Direct numerical simulation of an stably stratified Ekman flow from the Incompact3D Code
Keywords:Direct numerical simulation, Ekman layer, Stable layer
AbstractIn a diurnal cycle, distinct thermal and mechanical forcing generates different manifestations of a planetary boundary layer. The stable boundary layer occurs when the soil surface has a lower temperature than the air above. In this layer, wind shear is the main mechanism of turbulence generation. In the present study, a direct numerical simulation of an Ekman layer over a smooth wall is presented to investigate the different turbulent patterns that occur during evolution from a neutral boundary layer to a weakly stable boundary layer. The preliminary study shows the appearance of turbulent structures near the surface, due to the imposition of a stratification.
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