Spatial and temporal turbulent velocity and vorticity power spectra from   sound scattering
  By performing sound scattering measurements with a detector array consisting of 62 elements in a flow between two counter-rotating disks we obtain the energy and vorticity power spectra directly in both spatial and temporal domains. Fast accumulated statistics and large signal-to-noise ratio allow to get high quality data rather effectively and to test scaling laws in details. 
Shahar Seifer and Victor Steinberg