Improving predictions of nearshore wave dynamics and coastal impacts using Smooth Particle Hydrodynamic models

In this study we assess the capabilities of the mesh-free, Lagrangian particle method (Smooth Particle Hydrodynamics, SPH) method to simulate the detailed hydrodynamic processes generated by both spilling and plunging breaking waves within the surf zone, and present how the approach can be used to predict a broad spectrum of hydrodynamic processes relevant to coastal applications where wave breaking is important. The weakly-compressible SPH code DualSPHysics was applied to simulate wave breaking over two bathymetric profiles (a plane beach and fringing reef) and compared to experimental flume measurements of waves, currents, and mean water levels. We demonstrate how the model can accurately reproduce a broad range of relevant hydrodynamic processes, ranging from the nonlinear evolution of wave shapes across the surfzone, wave setup distributions, mean current profiles and wave runup. We compare the surfzone predictions with results from other classes of wave models, and illustrate some of the advantages of the SPH approach (particularly in resolving the hydrodynamics above the wave trough). Overall, the results reveal how the mesh-free SPH approach can accurately reproduce the detailed wave breaking processes with comparable skill to state-of-the-art mesh-based Computational Fluid Dynamic models, and how it can be used as a valuable tool to develop new physical insight into surf zone processes.