• 한국해안해양공학회지
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• 제18권4호
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• pp.301-307
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• 2006

서해안과 같이 큰 조차를 가진 연안해역에서 항만건설과 매립사업이 널리 진행되고 있으며, 대부분의 사업은 방조제 건설을 필요로 한다. 대부분의 방조제는 내부와 외부사이에 해수가 교환되지 않으나, 사석만을 사용해서 축조된 방파제와 가호안의 투수성 제방에서는 해수가 교환된다. 내부의 수면은 외부 조위의 변화에 따라 시간에 따라 변화하나 그 조차는 해수교환시 제방에서의 큰 마찰로 인하여 외부보다는 작다. 지금까지의 연구에서는 제방을 통한 해수교환을 무시하는 것이 조석모델링에서 일반적이다. 이는 내부의 해수면 변화를 계산할 수 없을 뿐 아니라 물막이 공사와 같이 일부 개방구간이 존재하는 경우에 개방구간만을 통한 해수교환량만을 고려하고, 제체를 통한 해수교환량을 무시하여 내부의 조위와 실제 해수교환량을 부정확하게 계산한다. 본 연구에서는 지하수이론을 이용하여 해수유동모의시 투수성 제체를 통한 해수교환량을 정확히 고려할 수 있도록 하였다.

• 한국해양공학회지
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• 제18권6호
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• pp.22-28
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• 2004

A mathematical model has been developed to evaluate the capability of sea water exchanges under tidal and diffusive environments and has been verified through comparison with numerical experiments. From the mathematical analysis, this study presents the rates of sea water exchanges due to the tidal inflow and diffusion process. The port characteristic length $L_p$ is the most significant evaluation index.

• 한국해양공학회지
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• 제24권3호
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• pp.21-30
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• 2010

This study presents a numerical simulation of sea water-exchange as a preliminary accessing tool of water quality in the protected shore behind a overtopped breakwater. The overtopped breakwater is taken into account for a safe swimming and beach protection. The overtopping rate is calculated by empirical models and the consequent currents, known as wave-induced currents, are calculated under the conditions of H.W.O.S.T and L.W.O.S.T. The rate of sea water exchange is used to evaluate the characteristics of sea water exchange and calculated through the simulation processes such as advective discharging through the outlets and random-walking diffusion of particles released within a basin. The numerical results show that the overtopped waves sufficiently improve the water exchange without healthless stagnation of contaminated mass and the consequent currents are not too strong for swimming.

• 한국해양공학회지
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• 제14권3호
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• pp.11-19
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• 2000

This study aims to examine the characteristics of the water quality variation in relation to the change of water exchange rate with respect to the development phases of the Pusan port. To clarify the characteristics, water exchange caused by the variations of coastline shape and water surface area was examined by the numerical experiments using the Lagrangian particle tracking model based on 2-D shallow water equation. As the results of numerical experiments, it was proved that the water exchange in the Pusan port was decreased mainly due to the port development and the breakwaters construction. During the port development phases from 1875 to 1998, 35% of the sea-space in the port had decreased to make hinterland spaces. This resulted in the loss of wet-land and coastline change as well as decrease of the water exchange rate at the sea side. The city population in that period had rapidly increased from several thousands to 4 millions, resulting in the large discharge of sewages into the port area. Under the these environmental conditions, it can be clearly said that the water quality in the Pusan port is sensitively affected by the discharge of urban sewages decrease of the water exchange rate in relation to port and urban developments. In the study, the temporal changes of water quality were discussed with respect to the port development phases. It was clear that the water quality wad controlled by the exchange rate change under the port development as well as the input impact into the port from the urbanized city area. To make clean sea of the Pusan port, it is suggested that the sewage control, the water exchange and coastline control should be systematically checked under the concept of eco-friendly development and environmental management.

• 한국항해항만학회지
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• 제26권2호
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• pp.227-233
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• 2002

만의 일부만이 개방되어 있고 어선이나 군함 등의 선박통항이 빈번한 당항만을 대상 해역으로 하여 폐쇄성 연안해역의 해수유동에 관해 고찰하였다.

• Journal of the korean society of oceanography
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• 제37권3호
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• pp.169-177
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• 2002

An eddy-resolving free-surface primitive-equation model with nonlinear terrain-following coordinates is established to study the exchange of water masses among the Asian marginal seas and their adjacent waters. A curvilinear coordinate system is used to generate the horizontal grid with a variable resolution for the regional oceans from $5^{\circ}$S to $45^{\circ}$N and $100^{\circ}$E to $155^{\circ}$E. The higher resolution region has about a 10 km by 10 km grid covering the complex geometry of the coastal marginal seas, while the lower resolution region has about a 30 km by 30 km grid covering the eastern Pacific. The model is initialized by the Levitus annual climitology and forced by the monthly mean air-sea fluxes of momentum, heat, and freshwater derived from the Comprehensive Ocean-Atmosphere Data Set. High-resolution and low-viscosity are identified as the key factors for a better representation of the exchange of waters through narrow straits and passages between the marginal seas and their adjacent waters. The dynamics of the loop currents and eddies in the South China Sea and Celebes Sea are examined in detail. It has found that the anticyclonic loop and detached eddies from the Kuroshio through the Luzon Strait play an important role in transporting warm and salty water into the South China Sea, while the cyclonic circulation of the Mindanao Current in the Celebes Sea plays a role in contributing cold water to the Indonesian throughflow. The deep undercurrent of the western Pacific is shown to provide fresher water to the South China Sea and Celebes Sea. These modeling results suggest that the exchange processes via the narrow straits and passages are of fundamental importance to the maintenance of water masses for the marginal sea region.

• 한국수자원학회논문집
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• 제31권2호
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• pp.209-219
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• 1998

갑문을 통하여 유입되는 해수의 양을 산정하고, 1차원 수치모형을 적용하여 운하 속으로 해수의 확산 범위를 파악하였다. 복잡한 양상을 보이는 해수와 담수의 교환과정에서 조위, 갑식의 크기, 운하의 규모, 운영시간만을 고려한 개념적인 모형으로 표현하여 유입되는 해수의 양을 터미널로 배가 들오올 때와 나갈 때, 조위가 운하의 수위보다 높을 때와 낮을 때로 나누어 산정하였다. 본 연구에서 적용한 수치모형은 갑문을 통하여 유입되는 해수는 완전히 혼합된다고 가정하였으며, 또한 갑문을 열 때 갑실 속의 해수와 운하의 담수도 완전히 교환된다고 가정하였다. 서해 쪽 갑문을 통한 손실되는 물의 양을 한강 쪽의 갑문을 통하여 보충하는 경우와 그렇지 않은 경우로 나누어 고려하였다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2009년도 춘계학술발표회
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• pp.89-94
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• 2009

본 연구에서는 부산 북항 재개발의 개발 단계별 해수순환 특성을 살펴보고, 이와 동시에 북항으로 유입되는 4개의 하천의 유량을 갈수기, 평수기, 홍수기로 나누어 각 시기별 하천유량의 유입이 북항의 해수순환에 어떠한 영향을 미치는지를 수치모의하고자 하였다. 결과적으로 부산 북항을 중심으로 한 해수유동 수치모의 시 건설 전과 후에 하천유량이 증가할수록 신선대 방향으로의 Flux가 증가하고 이는 건설 전 후와 상관없이 유동방향이 변하지 않기 때문인 것으로 사료된다. 또한 건설 이전의 홍수시 하천 조건에서의 해수교환율은 60%, 건설 전 후의 해수교환율은 하천유량조건과 관계없이 거의 같은 간으로 해수교환율이 증가하였다.

• Journal of the korean society of oceanography
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• 제37권3호
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• pp.125-133
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• 2002

Water and salt budgets in the Yellow Sea and Bohai are analyzed based on the historical data and CTD data collected recently using box models. The amounts of volume transport and of water exchange across the boundary between the Yellow and East China Seas are estimated to be 2,330-2,840 $\textrm{km}^3$/yr and 109-133 $\textrm{km}^3$/yr, respectively, from the one-layer box model. Corresponding water residence time is 5-6 years. In the Bohai, water residence time is twice as long as that in the Yellow Sea, suggesting that the Yellow Sea and Bohai cannot be considered as a single system in the view of water and salt budgets. The results indicate that water and salt budgets in the Yellow Sea depend almost only on the water exchange between the Yellow and East China Seas. The computation with the coupled two-layer model shows that water residence time is slightly decreased to 4-5 years for the Yellow Sea. In order to reduce uncertainties for the budgeting results the amount of the discharge from the Changjiang that enters into the Yellow Sea, the vertical advection and vertical mixing fluxes across the layer interface have to be quantified. The decreasing trend of the annual Yellow River outflow is likely to result that water residence time is much longer than the current state, especially for the Bohai. The completion of the Three Gorges dam on the Changjiang may be change the water and salt budgets in the Yellow Sea. It is expected that cutting back the discharge from the Changjiang by 10% through the dam would increase water residence time by about 10%.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.124.2-124.2
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• 2010

Generally, a coolant of the nuclear power plant is manufactured by electrolyzing the sea water near the plant for making the sodium hypochlorite(NaOCl), which is used for sterilizing the bacteria and the shellfishes sticking to the drains or the pumps at the outlet of the cooling system due to $8-10^{\circ}C$ warmer temperature than the inlet sea water. During manufacturing the sodium hypochlorite, the hydrogen with the high purity is also produced at the anode side of the electrolyzer. This paper describes a novel power plant system combined with the polymer electrolyte membrane(PEM) fuel cell, the wasted hydrogen from the sea water electrolyzer and the wasted heat of the nuclear power plant. The present status over the exhausted hydrogen at twenty nuclear power plants in Korea was investigated in this study, from which an available power generation is estimated. Furthermore, the economic feasibility of the PEM fuel cell power plant is also evaluated by a current regulations over the power production and exchange using a renewable energy shown in Korea Power Exchange(KRX).