Abstract
Turbulent structures in the mixing layer between the main-channel and the concave are analyzed using wavelet transforms. The flow is measured by a particle image velocimetry. The continuous wavelet transform of the velocities successfully detects the characteristics of the large-scale vortices along the mixing layer, such as the spatial scale, frequency, advection velocity and occurrence interval. The joint probability distribution of the scale and the frequency shows that there is a linear relationship between them. Then, the longitudinal and vertical amounts of the kinetic energy is clearly decomposed into the components according to the respective frequencies by using the multiresolutional analysis. The frequency ranges are classified into three groups that are characterized by the energy distributions of the components. These results strongly support the applicability of wavelet transforms to this flow.
