Abstrakt: We study slow-fast systems of coupled equations from fluid
dynamics, where the fast component is perturbed by additive noise. The
focus will be on the Navier-Stokes equations, although the techniques
presented generalize to other models as well. We prove that, under a
suitable limit of infinite separation of scales, the slow component of
the system converges in law to a solution of the initial equation
perturbed with transport noise, and subject to the influence of an
additional Itō-Stokes drift. The obtained limit equation is very similar
to turbulent models derived heuristically. Based on joint work with
Arnaud Debussche.