Numerical modelling of wave downfall pressures on the deck landward of a vertical breakwater

Storms and associated violent wave events have increased in frequency and intensity over the last number of years and this trend is set to continue in line with climate change and sea level rise predictions. Structures located directly landward of coastal structures are at risk from violent wave events and corresponding white-water overtopping. Depending on circumstances, experimental investigations into these effects may be expensive and difficult to undertake. This paper investigates the ability of Smoothed Particle Hydrodynamics (SPH), a particle-based simulation method, to model these kinds of violent wave events. With numerical simulations being generally economic and faster to complete, developing a numerical model such as the one proposed in this paper would give designers a powerful tool to help design structures located landward of coastal defences and the defences themselves. The work presented herein is aimed at demonstrating the ability of the SPH method to model violent wave events against vertical seawalls by comparing the results from the numerical model to those obtained experimentally. The pressure envelopes obtained from the numerical and experimental models show general agreement where the mean and median of the uprush velocities from the SPH simulations are within 7% of the experimental data, thus confirming the potential of the SPH approach for this application.