Comparison of wavelet analysis with velocity derivatives for detection of shear layer and vortices inside a turbulent boundary layer

0370298 - ÚT 2012 RIV GB eng J - Journal Article
Kellnerová, Radka - Kukačka, Libor - Jurčáková, Klára - Uruba, Václav - Jaňour, Zbyněk
Comparison of wavelet analysis with velocity derivatives for detection of shear layer and vortices inside a turbulent boundary layer.
Journal of Physics: Conference Series. Roč. 318, - (2011), s. 1-10. ISSN 1742-6588. E-ISSN 1742-6596.
[European Turbulence Conference /13./. Warsaw, 12.09.2011-15.09.2011]
Institutional research plan: CEZ:AV0Z20760514
Keywords : Wavelet analysis * street canyon * POD
Subject RIV: DG - Athmosphere Sciences, Meteorology
http://iopscience.iop.org/1742-6596/318/6/062012?fromSearchPage=true

Detection of highly energetic structure in the turbulent flow can be easily done by wavelet analysis, especially with Morlet function as a mother wavelet for detection of repetitious low-frequency structures and Mexican hat for detection of vortices. Since wavelet analysis can be simply applied on one-point measurement, the better understanding of its meaning is welcome. In this project, turbulent boundary layer was investigated with focus on intermittent dynamics. PIV snapshot were used for comparison with Wavelet analysis results, since PIV was performed with high sample frequency (500 Hz). Instantaneous snapshots of velocity and vorticity were studied also by POD and spectra of particular expansion coefficients were computed. Vorticity from planar velocity vectors was used as a suitable methods for recognition of strongly deformed streamlines.
Permanent Link: http://hdl.handle.net/11104/0204140