Continuous wavelet analysis of coherent str ( } 1 ) 7 3 , / " 1 cfures

We perform an analysis of planar cuts through three-dimensional turbulent fields (planar channel flow and mixing layer) using the 2D continuous wavelet transform. We propose two new diagnostics: (a) a measure of intermittency I(r,x), which is the ratio of local energy and average energy at a given scale r. (b) a local Reynolds number, defined on the local velocity contribution at a given scale, computed from the wavelet transform of the three velocity components, the scale of the transform, and molecular viscosity; this gives a representation of the local non-linearity of the flow viewed in both space and scale. We find, for all the analyzed flows, strong small-scale intermittency located in the ejection regions for the channel flow and in the vortex core for the mixing layer.