Small-scale Energy Transfer in Turbulence

The dynamics behind the multi-scale energy transfer in turbulent flows is investigated by introducing morphing continuum conservation laws on the basis of the Boltzmann-Curtiss kinetic theory. The resulting conservation laws reveal the existence of small-scale routes for the flow of energy broading the view on energy cascade (forward or inverse). The comparison of the turbulence characteristic with the reference study indicates that the turbulence features in both frameworks are equivalent at the global and small-scales. The analysis reveals that at the small-scale both forward and inverse energy cascade exist in homogeneous isotropic turbulence while an overall negative energy flux (forward cascade) is present globally.