Contribution of solitons to enhanced rogue wave occurrence in shallow depths: a case study in the southern North Sea

The shallow waters off the coast of Norderney in the southern North Sea are characterised by a higher frequency of rogue wave occurrences than expected. Here, rogue waves refer to waves exceeding twice the significant wave height. The role of nonlinear processes in the generation of rogue waves at this location is currently unclear. Within the...

When Do JONSWAP Spectra Lead to Soliton Gases in Deep Water Conditions?

When a large number of solitons dominates the dynamics of a system, scientists describe this collective behaviour of solitons as a soliton gas. Soliton gases are currently the subject of intense practical and theoretical investigations. The existence of soliton gases has been confirmed in experiments, but is not clear what kind of sea states...

Water-depth identification from free-surface data using the KdV-based nonlinear Fourier transform

We propose a novel method to determine the average water depth from shallow, weakly nonlinear water waves that are approximated by the Korteweg-de Vries equation. Our identification method only requires free-surface measurements from two wave gauges aligned in the direction of wave propagation. The method we propose is based on comparing...

Comparative analysis of bore propagation over long distances using conventional linear and KdV-based nonlinear Fourier transform

In this paper, we study the propagation of bores over a long distance. We employ experimental data as input for numerical simulations using COULWAVE. The experimental flume is extended numerically to an effective relative length of x/h=3000, which allows all far-field solitons to emerge from the undular bore in the simulation data. We apply the...

Analysis of nonlinear ship-induced 3d wave fields using nonlinear fourier transforms

In the past decade, observations in the German estuaries such as the rivers Elbe and Weser show increasingly serious damage to bank protection structures (groins and revetments). This damage is caused mainly by waves induced by the passing of big container ships in the shallow and narrow maritime waterways. These ship-induced 3D wave fields...

Analysis of nonlinear ship-induced 3d wave fields using nonlinear fourier transforms

In the past decade, observations in the German estuaries such as the rivers Elbe and Weser show increasingly serious damage to bank protection structures (groins and revetments). This damage is caused mainly by waves induced by the passing of big container ships in the shallow and narrow maritime waterways. These ship-induced 3D wave fields...

Analysis of Bore Characteristics Using KdV-Based Nonlinear Fourier Transform

Bores propagating in shallow water transform into undular bores and, finally, into trains of solitons. The observed number and height of these undulations, and later discrete solitons, is strongly dependent on the propagation length of the bore. Empirical results show that the final height of the leading soliton in the far-field is twice the...

Nonlinear Fourier Analysis of Free-Surface Buoy Data Using the Software Library FNFT

Nonlinear Fourier Analysis (NFA) is a powerful tool for the analysis of hydrodynamic processes. The unique capabilities of NFA include, but are not limited to, the detection of hidden solitons and the detection of modulation instability, which are essential for the understanding of nonlinear phenomena such as rogue waves. However, even though...

Wellenbelastung und Stabilitat hydraulisch gebundener Deckwerke

Many sea dikes along the coast of the North Sea are protected against wave loading and currents by riprap revetments that are grouted with mortar. The mortar bonds the individual stones of the top layer, thereby forming a coherent structure that is able to withstand normal forces and shear forces as well as momentums, thus leading to a planar...