The objective of the present study is to investigate the physical processes which take place in the surf zone on a coast with and without coastal structures.
The study shall lead to a significantly improved description of the cross-shore and longshore sediment transport, which mainly occurs within the surf zone.
The study will comprise two tasks: I. Surf and swash zone hydrodynamics and sediment transport, and II. Morphological modelling.
I. The surf and swash zone hydrodynamics and sediment transport is the process-oriented part of the study, and will concentrate on the behaviour of breaking and broken waves (mainly 2D-horizontally), their generation of small and large scale turbulence, and the resulting sediment transport. Breaking and broken waves in the surf and swash zone: This topic will deal with waves just before they break, the processes of wave breaking, the further propagation as a broken wave to the limits of run-up in the swash zone. The role of wave reflection will be included. The study will deal with plane beaches and beaches with bars, where a pause in the breaking will occur. The sediment transport in the surf zone - especially that due to long waves - will be studied.
Vertical and horizontal structure of wave-induced motion: This topic will deal with the structure of vortices and turbulence formed by breaking waves. Special attention will be given to the wave-boundary layer in the surf zone, the 3D-undertow, the behaviour of vortices formed by wave breaking, shear waves formed in the longshore current, and the behaviour of rip currents.
II. Morphological modelling is the integration-oriented part of the study. This task will apply the improved understanding of the fundamental physical processes to improve the morphodynamic description of the surf and swash zone. The morphological modelling will concentrate on the behaviour of the seabed in the surf and swash zone in a real environment, i.e. 3-D irregular waves plus a current. Also the morphology is assumed to be 3-D. The study includes holes in the bars, longshore rhythmic beach features like oblique ridges and beach cusps and the morphological far field impact of coastal structures.
Funding SchemeCSC - Cost-sharing contracts
OX10 8BA Wallingford
2600 MH Delft
2628 BL Delft
BS8 1TW Bristol, Clifton
EH9 3JZ Edinburgh
PL1 2DE Plymouth