Transport processes in fractals III. Taylor despersion in two examples of fractal capillary networks

Abstract Taylor dispersion is studied on a tree and on a Sierpinski gusket. On a tree, the exact expression of the probability is obtained, from which the m-adic global moments are derived; various temporal behaviours arc then exhibited, as they depend upon a geometrical parameter. On a Sierpinski gasket, numerical calculations are performed, the flow “field” is first discussed; Taylor dispersion is analysed with the help of the two first moments; the influence of the finite character of the network is clearly pointed out; the main conclusion is that Taylor dispersion is almost completely independent upon the flow field even for a low number of generations.

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