Axisymmetric turbulent wakes with new non-equilibrium similarity scalings*

The recently discovered non-equilibrium turbulence dissipation law (Seoud \& Vassilicos PoF 19, 2007, Mazellier \& Vassilicos PoF 22, 2010, Valente \& Vassilicos JFM 687, 2011, Valente \& Vassilicos PRL 108, 2012, Gomes-Fernandes et al. JFM 711, 2012) implies the existence of axisymmetric turbulent wake regions where the mean flow velocity deficit decays as the inverse of the distance from the wake-generating body and the wake width grows as the square root of that distance. This behaviour is different from any documented boundary-free turbulent shear flow to date. Its existence is confirmed in wind tunnel experiments of wakes generated by plates with irregular fractal-like edges placed normal to an incoming free stream.