Wave action on perforated caisson breakwaters

Based on nonlinear wave theory of viscous fluid, the Volume of Fluid (VOF) method is used to determine wave pressure on perforated caisson breakwaters and the arm of wave force on them. Numerical calculations are carried out to examine the relationship among the reflection coefficient, wave pressure and the arm of wave force on perforated caissons. The calculated results show that wave pressure distribution on the inner side and the outer side of front perforated plate and that on the back solid plate of perforated caissons are similar to that on solid structures. Again, wave pressure difference between pressure on the outer side of front perforated plate and that on the back solid plates of perforated caissons is smaller when the reflection coefficient is greater. Moreover, it is found that pressure reductions on the upper porous part of the partially perforated caissons are smaller than those on the lower impermeable part of the partially perforated caissons as the ratio of the arm of wave forces between perforated caissons and solid structures is bigger than 1.0.