Organized structure dynamics in a turbulent round jet

摘要

The dynamics of large scale azimuthally-coherent structures obtained in a high Reynolds-number axisymmetric mixing layer are presented. The structure dynamics are obtained by application of the Proper Orthogonal Decomposition (POD) to an ensemble of realizations of the streamwise velocity field obtained from 138 probes located 3 diameters downstream of the nozzle exit. The velocity field is measured at all 138 positions simultaneously, making it possible to obtain the instantaneous coefficients of the POD modes as well as to extract the large scale structure.