Voskoboinick A. The formation of the coherent vortical structures in the swirling streams and cavities

The special areas of the formation and development of the coherent vortical structures in the swirling streams are revealed by means of the different methods of the visualization. Hot-wire anemometrical measurements of the kinematical characteristics of the stream in these areas were planned and carried out. The integral and spectral characteristics of the wall vortical stream along the vortical chamber are obtained. The location and rotation frequency of the external zigzag stream and the internal tornado-like vortex are registered in the dead-end zone of the chamber. The formation and development of the large- and small-scale vortical structures is revealed in the hemicylindrical and hemispherical cavities. The areas of braking of the stream are registered in front of the cavity at laminar and turbulent flows. The scales, rotation frequencies, circulation of quasi-stable coherent large-scale vortexes in the cavities and frequencies of its break up outside are found. Distinctive features in the frequency and wave spectra of the velocity fluctuations in the form of discrete peaks are registered and physically proved. A number of methods and ways of the passive control of the coherent vortical structures, its scales, the break up and rotation frequencies in the vortical chamber and cavities of the different sizes and geometrical forms are investigated.