Extraction of a Multiscale Structure of a Turbulent Lobed Jet from PIV Results Using a Vector Wavelet Multiresolution Technique
نویسندگان
چکیده
The wavelet-based vector multiresolution technique was applied to the postprocessing of PIV results for identifying the multiscale turbulent structures of a lobed jet. By analyzing the instantaneous streamlines and vorticity fields of various scales, we obtained important information on the multiscale flow structures. The large-scale vortices or coherent structures with a central scale of a = 15.36 mm were easily extracted from PIV measurement results. The intermediateand small-scale vortices embedded within the large-scale vortices were separated and visualized.
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