Scale Invariance of Power Spectrum in Sediment Transport Mechanics
Tóm tắt
Flume experiments were carried over a curvilinear mobile sand bed and over a vegetated sand bed to scale the power spectra variation in the longitudinal velocity spectrum of turbulence flow. Instantaneous three dimensional velocities were sampled using an acoustic Doppler velocimeter; sequentially spectral analysis of the filtered velocities is consummated. Results depict that slope of power spectra is varying with the variation of wave number, consequently three different ranges obtained for power spectrum, where spectrum scaling is confined to some particular range according to low, intermediate and high wave numbers.
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