Experimental Study of Duct Cross-Sectional Area Reduction on Oscillating Water Column Performance Using Wave Period Variations

The development of renewable energy is a key approach to reducing fossil fuel dependence. This study examines the effect of modifying duct geometry into a convergent nozzle shape in an Oscillating Water Column (OWC) system. Experiments were conducted in a laboratory wave flume using sensors to measure wave height and pressure across nine wave period variations. Results show that reducing the cross-sectional area increases pressure by 57% and velocity by 44%, consistent with Bernoulli’s principle. The maximum potential power in the laboratory-scale model was obtained at a wave height of 0.175 m and a wave period of 2.69 s. Using Froude scaling, this corresponds to a prototype wave height of approximately 1.75 m, generating 51.75 W.