  The interaction between turbulent axisymmetric wakes plays an important role
in many industrial applications, notably in the modelling of wind farms. While
the non-equilibrium high Reynolds number scalings present in the wake of
axisymmetric plates has been shown to modify the averaged streamwise scalings
of individual wakes, little attention has been paid to their consequences in
terms of wake interactions. We propose an experimental setup that tests the
presence of non-equilibrium turbulence using the streamwise variation of
velocity fluctuations between two bluff bodies facing a laminar flow. We have
studied two different sets of plates (one with regular and another with
irregular peripheries) with hot-wire anemometry in a wind tunnel. By acquiring
streamwise profiles for different plate separations and identifying the wake
interaction length for each separation it is possible to show that the
interaction between them is consistent with non-equilibrium scalings. This work
also generalises previous studies concerned with the interaction of plane wakes
to include axisymmetric wakes. We find that a simple mathematical expression
for the wake interaction length based on non-equilibrium turbulence scalings
can be used to collapse the streamwise developments of the second, third and
fourth moments of the streamwise fluctuating velocity.
