Coastal Bottom Boundary Layers And Sediment Transport

This book is intended as a useful handbook for professionals and researchers in the areas of Physical Oceanography, Marine Geology, Coastal Geomorphology and Coastal Engineering and as a text for graduate students in these fields. With its emphasis on boundary layer flow and basic sediment transport modelling, it is meant to help fill the gap between general hydrodynamic texts and descriptive texts on marine and coastal sedimentary processes. The book commences with a review of coastal bottom boundary layer flows including the boundary layer interaction between waves and steady currents. The concept of eddy viscosity for these flows is discussed in depth because of its relation to sediment diffusivity. The quasi-steady processes of sediment transport over flat beds are discussed. Small scale coastal bedforms and the corresponding hydraulic roughness are described. The motion of suspended sand particles is studied in detail with emphasis on the possible suspension maintaining mechanisms in coastal flows. Sediment pickup functions are provided for unsteady flows. A new combined convection-diffusion model is provided for suspended sediment distributions. Different methods of sediment transport model building are presented together with some classical models.

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 phase-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.

This book treats the subject of sediment transport in the marine environment, covering transport of non-cohesive sediment by waves and current in- and outside the surf zone. The primary aim of the book is to describe the physical processes of sediment transport and how to represent them in mathematical models.

This volume contains papers presented in a symposium on Shelf Sediment Transport conducted at the annual meeting of the Geological Society of America held in Washington, D.C., November 1971.

This book expounds the hydraulics of fine sediment which is almost ubiquitously found in coastal and estuarine waters, and in rivers, lakes, and reservoirs. Although the basic subject may be categorized as applied marine physics in shallow waters, several physicochemical and biological effects on particulate transport have been addressed.In this second edition most of the chapters have been substantially updated, rewritten, and expanded. Overall, a significant change has also been made throughout by replacing sediment concentration, a unit dependent quantity at the heart of numerous descriptions, measurements, and calculations, with the nondimensional sediment volume fraction. It marks a divergence in the manner in which fine sediment transport data and calculations are conventionally presented.The book is mainly written for civil engineering seniors and graduate students, to offer a comprehensive foundation in hydraulics of fine sediment. The book is also a useful reference for researchers interested in the effects of physical chemistry and biology on fine sediment transport in water and to an extent on coastal and estuarine morphodynamics, sediment transport, port and harbor engineering, and applied shallow watwer marine physics. The book is also recommended reading for those interested in understanding particle transport in water.Related Link(s)

The benthic boundary layer is the zone of water and sediment immediately adjacent to the bottom of a sea, lake, or river. This zone is of considerable interest to biologists, geochemists, sedimentologists, and engineers because of very strong gradients of energy, dissolved and solid chemical components, suspended matter, and the number of organisms that live there. It is, for example, the sink for anthropogenic substances and the home of microscopic plant life that provides the nutrients that determine fish populations--and ultimately the size of the fisheries. This book of original chapters edited by Professors Boudreau and Jorgensen, both leading researchers in the field, will meet the need for an up-to-date, definitive text/reference on measurements, techniques, and models for transport and biochemical processes in the benthic boundary layer. Each chapter provides a comprehensive review of a selected field, with illustrated examples from the authors' own work. The book will appeal to professionals and researchers in marine biology, marine chemistry, marine engineering, and sedimentology.