Developed Turbulence: On the Energy Cascade

Abstract

It is the energy cascade that explains the origin of Kolmogorov’s similarity hypothesis. The recent direct numerical simulations have revealed that the energy cascade in developed turbulence is caused by the creation of smaller-scale coherent vortices in straining regions around larger-scale coherent vortices. This concrete picture of the energy cascade in terms of coherent structures, however, denies the local equilibrium hypothesis, which is the basis of the Kolmogorov theory.