Force reduction on ocean structures with perforated members

Presence of perforated members in ocean structures reduces the wavestructure interaction significantly; breakwaters with perforated members are classicalexamples of such kind. Detailed analyses to quantify the force reduction ocean structures encompassed with perforated covers are scarce in the literature. Present study is focused on the hydrodynamic response of perforated members under regular waves using numerical simulation; results are also validated with the experimental studies. Hydrodynamic responses of cylinders with and without perforated cover are estimated for different sea states. Force reduction, in the presence of perforated outer cover is quantified and validated with the existing experimental results. Based on the studies carried out, it is shown that the maximum reduction is about 14 %. Results of the numerical simulations compare well with that of the existing experimental results with the maximum error of about 6 %.