• Proceedings of the Korean Environmental Sciences Society Conference
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• 1999.04a
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• pp.133-136
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• 1999

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1999.10a
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• pp.97-98
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• 1999

• Journal of Ocean Engineering and Technology
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• v.20 no.5 s.72
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• pp.23-29
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• 2006

A quasi depth-varying mathematical model for wind-generated circulation in coastal areas, expressed in terms of the depth-averaged horizontal velocity components and free surface elevation was validated and used to understand the diurnal circulation process. The wind velocity is considered as a dominant factor for driving the current. In this paper, three-dimensional numerical experiments that included the land topography were used to investigate the mesoscale air flaw over the coastal regions. The surface temperature of the inland area was determined through a surface heat budget consideration with the inclusion of a layer of vegetation.A series of numerical experiments were then carried out to investigate the diurnal response of the air flaw and wind-generated circulation to various types of surface inhomogeneities.

• Proceedings of KOSOMES biannual meeting
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• 2006.05a
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• pp.93-102
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• 2006

효율적인 방제전략 수립 지원시스템 개발의 일환으로 환경민감정보 기반 실시간 유출유 확산예측 시스템과 피해위험도 예측시스템을 연계한 해양오염 방제지원시스템을 개발하였다. 실시간 유출유 확산예측시스템에서는 실시간 바람과 실시간 해수유동을 기반으로 유출유의 이동을 계산하고, 유출유 특성에 따라 해상 유출유의 풍화작용을 모델링하여 유출유의 잔류량 및 확산분포를 계산한다. 유출유 확산 예측의 실시간 바람은 국립환경연구원의 실시간 기상모델 결과를 FTP를 이용하여 실시간으로 연계하여 활용하며, 실시간 해수유동으로서 조류는 수치모델결과와 검조소 관측결과의 결합을 통해 실시간 조석을 예측하는 CHARRY (Current by Harmonic Response to the Reference Yardstick) 모델을 이용하여 예측하고, 실시간 취송류는 바람과 취송류간의 상관관계와 반응함수를 이용하여 예측한다. 실시간 해수유동을 따라 이동하면서 풍화되는 유출유의 풍화작용은 유출유 특성에 따라 결정된 감소율을 적용하여 모델링한다. 본 시스템은 이와 같은 정보를 ESI(Environmental Sensitivity Index) 및 방제자원 정보와 통합하여 종합적으로 제공함으로써 방제전략 수립을 지원한다.

• Journal of Ocean Engineering and Technology
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• v.18 no.5
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• pp.22-28
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• 2004

This study constructed a 3D real-time numerical model that predicts the water quality and movement characteristics of the inner bay, considering the characteristics of the wind-driven current and density current in estuaries, generated by the river discharge from the Hyeong-san river and oceanic water of the Eastern sea. The numerical model successfully calculated the seawater circulation current of Yeong-il Bay, using the input conditions oj the real-time tidal current, river discharge, and weather conditions during March 2001. This study also observed the wind-driven current and density current in estuaries that are effected by the seawater circulation pattern of the inner bay. We investigated and analyzed each impact factor, and its relationship to the water quality of Yeong-il bay.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.4
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• pp.295-307
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• 2012

In order to understand the flow properties of the South Sea of Korea, tidal currents, wind-driven currents, density-driven currents and residual flows were investigated by using 3-dimensional numerical model(POM). In offshore regions, tide-induced residual current tends to flow eastward during the spring tide and westward during the neap tide. Total residual flow is irregular due to the bottom topography in the coastal area. The density-driven currents in the coastal area showed to be relatively weak, with little seasonal differences. The special tendency was apparent in the open sea. That is, the flow in the offshore regions showed results similar to that of the Tsushima current. The wind-driven currents in the coastal area showed to be much stronger than in offshore regions. Vertically, the flow of the surface layer was much stronger than that of the bottom layer. Through these results, material transport and diffusion in the south coast, as a basis for predicting the spread of use is expected to be available.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.8 no.1
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• pp.28-36
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• 1996

The influence of vertical eddy viscosity to the nonlinear interaction of tidal current and wind-induced current is examined using a point model. A zero-equation turbulence model is derived by simplifying the q$^2$-q$^2$1 turbulence model under the assumption that the generation of turbulence kinetic energy is balanced with its dissipation and is further modified to include the depth of frictional influence properly The zero-equation turbulence model is derived and the possibility of resonance in the presence of Coriolis effect is suggested. The amplitudes of tidal currents remain the same regardless of the applied wind stress, but the over-tide component is generated due to the nonlinear interaction of tidal current and wind-induced current. Significant changes in the vertical profile of wind-induced currents can occur according to tide-induced background turbulence. The turbulence model can give rise to misleading results when applied to the wind-driven circulation in the tide-dominated sea such as Yellow Sea unless the tide-induced background turbulence is adequately included in the parameterization of vertical eddy viscosity.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.6 no.3
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• pp.245-259
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• 1994

This paper is concerned with the development of a three-dimensional numerical model for coastal circulation and heat transport with improved prediction ability. The model uses fully nonlinear, time-dependent three-dimensional, $\sigma$-transformed equations of motion and equation of heat transport The model was verified with experimental data for wind-driven current in a one-dimensional channel and thermal jets flowing into stagnant waters and applied for unsteady flow induced by tide and thermal jets in coastal waters around Kori nuclear power plant. The model results were in good agreements with experimental data sets for wind-driven current and thermal jet, and field observed data sets in coastal waters. This study has shown that the $\kappa$-$\varepsilon$ turbulence model is applicable to various coastal conditions without any modification of turbulence constants.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.10 no.1
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• pp.27-36
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• 1998

A three-dimensional numerical model of water circulation has been developed. The model employs the equations on $\sigma$-coordinate and the finite element method for numerical integration. To verify accuracy of the model, a series of numerical experiments have been conducted. The experiments include wind-driven currents in an one-dimensional channel, wind-driven currents in a square lake, and tidal current distributions in Masan-Jinhae Bay. The simulation results showed good agreements with the analytic solutions for wind-driven current and the field data sets in Masan-Jinhae Bay. The model can be used widely for modeling of water circulation in the waters with a complex geometry.

• Journal of the Korean earth science society
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• v.18 no.6
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• pp.529-539
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• 1997

The circulations and movement of suspended materials by tidal residual current and seasonal surface wind in the Yellow Sea and the East China Sea are investigated by using a 2-dimensional barotropic model and a particle tracing technique. The tidal residual current is relatively strong around the south and west coast of Korea including the Cheju Island and southern coast of China. The current has a maximum speed of 10 cm/s in the vicinity of Cheju Island with a clockwise circulation. General tendency of the current, however, is to flow eastward along the southern coast of Korea. At the east coast of China from Shanghai to Tunghai, it also shows a eastward flow toward the South Sea of Korea. The anticyclonic circulation formed by wind-driven current and southward current prevails along the coast of Korea in the winter season(from October to April) when northerly wind is dominant. In summer(represented by July), however, the cyclonic circulation appears due to the influence of southerly wind. Suspended materials are advected by tidal residual current and wind-driven current. The long period(ten days) displacement by wind-driven current is bigger than that by tidal residual current. However, the tidal residual current would have the more important role for the advection of the suspended material considering longer period more than several months.