Small-scale anisotropy in stably stratified turbulence

In this paper, small-scale statistics in stably stratified turbulence is studied theoretically and numerically. Expressions for the spectra of the velocity correlation, density fluctuation and buoyancy flux are derived using a perturbation method that generalizes the idea used by Ishihara et al for studying small-scale anisotropy in turbulent shear flows (2002 Phys. Rev. Lett. 88 154501). The expressions give not only the scaling in the inertial subrange but also estimates for anisotropy of the spectra at small scales. They were found to be in good agreement with a direct numerical simulation with 512(3) grid points.