Modeling of shallow water waves with variable bathymetry in an irregular domain by using hybrid finite element method

Abstract

An efficient numerical model is constructed with the combination of analytical and Hybrid Finite Element Method (HFEM) based on mild slope equation for shallow water waves to analyze the wave induced oscillation in an irregular geometrical domain. The domain of interest is divided in two regions as bounded and unbounded region. The solution of the mild slope equation is obtained in the bounded region with the consideration of variable bathymetry and partially reflected boundary using Hybrid element method. Further, an analytical approach is utilized in an unbounded region based on Fourier bessel series solution of scattered waves. Hybrid mesh elements is considered for bounded region to enhance the numerical accuracy. The numerical validation is conducted by the comparison of simulation results with analytical approximations and convergence analysis for the rectangular domain is also obtained. The amplification factor is obtained for T-shaped and TT-shaped domain to analyze the resonance modes. Finally, the current numerical model is applied on a realistic Pohang New Harbor (PNH) under the resonance conditions. Thus, the current numerical model can be utilized efficiently for redesigning and constructing artificial ports or harbors in the coastal regions with variable bathymetries.