On the universality of inertial energy in the log layer of turbulent boundary layer and pipe flows

Abstract

Recent experiments in high Reynolds number pipe flow have shown the apparent obfuscation of the kx-1 behaviour in spectra of streamwise velocity fluctuations (Rosenberg et al. in J Fluid Mech 731:46–63, 2013). These data are further analysed here from the perspective of the $$\log r$$logr behaviour in second-order structure functions, which have been suggested as a more robust diagnostic to assess scaling behaviour. A detailed comparison between pipe flows and boundary layers at friction Reynolds numbers of $${{Re}}_\tau \approx$$Reτ≈ 5000–20,000 reveals subtle differences. In particular, the $$\log r$$logr slope of the pipe flow structure func..