Temporal dynamics of the alignment of the turbulent stress and strain rate

Abstract

Energy transfer between scales in the turbulent cascade requires geometric alignment between scale-dependent turbulent stresses and strain rates. However, each of these tensors evolves dynamically and differently, leading to nontrivial temporal behavior of this alignment. A numerical simulation of turbulence is used to study this process and, by formulating the energy flux in a fully Lagrangian way, the important role played by deformation in the energy cascade is highlighted.