• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.11
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• pp.1060-1071
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• 2005

Passive gas dispersions over a 1/1000 scale terrain model at Eiffel type wind tunnel were reproduced by numerical simulation. Large eddy simulation was used to treat the sub-grid scale turbulences. The terrain features were represented by millions of point forces densely distributed over the solid surface using the virtual boundary method. The model simulations agreed very well with the experiments in a consistent fashion for all wind directions. The measured profiles of the wind speeds as well as the tracer gas concentrations were nicely simulated by the CFD model at most locations scattered over the model terrain. With scale factor adjusted and the thermal stratification effects incorporated, the CFD model was expected to provide reliable information on pollutant dispersions over the real complex terrains.

• Journal of computational fluids engineering
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• v.6 no.4
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• pp.1-7
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• 2001

Wind flow perturbations, recirculations and turbulence generated by buildings often dominate air pollutant distributions around buildings. This paper describes dispersion of contaminants in the vicinity of a building by solving the concentration equation based on previously simulated wind flow field. Turbulence closure is achieved by using the standard k-ε two-equation model. The paper shows application of the CIP method for solving a species concentration equation of contaminant gas around a rectangular building for two different sources under conditions of neutral atmospheric stratification. Results have been compared to the experimental data and the previous numerical results by hybrid scheme. The computational results of concentration profiles by the CIP method agree well with experimental data.

• Journal of Ocean Engineering and Technology
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• v.24 no.4
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• pp.78-85
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• 2010

This study investigates reducing characteristics for the spreading of dredged soil and the diffusion of contaminant by silt protector curtain through three dimensional numerical experiment. The numerical medel is modified by combining the sediment transport characteristics for cohesive sediment into the previously developed model. Several numerical experiments have been given in order to investigate the reducing effect of silt protector using two dimensional numerical channel model under various parameters such as upstream flow velocity, depth of silt curtain and the position of dumped materials. Through the evaluation of several simulation results, we knew that the careful design has to be given in the determination of depth and position of silt protector.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.723-728
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• 2001

Wind flow perturbations, recirculations and turbulence generated by buildings often dominate air pollutant distributions around buildings. This paper describes dispersion of contaminants in the vicinity of a building by solving the concentration equation based on previously simulated wind flow field. Turbulence closure is achieved by using the standard k-e two-equation model. The paper shows application of the CIP method for solving a species concentration equation of contaminant gas around a rectangular building for two different sources under conditions of neutral atmospheric stratification. Results have been compared to the experimental data and the previous numerical results by hybrid scheme. The computational results of concentration profiles by the CIP method agree well with experimental data.

• Journal of the Korean Geotechnical Society
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• v.17 no.4
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• pp.49-55
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• 2001

본 논문에서는 서해안 폐기물 매립지 하부의 점성토와 고화차수재를 재료로 수행된 확산시험 결과와 현장 조건을 적용하여 오염물이동성에 대한 수치해석을 수행하였다. 무기화합물이 하부 차수재와 원지반퇴적층으로 이동되는 일차원 이동 특성을 대상으로 하였으며 일차원 용질이동해석 프로그램 CDFD(convection-dispersion finite difference)를 현장의 비균질한 지층에 이용할 수 있도록 수정하여 적용하였다. 그 결과 원지반점성토를 통한 용질이동 메카니즘에 확산이 기여하는 정도가 50%로 매우 큰 영향을 갖고 있음을 보여주며 원지반 투수계수가 클수록 인공차수층의 필요성이 증대됨을 알 수 있었다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.74-78
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• 2012

본 연구는 하천에서 식생에 의한 흐름구조 변화가 오염물질 이동에 미치는 영향을 알아보기 위해 흐름방향 확산계수를 산정하였다. 정수식생 조건에서 횡방향 수심적분된 와점성계수는 비식생 조건에서의 와점성계수와 다르게 적용되어야 하며 이를 위해 유량 횡분배법을 Jordanova and James (2003) 실험에 적용하였다. 제시된 실험조건을 잘 재현하는 와점성계수의 값을 역산하였으며, 이에 관한 산술평균 값을 향후 수리모형의 적용을 위해 정수식생 조건에서의 무차원 와점성계수로 제안하였다. 결정된 무차원 와점성계수를 이용하여 부분식생 개수로 흐름에서 흐름방향 확산계수를 산정하여 오염물질의 이동에 대한 특성을 분석하였다.

• Journal of the Korean Society of Groundwater Environment
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• v.2 no.1
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• pp.1-8
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• 1995

Wastes produce groundwater contamination, offensive odor, and hazardous gases. This study investigates the contamination of groundwater at the Seokdae waste landfill area and seeks the desirable ways to minimize the groundwater contamination. Groundwater levels, water chemistry and aquifer characteristics of wells were examined around the Seokdae waste landfill. The water chemistry of the Dong stream, the groundwater distribution and flow were also studied. The results of this research show that the estimated quantity of the percolation from the landfill base to the ground is 520 ㎥/day and the extent of groundwater contamination is about 1-1.5 km from the center of the waste landfill. The groundwater contains heavy metals and other toxic elements. The conservation and management of the groundwater of the waste landfill need several monitoring wells to check the quantity and quality of groundwater, pumping wells to extract the contaminated groundwater, and slurry walls to protect the movement of contaminated groundwater.

• Journal of the Society of Disaster Information
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• v.14 no.2
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• pp.141-153
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• 2018

Purpose : The subject site selected in this study was a place that was prepared through the reclamation of foreshore completed in 1973. Since then, the site has been occupied by the industry of ship repair for over 30 years. Method : The results of a precise soil examination conducted in 2013 showed that the site was seriously contaminated with TPH over an area of $10,000m^2$ and GL(-)3.0m in depth, with an expanding coverage of contamination. Results : The soil contamination by refined petroleum products often results in adverse effects to human health and ecological systems, thus the contamination should be purified as soon as possible. Conclusion : Hydrogeological investigation can be employed to assess the groundwater movement and propagation of contamination to determine the potential agents or contaminants in the soil contaminated with high concentration TPH.

• Journal of the Korean Geotechnical Society
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• v.27 no.1
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• pp.35-40
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• 2011

Dredging and disposal is a conventional method to remove contaminated sediments. However, there are some problems in dredging and disposal, such as disturbance of contaminated sediments, disposal site determination, and high construction cost. Recently, in-situ capping which overcomes the problems of dredging and disposal is widely applied to isolate local contaminated sites. Numerical studies, which have been conducted to simulate contaminant transport during in-situ capping, have been concerned mainly with diffusive transport. However, contaminated sediments experience large strain consolidation induced by self-weight because of initially high moisture content of sediments, and contaminant transport results from advection and diffusion. Previous studies focus on contaminant transport during consolidation, but have neglected consolidation effect on long-term contaminant transport in sediments. This study presents numerical simulation results of consolidation effect on long-term contaminant transport in sediments.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.355-359
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• 2006

토양에 누적된 오염물질은 지하수 유동과 연계하여 점차 주변지역으로 확산된다. 본 조사는 오염의 개연성이 높은 산업단지를 선정하고 그 중에서도 유해화학물질의 사용이 많은 지역을 대상으로 토양과 지하수의 오염도조사를 수행하였다. 토양오염도 조사는 160개 지점에서 토양시료를 채취하여 오염물질을 분석하였으며 분석결과 TPH물질은 최고 23,151mg/kg, BTEX는 최고 1,657mg/kg로 검출되었다. 오염특성은 유류(TPH, BTEX) 물질 이외에도 TCE, PCE◎물질과같은 염소계 유기용제에 의한 오염도 확인할 수 있었으나 중금속 물질에 의한 오염은 우수 방류구와 같은 일부 지역에서 검출되었다. 지하수 수질의 경우 페놀, 비소, 납, BTEX, TCE, PCE 물질들이 복합적으로 오염되어있는 것으로 나타났다.