Harmonic-induced wave breaking due to abrupt depth transitions: An experimental and numerical study

Abrupt depth transitions (ADTs) have been shown to induce the release of bound waves into free waves, which results in spatially inhomogeneous wave fields atop ADTs. Herein, we examine role free-wave generation and spatial distribution higher-harmonic components onset breaking for very steep periodic upon interaction with an ADT. We utilise a Smoothed Particle Hydrodynamics (SPH) model, making use its ability automatically capture overturning surfaces. validate model against experiments. The SPH is found accurately reproduce phase-resolved harmonic up sixth harmonic, particularly vicinity For cases studied, conclude that second-order released at ADT, their linear (beating), drive higher-order bound-wave components, show variation amplitude as result. amplitudes smaller than threshold, this beating phenomenon can be used predict locations where peak values surface elevation are located, whilst also predicting location threshold. Beyond contributions higher harmonics (second-harmonic 60% sixth-harmonic 10% incident amplitude) cause occur nearer hence confined region between ADT first anti-node components. Counter-intuitively, find that, point breaking, steeper display reduced non-linearity result