Spectral Properties of the Universal Velocity Profile for Wall Bounded Flows

This paper presents a novel method for investigating scale separation within wall-bounded turbulent flows based on linear stability theory and the recently formulated Universal Velocity Profile [4]. The method rests on the uniform validity of the Universal Velocity Profile for wall- bounded flows at all Reynolds numbers from the wall to the centerline, and the strict stability of the mean velocity profile across several orders of magnitude in the friction Reynolds number verified using numerical calculations. The results are given in terms of eigenstructures derived from linear stability theory that might be considered precursors of coherent vortical structures in the flow.