Turbulent shear flows on a sparse grid

Abstract

The picture of a turbulent cascade suggests a reduction of the full Navier-Stokes dynamics to interactions on a limited number of shells or modes in wave number space. Instead of modelling small scales by means of an eddy diffusivity, dynamics at all scales can be represented on a sparse spectral grid, which gets coarser towards large wave numbers, while preserving the structure of nonlinear interactions. In this note we extend previous efforts in homogeneous turbulence to the case of wall bounded flows.