"Wavelet statistics and the near-field structure of coaxial jets"

by
Lewalle, J, Petagna, P. and Buresti, G.

ABSTRACT

In this study, we examine the dynamical role of the flow structures in the near field of a large-Reynolds-number coaxial jet. The experimental data consist of 2-component laser-Doppler and hot-wire anemometry records. Some flow statistics are obtained by conventional methods, but the intermittent active structures are identified by using the spectral/temporal discrimination capability of wavelet transforms. We focus on the size, intermittency and amplitude of these structures, and on their role in the instantaneous and mean radial flux of momentum. In contrast to the cross-spectra, the wavelet approach provides a very clear picture of the relevant length scales.