Kim, S.W., and Lee, S.D., 2021. Unsteady flow characteristics at gate of overtopping-type submerged breakwater. 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. 101–105. Coconut Creek (Florida), ISSN 0749-0208.
In this study, through physical model test and numerical modeling for the unsteady flow of the OSB structure, the discharge/velocity characteristics at the openings were reviewed. During the regular waves propagation with a wave height of 2.0 m and a period of 8.0 s, the flow velocity at the opening (x= 0.25 m) was estimated using the water level information on the front and rear of the opening and the empirical equation for the flow rate of the rectangular weir. The discharge velocity estimated from the empirical equation is slightly underestimated, but the overall variations of flow velocity are well reproduced. From these results, it was confirmed that the return of fluid from the opening to the offshore, which contributes to the improvement of OSB performance, occurs due to the difference in water level front and rear of the opening. There is no direct influence of the wave. These facts are planned to be utilized in the study of structure optimization to use the OSB structure as a wave energy converter while at the same time playing the role of submerged breakwater.