• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.265-265
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• 2017

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.3
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• pp.172-180
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• 2013

The focus of this study is to provide a method for determining the dimension of a submerged breakwater satisfying the target transmission performance or predicting the transmission coefficient of a given structure. This method was developed based on data analysis of the physical experiment that was carried out by using the submerged breakwater composed of double-layer permeable blocks. Two different armor blocks of Tetrapod and Triangular Pyramid Block were used in the experiment. The parameter $K_Th_b/h$ was introduced in the analysis of the measurement data. By using the linear regression line deduced from the analysis of the experimental data, it was possible to readily predict the wave transmission coefficient irrespective different water depths at the crest of the submerged breakwater, under the condition of significant decrease in transmitted wave height due to the submerged breakwater. This method can be effectively utilized for estimating the necessary number of blocks used for the submerged breakwater as well as comparing the transmission characteristics of the submerged breakwater according to use of different armor blocks.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.170-172
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• 2002

해양의 수산자원개발을 위한 새로운 기술의 하나로 용승어장효과를 인공적으로 재현하여 어업생산성을 도모하기 위해 설치되는 인공용승구조물의 수리학적 특성을 검토하고 용승유량에 관한 기본적인 특성에 대해 연구하였다. 대상 인공용승구조물의 구조형식은 블록을 이용한 잠제 형식이며, 블록의 모양은 정육면체이다. 본 연구를 통해서 용승구조물의 용승유량 특성을 검토하고자 한다. (중략)

• Journal of Ocean Engineering and Technology
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• v.21 no.6
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• pp.47-52
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• 2007

This paper presents the design of a submerged breakwater, which functions as an eco-structure in a marine environment. Newly patented blocks were used in the submerged breakwater to both make it stable and provide an inhabitable space for fish. To investigate the wave transmission of the proposed submerged breakwater, parametric studies were conducted through two-dimensional hydraulic tests, which were carried out at the National Fisheries Research and Development Institute (NFRDI) in South Korea. Those parameters are relative crest width (B/L), wave steepness (H/L), relative crest depth (hB/H), and submerged breakwater configuration. The hydraulic experimental results can be used to predict the performance of the proposed submerged breakwater covered with the multi-function blocks.

• Journal of Wetlands Research
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• v.16 no.3
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• pp.327-336
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• 2014

Submerged thin walls are extreme case of submerged rectangular blocks, and could be used for many purposes in rivers or coastal zones, e.g. to tsunami. To understand flow characteristics including flow and pressure fields around a specific submerged thin wall a numerical model was applied which includes computation of hydrodynamic pressure on ${\sigma}$-coordinate. ${\sigma}$-coordinate has strong merits for simulation of subcritical flow over mild-sloped beds. On the other hand ${\sigma}$-coordinate is quite poor to treat sharp structures on the bed. There have been a few trials to incorporate dynamic pressure in ${\sigma}$-coordinate by some researchers. One of the previous approaches includes process of sloving the Poisson equation. However, the above method includes many high-order terms, and requires long cpu for simulation. Another method SOLA was developed by Hirt et al. for computation of dynamic pressure, but it was valid for straight grid system only. Previous SOLA was modified for ${\sigma}$-coordinate for the present purpose and was adopted in a model system, CST3D. Computed flow field shows reasonable behaviour including vorticity is much stronger than the upstream and downstream of the structure. The model was verified to laboratory experiments at a 2DV flume. Time-average flow vectors were measured by using one-dimensional electro-magnetic velocimeter. Computed flow field agrees well with the measured flow field within 10 % error from the speed point of view at 5 profiles. It is thought that the modified SOLA scheme is useful for ${\sigma}$-coordinate system.