Karsten Lindegård Jensen, B. Mutlu Sumer, Giovanna Vittori, Paolo Blondeaux


The pressure field in an oscillatory boundary layer is obtained by means of direct numerical simulations (DNS). The vertical pressure gradient is treated as any other turbulence quantity and its statistical properties are calculated from the DNS data. Moreover, a criterion involving the vertical pressure gradient is used to detect spots. The large fluctuations of the vertical pressure gradient, which take place in the turbulent flow, have significant implications for sediment transport.


wave boundary layers; turbulence; vertical pressure gradient; DNS; transition to turbulence

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