A prediction medod and efficiency of primary conversion of OWC type WEC with projecting walls

This paper describes a method of performance improvement of the efficiency of primary conversion of wave power of an oscillating water column (OWC) type wave energy convertor (WEC) and effects of the projecting walls are investigated with the prediction method presented. Model tests are carried out at a wave tank and a theoretical prediction method is formulated. Projecting walls (PW) are installed on a WEC of OWC types proposed toward wave coming direction. The model test is carried out in regular wave in head sea and oblique waves. The efficiency of primary conversion of the WEC is greater than that of conventional OWC types from the calculations with the present method. The present prediction method is based on the linear potential theory. Conditions of free surface within an air-chamber above the OWC and air pressure in the air-chamber are directly taken into consideration as boundary conditions for the source distribution method. Validity of the prediction method is proven by comparing with results of the model test.