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http://dx.doi.org/10.5394/KINPR.2008.32.10.777

Flow Field Separating Technique in Bubbly Flow using Discrete Wavelet  

Jo, Hyo-Jae (Division of Shipbuilding & Ocean System Engineering, Korea Maritime University)
Doh, Deog-Hee (Division of Mechanical and Information Engineering, Korea Maritime University)
Choi, Je-Eun (Department of Mechanical Engineering, Nihon University)
Takei, Masahiro (Department of Mechanical Engineering, Nihon University)
Kang, Byung-Yoon (Leading Boat Development)
Publication Information
Journal of Navigation and Port Research / v.32, no.10, 2008 , pp. 777-783 More about this Journal
Abstract
Nowadays wavelet transforms are widely used for the analyses of PIV velocity vector fields. This is bemuse the wavelet provides not only spatial information of the velocity vectors but also of time and frequency domains. In this study, a discrete wavelet trC1f1$form has been applied to real PIV images of bubbly flows. The vector fields obtained by a self-made cross-correlation PIV algorithm were used for the discrete wavelet transform The performances of the discrete wavelet transform is investigated by changing the level of power of discretization. The decomposed images by the wavelet multiresolution showed conspicuous characteristics of the bubbly flows according to the level changes. The high spatial bubble concentrated area could be evaluated by the constructed discrete wavelet transform algorithm, at which high leveled wavelets could play a dominant roles to reveal the flow characteristics.
Keywords
PIV; Discrete wavelet transform; Flow characteristics; Bubbly flow;
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