  We study the homogenization of a steady diffusion equation in a highly
heterogeneous medium made of two subregions separated by a periodic barrier
through which the flow is proportional to the jump of the temperature by a
layer conductance of the same order of magnitude of the materials in
consideration. The macroscopic governing equations and the effective
conductivity of the homogenized model are obtained by means of the two scale
convergence technique. We show that under some hypothesis the homogenized
systems contain convective terms of order one.
