"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.