| Abstract: | A motion of a vortex ring in a stratified fluid is accompanied by associated disturbances which, in the schlieren visualization
in the field of a horizontal density gradient, have the shape of a symmetric four-petal configuration. The criterion of the
existence of the disturbances is the Froude number Fr based on the motion velocity and the vertical vortex size. On the range
Fr > 1, the disturbances are stable with respect to the variation of themotion regime and the distortion of the vortex shape.
For Fr < 1 the disturbances disappear. Computer processing of the schlieren photographs showed that the experimental spatial
dependences of the disturbance amplitude are close to the functions describing the distribution of the vertical velocity component
in the inviscid flow past a sphere. |
