The structure of the turbulent Ekman layer

Abstract

A mathematical model is employed for analysing the structure of the homogeneous ocean surface layer. The model is verified against laboratory measurements of the fully developed channel flow and the wind-induced channel flow. Turbulence models of different complexities are used and discussed. An extension of the k — ê turbulence model to rotating flows is derived and tested.

The study indicates that a suitably chosen constant eddy viscosity is adequate for predicting the velocity and shear stress distributions in the Ekman layer. For transport of different chemical and biological species it is, however, necessary to know the detailed transport properties of the layer. Non-dimensional vertical distributions of different turbulence quantities, characterizing the Ekman layer, are therefore predicted and analysed. Rotational effects in the turbulence model are found to somewhat change the shear stress distribution in the deeper parts of the boundary layer.