Application of the<i>E</i>– ϵ Turbulence Closure Model to the Neutral and Stable Atmospheric Boundary Layer

Abstract

In the E – ε turbulence model an eddy-exchange coefficient is evaluated from the turbulent kinetic energy E and viscous dissipation ε. In this study we will apply the E – ε model to the stable and neutral atmospheric boundary layer. A discussion is given on the equation for ε, which terms should be included and how we have evaluated the constants. Constant cooling rate results for the stable atmospheric boundary layer are compared with a second-order closure study. For the neutral atmospheric boundary layer a comparison is made with observations, large-eddy simulations and a second-order closure study. It is shown that a small stability effect can change the neutral atmospheric boundary layer quite drastically, and therefore, it will be difficult to observe a neutral boundary layer in the atmosphere.