The 24th IAHR-APD Congress (24th IAHR-APD Congress)

556 / 2024-07-29 15:56:24

Numerical simulation of storm surges under wave-current interaction: a case study of “Chan-hom”

Storm surge; wave-current interaction; coupled model; typhoon

Subtheme 8: Estuarine and Coastal Engineering > Topic 1: Estuarine Coastal Evolution and Dynamic Mechanisms

Based on the FVCOM hydrodynamic model and the FVCOM-SWAVE wave model, a coupled wave-current storm surge coupled model induced by typhoon Chan-hom was constructed. The paper explores the impact of wave-current interaction on surge elevations, significant wave height, surface and bottom flow velocities. The results show that the distribution of significant wave heights is closely related to the wind speed and structure of the typhoon, with wave energy concentrating on the right side of the typhoon's path and peaking at the time of the maximum wind speed. The wave-current interaction has a greater impact on bottom current velocities than on surface current velocities, primarily occurring in nearshore areas and within the maximum radius of the typhoon. For Typhoon Chan-hom, the wind field is the dominant factor affecting storm surge, with the maximum surge reaching up to 2 m, concentrated in the nearshore areas of Zhejiang and Hangzhou Bay. The pressure effect intensifies in open sea areas, with a surge range within 0.35 m. The nonlinear interaction between astronomical tide and storm surge is enhanced in nearshore areas, with the affected range similarly concentrated in the nearshore areas of Zhejiang, Jiangsu, and Hangzhou Bay, with the maximum surge reaching up to 1.2 m. The impact of wave-current interaction on storm surge in nearshore areas is significant, with an influence range similar to the former, and the maximum surge is about 0.5 m. The research findings provides an important reference for disaster prevention and mitigation in estuarine and coastal areas.