Nonlocal Treatment of the Buoyancy-Shear-Driven Boundary Layer

Abstract

A successful description of a convective boundary layer requires that the model employed takes into account the nonlocal nature of turbulent convection. In this paper new third-order moments (TOMs) are presented and tested. Numerical solutions are obtained using mean flow components and second-order moments as input. The problem of the turbulent damping of the TOMs is considered. The terms in the dynamic equations responsible for the unphysical growth of the TOMs are parameterized, taking into account their dependence on the integral length scale vertical profile. The calculated profiles are presented and tested against large-eddy simulation data and aircraft measurements. In both cases the results compare favorably.