  We explore the behavior of periodic arrays of magnetic nanowires by
micromagnetic simulations using the Nmag modeling package. A large number of
modeling studies on such arrays of nanowires have been performed using finite
size models. We show that these finite size micromagnetic descriptions can only
be used in specific situations. We perform a systematic study of more or less
dense 1D and 2D arrays of nanowires using either finite size or infinite size
models and we show that finite size models fail to capture some of the features
of real infinite systems. We show that that the mean field model scaled to the
system porosity is valid. This work can be used as a basis to the extension of
micromagnetic calculations of the magnetization dynamics in arrays of
nanowires.
