STUDYING THE EFFECT OF LINEAR REFRACTION ON LOW-FREQUENCY WAVE PROPAGATION (PHYSICAL AND NUMERICAL STUDY)

Sepehr Eslami Arab, Ap van Dongeren, Peter Wellens

Abstract


This paper describes a laboratorium data set of wave propagation over steep slopes with large angles of incidence, and the model-data comparison with linear and nonlinear wave models (SWAN and TRITON). The reason for this study is that the SWAN model showed an underestimation of the observed low frequency wave energy at nearshore sites in the Eastern Wadden Sea tidal inlet. Van Vledder (2010) showed that potential inaccuracies in modeling refraction over steep slopes of the tidal channel may result in observed discrepancies. The paper addresses the set up of the laboratory experiment, the novel measurement techniques and an analysis of the observed differences between models and data. The results show that there is not one single mechanism that explains the differences, but a combination of mechanisms, and perhaps other phenomena such as reflection play role.

Keywords


Refraction; long waves; wave propagation; SWAN; Laboratory measurements; experimental techniques

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