Modelling and analysis of fine sediment transport in wave-current bottom boundary layer

Doctoral Thesis (2018)
Author(s)

L. Zuo (TU Delft - Coastal Engineering)

Contributor(s)

D. Roelvink – Promotor (TU Delft - Coastal Engineering)

Y.J. Lu – Promotor

Research Group
Coastal Engineering
Copyright
© 2018 L. Zuo
More Info
expand_more
Publication Year
2018
Language
English
Copyright
© 2018 L. Zuo
Research Group
Coastal Engineering
Bibliographical Note
Dissertation submitted in fulfillment of the requirements of the Board for Doctorates of Delft University of Technology and of the Academic Board of IHE Delft Institute for Water Education.@en
ISBN (print)
978-1-138-33468-7
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

The evolution and utilization of estuarine and coastal regions are greatly restricted by sediment problems. This thesis aims to better understand fine sediment transport under combined action of waves and currents, especially in the wave-current bottom boundary layer (BBL). Field observations, experimental data analysis, theoretical analysis and numerical models are employed. Silt-dominated sediments are sensitive to flow dynamics and the suspended sediment concentration (SSC) increase rapidly under strong flow dynamics. This research unveils several fundamental aspects of silty sediment, i.e., the criterion of the incipient motion, the SSC profiles and their time-averaged parameterization in wave-dominated conditions. An expression for sediment incipient motion is proposed for silt-sand sediment under combined wave and current conditions. A process based intra-wave 1DV model for flow-sediment dynamics near the bed is developed in combined wave-current conditions. The high concentration layer (HCL) was simulated and sensitivity analysis was carried out by the 1DV model on factors that impact the SSC in the HCL.Finally, based on the 1DV model, the formulations of the mean SSC profile of silt-sand sediments in wave conditions were proposed. The developed approaches are expected to be applied in engineering practice and further simulation.