  Turbulent channel flow of drag-reducing polymer solutions is simulated in
minimal flow geometries. Even in the Newtonian limit, we find intervals of
"hibernating" turbulence that display many features of the universal maximum
drag reduction (MDR) asymptote observed in polymer solutions: weak streamwise
vortices, nearly nonexistent streamwise variations and a mean velocity gradient
that quantitatively matches experiments. As viscoelasticity increases, the
frequency of these intervals also increases, while the intervals themselves are
unchanged, leading to flows that increasingly resemble MDR.
