Hydrodynamic Performance of an Inverted Trapezoidal Breakwater with Permeable Retrofit

Abstract

The scattering of incident waves by a surface-piercing inverted trapezoidal breakwater (SPTB) encircled by retrofit is numerically examined based on the assumptions of potential flow theory. The dual boundary element method is adopted to evaluate the hydrodynamic performance of the retrofitted SPTB breakwater. The scattering coefficients (i.e., wave transmission, wave reflection, energy loss), and force coefficients acting on the inner SPTB and outer retrofit are reported against relative water depth for various input values of breakwater and incident waves. The SPTB with 10% porosity, spacing S/h=0.25, width varied within 1.5≤B/W≤2, and depth d/h=0.2 is suggested against the incident waves to secure the coastal infrastructure.