Experimental and numerical investigation of nonbreaking focused waves using newwave and transient wave packet models

Abstract

This study presents an experimental and numerical investigation of uni-directional non-breaking focused waves generated using the NewWave model and transient wave packets. Model tests in the Deep Ocean Engineering Basin examine the spatial evolution and nonlinear characteristics of focused waves, applying amplitude and phase corrections from linear theory to improve target focusing. The experiments reveal nonlinear energy transfer near the focal point due to wave-wave interactions, leading to crest elevation increases, and quantify viscous energy dissipation during downstream propagation. Numerical simulations are performed in a Higher-Order Spectral (HOS) method-based numerical wave tank(NWT) with cosine bases and influx source generation to treat non-periodic boundaries. The simulations capture third- and higher-order nonlinear interactions, reproducing measured wave elevations and frequency spectra. The results clarify the dependence of wave propagation on the energy band and demonstrate the capability of HOS-based NWT as reliable tools for focused-wave design and analysis in offshore engineering.