Numerical investigation of partially submerged H-type porous barrier in front of a seawall

This study examines the hydrodynamic response of an H-type porous breakwater positioned at a specified distance from a partially reflecting seawall using linear wave theory. The boundary value problem is solved using the dual boundary element method (DBEM) to acquire numerical results for various values of barrier porosity, relative submergence depth, wave steepness, and seawall porosity. The present study shows that for k0h ≥ 1, specifying the porosity to 20 % reduces the reflection coefficient KR by about 21 %, while increasing the wave run-up coefficient KH by nearly 19 %, with the corresponding peak vertical force and moment coefficients increasing by approximately 12 % and 19 %, respectively. Furthermore, during the short-wave period (higher), for wave steepness values increasing from 0.05 to 0.125, the reflection coefficient increases by around 16 % and wave run-up decreases by around 19 %, with negligible vertical force and little influence on the moment coefficient. These findings provide useful guidance for the efficient and economical design of porous breakwater systems.