We report an experimental investigation of various statistical properties ofthe spatial Fourier modes of the vorticity field in turbulent jets for a largerange of Reynolds numbers ($530 \leq R_{\lambda} \leq 6100$). The continuoustime evolution of a spatial Fourier mode of the vorticity distribution,characterized by a well defined wave-vector, is obtained from acousticscattering measurements. The spatial enstrophy spectrum, as a function of thespatial wave-vector, is determined by scanning the incoming sound frequencies.Time-frequency analysis of the turbulent vorticity fluctuations is alsoperformed for different length scales of the flows. Vorticity time-correlationsshow that the characteristic time of a Fourier mode behaves as the sweepingtime. Finally, we report preliminary Lagrangian velocity measurements obtainedusing acoustic scattering by soap bubbles inflated with helium. Gathering avery large number ($\geq 13~10^{6}$) of passages of isolated bubbles in thescattering volume, one is able to compute the Lagrangian velocity PDF andvelocity spectrum. Despite the spatial filtering due to the finite size of thebubble, the latter exhibits a power law with the -2 exponent predicted by theKomogorov theory, over one decade of frequencies.
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