• 수도
• /
• s.69
• /
• pp.47-58
• /
• 1994

• Proceedings of the Korea Water Resources Association Conference
• /
• 2000.05a
• /
• pp.691-696
• /
• 2000

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.11 no.2
• /
• pp.116-126
• /
• 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.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2022.05a
• /
• pp.351-351
• /
• 2022

현재 우리나라는 기후변화가 심화되고 강우의 불확실성이 높아지면서 자연 재해와 홍수 피해가 증가하고 있고 이에 따른 댐이나 보 운영의 고도화가 요구되고 있다. 특히 댐의 경우 다양한 원인에 의해 상류와 하류에서 홍수 피해가 빈번하게 발생하기도 하며, 방류 조절에 따라 담수 유입으로 인한 해수의 염도 변화나 수질 오염 등의 결과를 야기시킨다. 따라서 효율적인 댐 운영을 위해서는 방류량에 대한 지속적인 검증 측정이 필요하며, 유역 내 상하류 유출 특성 변화에 대한 모니터링이 요구된다. 따라서 본 연구에서는 탐진강 유역에 위치한 장흥군(별천교)관측소와 장흥군(예양교)관측소를 대상으로 가동보 운영과 식생영향, 취수영향, 공사에 따른 수위-유량관계 변화를 분석하였다. 탐진강 최상류에 위치한 장흥군(별천교)관측소의 경우 2013년 이후 유량조사가 이루어지지 않아 2021년 하류 가동보 수문 운영 조건과 수중식생 영향, 취입보 운영 조건에 따른 변화를 모니터링하고 유량측정을 실시하여 수위-유량관계의 변동성을 분석하였다. 또한 탐진강 하류에 위치한 장흥군(예양교)관측소는 기존 설치되어 있던 상하류 가동보에 대해 철거공사가 금년 진행되었으며, 이에 따른 지속적인 모니터링과 유량측정을 통해 흐름 특성 변화를 분석하였다. 추가로 저평수기와 홍수기에 장흥댐 수문 방류량에 대한 검증 측정을 수행하여 고시된 방류량과 실측된 방류량을 각각 적용하여 탐진강 유역 유출 특성 변화에 대해 분석하였다. 결과적으로 본 연구에서는 탐진강 유역 하천 내의 보 운영과 식생, 취수, 공사영향에 따른 모니터링과 유량측정을 통해 신뢰도 높은 수위-유량관계곡선식을 개발하였고, 이를 통해 생산된 유량자료는 정확도가 매우 높은 것으로 분석되었다. 또한 장흥댐 수문 방류량에 대해 실제 측정된 방류량을 유출 분석에 적용한 결과 향상된 결과를 보였으며 정상적인 상하류 관계를 나타냈다.

• Journal of Korea Water Resources Association
• /
• v.33 no.S1
• /
• pp.691-696
• /
• 2000

• Journal of Korea Water Resources Association
• /
• v.54 no.2
• /
• pp.135-144
• /
• 2021

This paper attempted to find implications for water resource management and water quality improvement by analyzing the causal relationship among discharge, water temperature and pollution index, which were expected to have a great effect on water quality with the rise of water temperature and precipitation change as the warming effect in recent years. For this purpose, the unit root test, cointegration test, and Granger causal test were carried out for 10 multi-purpose dams in Korean major water systems using time series data on discharge, water temperature, BOD, COD and DO. It was analyzed that the fluctuation of water temperature affected the pollution index more than the fluctuation of discharge volume. Also, Hapcheon dam and Chungju dam were the best water quality management dams based on the high causal relationship between water quality and discharge. The second rank was Daecheong dam. The third-ranking group were Yongdam and Andong dam, whose causal relationships between water quality and discharge were low. The last group were the remaining five dams.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.10 no.3
• /
• pp.132-140
• /
• 1998

The quantitative analysis on the pollutants loads (PL) has hardly been carried out and calibration-verification process of the water quality modeling has been conducted under the restricted condition because the observed PL data are not sufficient. In this study, the PLs were measured at the 22 streams and the effluents site in the Masan-Changwon watersheds. The release rates from sediment were also measured at the three points in the Bay. The PLs from the Masan and Changwon cities and from multi-port diffuser(effluents discharge) amount to 80∼90% and 20∼25% of the PL in Chinhae-Masan Bay, respectively. As the amounts of the sediment released pollutants are the same order of the PLs form the watersheds, the pollutants released from the sediment is one of the main factors that might cause the seasonal variation of the water quality, which is degraded in summer and relatively good in winter.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
• /
• 2000.09a
• /
• pp.126-132
• /
• 2000

하수처리장의 수중확산관에서 방류되는 부력제트는 초기혼합, 중력확장, 이송-확산 등의 과정이 시간적, 공간적으로 규모가 상이한 범위에서 일어나며, 하수방류 해역의 주변수 흐름은 지형특성과 조석의 영향을 받아 3차원적 비정상류 특성을 나타낸다. 이러한 부력제트의 거동을 모의하기 위해서는 일반적으로 근역과 원역을 분할하여 예측하는 방법을 사용하는데, 초기혼합 과정과 중력환장 과정을 예측하기 위해서는 정상상태는 가정한 특성길이 모형이나 제트적분 모형을 사용하고, 원역으로의 이송-확산 과정을 모의하기 위해서는 농도 모형이나 임자추적 모형등을 사용한다. (중략)

• Journal of Korean Society of Water and Wastewater
• /
• v.22 no.3
• /
• pp.389-396
• /
• 2008

The hybrid model can be used to predict the initial near field mixing and the far field transport of the buoyant jets, which are discharged from the submerged wastewater ocean outfall. In the near field, the jet integral model can be used for single port diffusers while the ${\sigma}$ transformed particle tracking model was used in the far field. In this study, the experimental study was performed to verify the developed hybrid model in the previous research. The developed hybrid model properly predict the surface and vertical concentration distribution of the single buoyant jets with various effluent and ambient conditions. The hybrid model can also simulate the surface concentration distribution of the rosette diffuser except for the parallel diffuser with the higher densimetric Froude number due to the assumption that dynamic effects of the effluent plumes are negligible in the far field. The application of the hybrid model to rosette diffusers can predict the concentration near the diffuser more accurately when the line-plume approximation is used.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2019.05a
• /
• pp.43-47
• /
• 2019

In this study, capability of an air slot in a siphon spillway for controlling outflow discharge is investigated through hydraulic experiments. Arc and rectangular shapes of air slot are considered and the open area of air slot can be varied. Complex air-regulated flow occurs inside the the siphon spillway when the air slot is installed on it. The same discharge is measured at the same water level inside the reservoir when the water level rises or falls. Nondimensional discharge through the siphon spillway increases slowly as nondimensional open area of the air slot increases. The hydraulic experiments show that the control of outflow discharge of siphon spillway is possible by controlling the open area of the air slot.