Thermalization and scalings in turbulence

It was argued that application of hyperviscosity in turbulence simulation will lead to artifacts caused by partial thermalization --- the tendency to the physical behavior corresponding to the equilibrium of the Galerkin-truncated inviscid system [U. Frisch et al., Phys. Rev. Letts. in press; or, Arxiv:0803.4269]. We study the partial thermalization physics in three dimensional high-resolution numerical hyperviscous turbulence. Special attention is given to the effect of thermalization on intermittency growth, and, the inertial- and dissipation-range scalings. Hierarchical flow visualizations [J. Clyne et al., New Journal of Physics 9 (2007) 301] are made, discovering coherent structures embedded in the thermalized fluctuations. We will address relevant issues in modeling and simulation of geophysical and atmospheric flows.