Time-resolved proper orthogonal decomposition of the near-field flow of a round jet measured by dynamic particle image velocimetry

In this study time-resolved proper orthogonal decomposition (POD) is proposed for the new technique of dynamic (digital) particle image velocimetry (DPIV), and applied to study the coherent structures at the near field of a round jet flow. Time-resolved POD is computed in the radial direction, the axial direction and the temporal domain, in which the turbulence can be easily measured by DPIV. As a result, large-scale vortical structures and their spatial and temporal evolution at the round jet mixing layer are uncovered.