# Bingham flow in porous media with obstacles of different size

By using the unfolding operators for periodic homogenization, we give a general compactness result for a class of functions defined on bounded domains presenting perforations of two different size. Then we apply this result to the homogenization of the flow of a Bingham fluid in a porous medium with solid obstacles of different size. Next we give the interpretation of the limit problem in term of a non linear Darcy law.

**Comments:**19 pages, 2 figures

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**Affiliations:**

^{1}LEMTA,

^{2}LEMTA,

^{3}LEMTA,

^{4}LEMTA

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