Variation of Irregular Waves Passing Over an Artificial Coral Reef (ACR)

Abstract

Hong, S.; Dodaran, A.A.; Kim, T.; Kim, J.; Huynh, V.M.; Lee, J., and Kwon, S., 2021. Variation of irregular waves passing over an Artificial Coral Reef (ACR). In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 524–528. Coconut Creek (Florida), ISSN 0749-0208. To investigate the variation of irregular waves due to an Artificial Coral Reef (ACR), two-dimensional experiments on the wave steepness, wave period, and relative submergence were conducted. The results for the wave transmission coefficient under ACR installation indicated that the wave steepness and period conditions are closely related to wave attenuation, which has similar trends for general coastal structures, even under irregular wave conditions. Additionally, the total spectral energy decreased gradually, whereas an inconsistent peak-energy decrement occurred with a wave steepness of 0.032, which was expected because of spectral energy redistribution due to ACR. The correlation between the relative submergence and spectral energy was investigated via a spectral analysis. In high frequency domain (1.25∼2.25f/f_p), the composition ratio of spectral energy increased with larger relative submergence, whereas opposite trend was observed in low frequency domain (0.25∼0.75f/f_p). The main findings of this study can provide basic knowledge for understanding irregular wave variation over the ACR.