Two-dimensional wavelet analysis on organized motions and mean flow structures in an open-channel cavity flow
Hitoshi Miyamoto, Daisuke YAMANAKA · Journal of the Visualization Society of Japan · 2004
Organized motions and mean flow structures in an open-channel cavity flow are examined by using wavelet transforms. Experimental data of velocity vectors are obtained by the particle image velocimetry (PIV). The multiresolution approximation (MRA) is used to extract velocity components of the organized turbulence and the mean flow structures from the PIV data. Distributions of an instantaneous Reynolds stress of the organized turbulence are analyzed by using the two-dimensional continuous wavelet transform (2D-CWT) to detect spatial scales and locations of the organized motions. Characteristics of the organized motions and their dependence on the hydraulic parameters, such as Reynolds number and Froude number, are discussed in detail.