Position-space renormalization group

In order to be useful in practice, the effective transport coefficients have to be determined for a porous medium of given morphology. For this purpose, a broad class of methods is available (for an overview, see [191]). A very straightforward approach is to assume a periodic structure of the porous medium and to compute numerically the flow, concentration or temperature field in a unit cell [117]. Two very general and powerful methods are the effective-medium approximation (EMA) and the position-space renormalization group method. 

As a second method to determine effective transport coefficients in porous media, the position-space renormalization group method will be briefly discussed. 

Although in principle a powerful and elegant method, the position-space renormalization group method yields very complex expressions for the renormalized... 

Berker AN, Wortis M. Blume-Emery-Griffiths-Potts model in two dimensions phase diagram and critical properties from a position-space renormalization group. Physical Review B. 1976 14 4946-4963. DOI 10.1103/PhysRevB.14.4946. 

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