Author(s): Sundar. V; Sannasiraj. S. A; John Ashlin. S; Jegatheeswaran. B
Linked Author(s): Vallam Sundar, Sannasi Annamalaisamy Sannasiraj
Keywords: Regular waves; Hydrodynamic efficiency; Energy absorption factor; Wave amplification; Pressure ratios
Abstract: The effect of the shape inside the chamber of an oscillating water column (OWC), integrated with bottom fixed breakwater on its efficiency is considered. For this study, an oscillating column device with four different bottom profiles (flat bottom, bottom with a slope of 1: 1 and1: 1. 5 and circular arc bottom of radius 300mm) are considered. The models were installed in a water depth of 0. 5m and subjected to waves with period varying from 1s to 2. 4s thus covering a steepness ranging between 0. 01 and 0. 06 and relative water depth, d/L from 0. 09 to 0. 33. For each of the four models as stated above, exposed to regular waves, the variations of hydrodynamic efficiency, energy absorption factor, amplification factor, and pressure ratios are studied and the results are plotted as a function of relative water depth. From the hydrodynamic efficiency, the natural period of an individual chamber is found as 1. 9s and the circular arc bottom profile is found to have maximum hydrodynamic efficiency compared to the other bottom profiles considered.