Numerical and Geometrical Analysis of the Onshore Oscillating Water Column Wave Energy with a Ramp

Abstract:

This study is about a two-dimensional numerical analysis of the influence of a ramp in front on an oscillating water column wave energy converter (OWC-WEC). The main purpose was to evaluate, numerically and geometrically, the effect of using a ramp variation in relation to the frontal wall on the hydropneumatic power of the OWC-WEC. The constructal design method was applied for geometric analysis. The problem had a geometric constraint: the area of the ramp (A₂) and two degrees of freedom: H₂ / L₂ (ratio of the height and length of the ramp) and L₄ (the distance of the ramp concerning the OWC-WEC front wall). In numerical simulations, the equations of conservation of mass, momentum, and an equation for the transport of volumetric fraction were solved using the finite volume method (FVM). The multiphase model volume of fluid (VOF) was applied for the air-water interaction. Thus, the increase in the H₂/L₂ ratio resulted in a decrease of the root mean square (RMS) of the available hydropneumatic power (P_hyd). By varying the distance L₄, the better case was = 6 m and / = 0.025 and the worst case was = 1 m and / = 0.2. The relative difference between the better RMS P_hyd = 150.7957 W and the worst P_hyd = 73.1164 W reached up to a hundred and six percent.

• Periodical: Defect and Diffusion Forum (Volume 412)
• Pages: 11-26
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.412.11
• Online since: November 2021
• Authors: Marla Rodrigues Oliveira, Elizaldo Domingues dos Santos, Liércio André Isoldi, Luiz Alberto Oliveira Rocha, Mateus das Neves Gomes*
• Keywords: Constructal Design, Oscillating Water Column, Ramp, Volume of Fluid

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