Struktury koherentne osiowo-symetrycznej strugi swobodnej

The paper presents an analysis of coherent structures existing in the initial region of the axisymrnetric free jet. The results of the experiment support the thesis, that the laminar-turbulent transition results in the existence of three different forms of organised vorticity. Coherent structures resulting either from the instability of free shear-layer of from the jet-column instability constitute a link between the perfectly organised laminar motion and the fully chaotic turbulent flow.