the form of traveling azimuthal waves in a spherical Couette flow are experimentally investigated. It is found that the effect of the periodic modulation of the rotational velocity of the inner sphere on the traveling azimuthal waves can lead to their suppression, with the instability associated with traveling azimuthal waves, including those with a change in the wavenumber, being restored when the modulation is turned off. The possibility of long-term preservation of a stable steady flow after the end of modulation–at least for 50 min or for two thousand revolutions of the inner sphere, which is four times higher than the time of transient processes in a steady flow–is found.