Date of Award
Master of Science in Ocean Engineering
Annette R. Grilli
A phase resolving model (FUNWAVE) is used to simulate the 100-year storm. Results are compared to those of the FEMA approved phase averaged model STWAVE, allowing for a direct comparison of water elevations along the coast of Narragansett R.I. Effects of sediment erosion/deposition are taken into consideration using the model XBeach to predict changes to the coastline, which are then used in FUNWAVE’s grid to model wave runup. The test site for this study is Narragansett Town Beach (R.I) and the surrounding infrastructure in the area. Results show a significant amount of beach erosion/deposition along the Town Beach, but not much elsewhere as it is mostly rocky coastline protected by a seawall. Comparisons of significant wave heights predicted by STWAVE and FUNWAVE show a stark difference with much higher values predicted by the phase resolving model FUNWAVE. This increase in wave height results from dynamic wave setup, which is not modeled the phase-averaged model STWAVE. Empirical calculations for wave runup (Stockdon et. al., 2012) compare very well to FUNWAVE’s results, while STWAVE clearly underpredicts runup. Impulse forces calculated along the coastline greatly increase when sediment erosion is considered, with much higher values occurring in the nearshore area of the eroded coastline. Differences in the predicted wave heights between the simulations performed in this study show the importance of using a phase resolving wave model, which is the only way to include the additional effects of dynamic wave runup.
Westcott, Gregory, "PREDICTING 100-YEAR STORM WAVE'S RUNUP FOR THE COAST OF RHODE ISLAND USING A FULLY NONLINEAR MODEL" (2018). Open Access Master's Theses. Paper 1312.