Numerical and experimental study of several passive wave absorber behavior in a wave channel

Wave channels are essential facilities for testing physical models at a laboratory scale, playing a pivotal role in advancing wave energy technology and understanding wave interactions with the coastal infrastructure. These channels enable researchers to simulate real-world conditions and gather critical data, which is instrumental in the development of wave energy converters and coastal defense mechanisms. The quality and reliability of the experimental results are highly dependent on several factors. The precision and capabilities of the wave generator determine the accuracy of the wave conditions replicated. The efficiency of the wave absorber is crucial for minimizing reflections that could skew results. The length of the test section allows for a more comprehensive study of wave behaviors over extended distances. Finally, the accuracy of the measurement instruments used ensures that data collected is precise and reliable. Each of these components is integral to creating a robust experimental setup that can yield meaningful and applicable insights. This work presents the numerical analyses and experimental validation of the interaction of waves with six different geometries of wave energy absorbers with the aim of selecting that one to provide the greatest dissipation based on the wave refractive index. For the numerical simulation, two-dimensional models were studied using the Reynolds-averaged Navier-Stokes (RANS) equations, the k-ω turbulence model and the fluid volume method to address the water-air interaction. The response variable utilized to compare the different geometries of the absorbers was the wave reflection coefficient. The numerical results showed that the lowest wave reflection index was that one obtained with the geometry defined by an arc of length 0.888 m and radius 1.124 m. Finally, a series of experiments were carried out in a wave channel where the height of the waves above the energy absorbers was measured to validate the numerical results.