Variability of Bed Drag on Cohesive Beds under Wave Action
AbstractDrag force at the bed acting on water flow is a major control on water circulation and sediment transport. Bed drag has been thoroughly studied in sandy waters, but less so in muddy coastal waters. The variation of bed drag on a muddy shelf is investigated here using field observations of currents, waves, and sediment concentration collected during moderate wind and wave events. To estimate bottom shear stress and the bed drag coefficient, an indirect empirical method of logarithmic fitting to current velocity profiles (log-law), a bottom boundary layer model for combined wave-current flow, and a direct method that uses turbulent fluctuations of velocity are used. The overestimation by the log-law is significantly reduced by taking turbulence suppression due to sediment-induced stratification into account. The best agreement between the model and the direct estimates is obtained by using a hydraulic roughness of 10
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Safak, I. Variability of Bed Drag on Cohesive Beds under Wave Action. Water 2016, 8, 131.
Safak I. Variability of Bed Drag on Cohesive Beds under Wave Action. Water. 2016; 8(4):131.Chicago/Turabian Style
Safak, Ilgar. 2016. "Variability of Bed Drag on Cohesive Beds under Wave Action." Water 8, no. 4: 131.
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