The present study examines a new concept of wave energy conversion inspired by geological tidal-bowls (i.e. toilet bowls) and blowholes in nature, capitalizing on the Helmholtz resonance phenomenon. Tidal-bowls are of interest because they concentrate ocean wave energy in a basin while in resonance with incoming waves. Tidal-bowls are formed as sea channels grow landwards into a water basin, which can result in a high pulsating current of water inside the channel in and out of the basin. The resonance of water inside the basin produced by asymmetry of its narrow water channel allows for the capture of Helmholtz mode, which is the most energetic mode of the ocean waves. Thus, the objective of this project is to experimentally investigate the geometry of tidal-bowls in a wave tank including the size of the basin and the channel in order to obtain Helmholtz resonance. The model in the wave tank is scaled using the Froude number. Preliminary experiments were carried out measuring the water surface, demonstrating a strong correlation of the model to the theoretical Helmholtz mode’s model, σH2 = gHB/A0L. Where a basin with maximum water depth, H, and horizontal area, A0, is connected to the sea by a narrow strait of width, B, and the strait length, L. The proposed geometry can be used to harvest wave energy through either pulsating current of the channel using a water-turbine or using an air-turbine on the top of the basin. This study aims to catalyze future works in effective applications of this model towards wave energy conversion device development. Thus, we investigated the effects of the device’s length, and the device’s winglet’s angle at the inlet of the channel on wave amplification inside the basin. In addition, we experimentally demonstrated that the flow dampening inside the channel has no effect on basin’s resonance frequency.

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