Wavelet Analysis to Detect Multi-scale Coherent Eddy Structures and Intermittency in Turbulent Boundary Layer
نویسنده
چکیده
In the early stage of turbulence study, turbulent flow was deemed fully random and disorder motions of fluid particles. Thus physical quantity describing turbulence was considered as the composition of random fluctuations in spatial and temporal field. Reynoldsう1895えdivided the turbulent field into mean field and fluctuating field and then theories and methods based on statistics for turbulence research were developed. Kolmogorov[1] analyzed the relative motion of fluid particles in fully development isotropic and homogeneous turbulent flow based on random field theory and presented the concept of structure functions, which described the relative velocity of two fluid particles separated by distance of l , to investigate the statistical scaling law of turbulence:
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