• Journal of Korean Society of Coastal and Ocean Engineers
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• 제8권1호
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• pp.18-27
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• 1996

Efforts are concentrated onto effective simulation of surface discharged heat water in two-dimensional depth-averaged finite element model using Gaussian puff algorithm incorporating near-field characteristics as patches computed from CORMIX3 with ambient flow variations. Concise analyses of horizontal and vertical temperature distributions are made for real coastal power plant discharges through four field observations and the results from this proposed method are in good agreements with observations in far-field as well as near-field. Thus, this method can simulate the heat dispersion effectively for the whole region since the complex jet momentum characteristics and ambient flows are easily represented in 10 meters of finite element discretization around a discharging point.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제7권4호
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• pp.340-345
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• 1995

Dispersion characteristics of surface discharge heat water in shallow region are investigated for coastal power plant with nearly constant depth of 20 meters by observing the seasonal depthwide temperature in several stations, which give or precise horizontal distribution and vertical structure of heat water. Surface discharged heat water in shallow coast in the Yellow Sea relies mainly on ambient tidal flow. so it behaves as free jet when the ambient now is strong and shows plumelike behavior during stagnant tide. According to observation the neat field region is estimated as 200-300 meters and shows distinct vertical profile and exponentially decreasing pattern from discharge point for this region. But there are no remarkable vertical distortion of temperature beyond 800 meters even though it is discharged from surface. Characteristic length scale model, CORMIX3, is applied and compared with the field date Overall tendency of CORMIX3 results resemble well with field data especially in near field and intermediate region.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제11권2호
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• pp.116-126
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• 1999

In this paper, we have studied the seasonal vanatIons of near-field dilutions of wastewater discharged from the submerged mutiport-diffuser in Masan Bay. Seasonal changes of temperature and salinity, and tidal currents were measured at 16 stations in Masan Bay. Based on the observed ambient field data, the seasonal changes of near-field dilutions due to ambient current and density fields were calculated by CORMIX model. Because of the shallow ambient water depth of 15 m, the density profiles are isopycnal in autumn and winter seasons, in which the dilution factors were the highest, 168 with the strong spring-tidal current and 110-120 with the weak neap-tidal current. As the season changes from spring to summer, the dilution factors are considerably reduced by the factor of 2 as the thermocline is getting deepened up to Sm in depth in summer. In the case of a weak ambient current, the dilution factor in summer was reduced to 1/4 of the dilution in winter. However, with strong ambient current the difference between summer and winter dilutions becomes relatively small by 30%. The results indicate that the seasonal variation of near-field dilution is very large up to 4 times with a weak neap-tidal current, but its variations become small under a strong ambient current of spring tide in MasanBay.

• Journal of Navigation and Port Research
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• 제43권2호
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• pp.79-85
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• 2019

Climate change is a very vital issue that can be no longer avoided. Korea has been a top-level country Iin dealing with carbon dioxide emissions since 1960. Many studies have been conducted to suppress or eliminate carbon dioxide emissions, which account for a large portion of greenhouse gases. Carbon Capture and Storage (CCS), the most practical method of them, plays a significant role. However, these methods have the disadvantage of the limits of geographical distribution and high possibility of re-emission into the atmosphere. Recently, ocean storage has been studied using Accelerated Weathering of Limestone (AWL), a technique for storing carbon dioxide in the ocean as an alternative to CCS, an underground storage. AWL is a method of converting carbon dioxide into concentrated water in the form of bicarbonate ion and discharging it to the ocean to dilute and store it. It does not cause re-emission to the atmosphere, and the discharged concentrated water increases the alkalinity of the ocean to prevent marine acidification. The objective of this study was to understand the behavior of DIC (Dissolved Inorganic Carbon) including carbon dioxide during the ocean discharge of bicarbonate ion concentrated water in AWL method. This study area was set near Ulleung-do where sufficient water depth and operational efficiency were secured. CORMIX model was used to calculate the material diffusion by submerged discharge using ship.

• Journal of Korean Society of Coastal and Ocean Engineers
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• 제10권2호
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• pp.73-82
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• 1998

In order to simulate surface discharged heat dispersion in costal area, a 2-dimensional Eulerian-Lagrangian model for far field and semi-active particle tracking random walk model in near field has been combined. The mass of discharged heat water in near field has treated as particles with buoyancy and this is eventually converted to horizontal additive dispersion in random walk equations. This model is applied to both a simplified coastal geometry and a real site. In simple application it can simulate plume-like characteristics around discharging point than a near field-model, CORMIX/3. Actual application in the Chonsu Bay shows farther spreading of heat water in near field comparing the observed data, and this shows that the developed model might be applied with satisfaction.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 한국항해항만학회 2000년도 추계학술대회논문집
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• pp.85.2-93
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• 2000

A demand of marine outfall system have been much increased for the effective disposal of the wastewater due to population and industrial development at the coastal areas. The outfall system discharges primary or secondary treated effluent into coastline or at the deep water, or between these two. The discharge is carried out by constructing a pipeline on the sea bed with a diffuser or with a tunnel, risers and appropriate. The effluent, which has a density similar to that of fresh water, rises to the sea surface forming plume or jet, together with entraining the surrounding salt water and becomes very dilute. Thus there have been growing interests about plume behaviour around the outfall system. Plume or jet discharged from single-port or multi-port diffuser might cause certain impacts on coastal environment. Near field mixing characteristics of discharged water field using CORMIX model with has been studied for effective outfall design various conditions on ambient current, depth, flow rate, effluent concentration, diffuser specification, port specification etc.. This kind of analysis is necessary to deal with water quality problems caused by the ocean discharge. The analyzed vesult was applied to the Pusan Jungang dffluent outfall system plan.

• Journal of Korean Port Research
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• 제14권2호
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• pp.241-249
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• 2000

The amount of municipal water has been increased rapidly up to now and it is necessary to treat and dispose the wastewater effectively. The recent trend of the effluent disposal system, after treatment, show a nearshore discharge which has an outfall with length somewhere between the shoreline discharge and an extended deepwater outfall. There is no universal solution to municipal water treatment and disposal and each case must be examined on its merits and on economic, technical and environmental bases. In this study we focused mostly on the scientific and engineering aspects of ocean disposal through the outfall. For this purpose, we made an investigation to the near-field characteristics of discharged water and made some comparison with the existing experimental results. We also applied it to the Pusan Jungang Effluent Outfall System, which is planned to build in the Gamchun harbour and will be completed in 2011. The model output showed the trajectoral variation of dilution and mixing behavior for three cases of outfall system. Dilution differences have been simulated and found the highest dilution condition under the different displacement of outfall system. On the basis of these outputs it will be proposed the optimum outfall system type and location.