The presentation focuses on the development of macroscopic models of flow indouble-porosity soils by the method of asymptotic homogenization. This methodallows to derive the macroscopic models from the description of physicalprocesses at the local scale, without any a priori assumptions on the finalform of the model. The domain of validity of the model is precisely defined bythe analysis of dimensionless numbers governing the flow. The effectivemacroscopic conductivity of the medium is defined as the function of localconductivity and geometry of the medium. For the non-equilibrium flow oneobtains a single macroscopic equation with integral source term describing thewater transfer between two regions.
Several numerical examples are presented. The results obtained byhomogenization are compared to the phenomenological model of Gerke and vanGenuchten and to the fine scale reference solution, where the heterogeneousstructure of the medium is explicitly represented. The simulations show thatthe model obtained by homogenization gives results close to the referencesolution and correctly estimates the effective parameters.
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