Fractals are objects that display self-similarity or self-affinity over a wide range of scales. Fully developed turbulence indeed consists of a hierarchy of eddies, or scales of various disorders. Thus, this can be one type of fractal. Turbulence can be studied in velocity field. Time series of velocity components are very irregular. Modeling of such velocity fluctuations using Euclidean functions is almost impossible, however, fractal interpolation functions (FIF) can be attractive tools to fulfill this desire. In this study, FIF was used to model more than 200000 time series of velocity fluctuations and Reynolds shear stress in open channel flows. Fractal dimension of velocity fluctuation components and shear stress was calculated using FIF. Fractal dimensions of u', v', and u'v' were found to be 1.615, 1.657, and 1.559, respectively. The relationships of fractal dimension with Froude and Reynolds numbers were also investigated.
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