Schematizing wave boundary conditions in sediment transport modeling around a harbour: A case study for Salaverry-harbour, Peru

Schematizing wave boundary conditions in sediment transport modeling around a harbour: A case study for Salaverry-harbour, Peru

Hopmans, R.

Stive, M.J.F. (mentor)
Van Ledden, M. (mentor)
Luijendijk, A.P. (mentor)
De Boer, G.J. (mentor)

Civil Engineering and Geosciences

Hydraulic Engineering

Coastal Engineering

2013-04-25

For many applications in the field of coastal engineering 2D-morphological models are being applied. Due to the large computational effort these models demand it is nearly impossible to include a full wave climate in long-term morphological modeling. This has asked for waveclimate reduction methods in order to reduce the input and consequently the computational time of a simulation. Various methods exist to reduce a wave-climate, from straightforward approaches to more sophisticated ones. In this thesis four methods have been chosen and their outcomes have been compared to each other. From the different simulations with different sets of boundary conditions have followed different longshore sediment transport (LST) rates along both the undisturbed coast as well as along the groyne. In most practical applications the reduced set of conditions is upscaled making use of so-called upscaling factors. This makes it possible to accurately reproduce the LST-rate along the undisturbed coast with a reduced set of conditions but questions arise whether this reduced set still accurately reproduces the LST-rate along a groyne or breakwater that protrudes the surfzone. Various reduced sets of wave-conditions have therefore been applied in a 2Dh-morphological model for the testcase of the Salaverry-harbour in Peru. The LST-rate along the groyne has been upscaled with the same upscaling factor as was used to regenerate the LST-rate along the coast. Results have shown that in this case the choice of an input reduction technique barely influences the accuracy as long as a minimum of 8 conditions is taken into account. Moreover all the reduced sets of conditions based on different input reduction methods reproduce the original LST-rate with an accuracy in the order of 2 to 3 %. In case less than 8 conditions are taken into account the accuracy reduces. Besides that it has been shown that it is more important to account for a variation in both wave height and wave direction rather than solely varying the reduced wave-climate based on one of these characteristics. The value for the grain size diameter influences these outcomes only marginally.

morphological modeling
sediment transport
numerical modeling
boundary conditions

http://resolver.tudelft.nl/uuid:c63416fa-fe52-47d6-980d-f3c4dba3ed88

Student theses

master thesis

(c) 2013 Hopmans, R.