Abstract
The estimation of the bed shear stress is a crucial step in many sediment transport formulae since, when bedload is dominant, sediment transport can be parameterized in terms of the bed shear stress. In this work, the performance of a new bed shear stress estimator for nonlinear waves is analysed. The effects of velocity and acceleration skewness are incorporated in the time-varying bed shear stress using two parameters: the index of skewness or nonlinearity, r, and the waveform parameter, phi. The results are compared with two different data
sets obtained in the Aberdeen Oscillatory Flow Tunnel, under accelerated-skewed oscillatory flows. When applied to a typical bedload formula, the new expression considerably improves the prediction of the net sand transport rates. A sensitivity analysis for the phase-lead between the bed shear stress and the outer flow indicates that the new expression provides the best trends between predicted and measured transport rates when compared to other parameterizations. This work provides further insights in the correct prediction of sediment transport modelling, accounting for the effect of nonlinear wave shapes.
sets obtained in the Aberdeen Oscillatory Flow Tunnel, under accelerated-skewed oscillatory flows. When applied to a typical bedload formula, the new expression considerably improves the prediction of the net sand transport rates. A sensitivity analysis for the phase-lead between the bed shear stress and the outer flow indicates that the new expression provides the best trends between predicted and measured transport rates when compared to other parameterizations. This work provides further insights in the correct prediction of sediment transport modelling, accounting for the effect of nonlinear wave shapes.
Original language | English |
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Pages (from-to) | 2007-2011 |
Number of pages | 5 |
Journal | Journal of Coastal Research |
Volume | 64 |
Issue number | SI |
Publication status | Published - 2011 |
Event | International Coastal Symposium 2011 - Szczecin, Poland Duration: 9 May 2011 → 14 May 2011 |
Keywords
- bed shear stress
- sand transport
- non-linear waves
- oscillatory flow