한국수자원학회논문집 (Journal of Korea Water Resources Association)

한국수자원학회 (Korea Water Resources Association)
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낙동강 - 남강 합류부 대하천 규모 수리학적 혼합특성 연구

Hydraulic mixing characteristics at a large-scale confluence of Nakdong and Nam River

  • 최수인 (단국대학교 토목환경공학과) ;
  • 김동수 (단국대학교 토목환경공학과) ;
  • 김영도 (명지대학교 토목환경공학과) ;
  • 류시완 (창원대학교 토목공학과)
  • Choi, Suin (Department of Civil & Environmental Engineering, Dankook University) ;
  • Kim, Dongsu (Department of Civil & Environmental Engineering, Dankook University) ;
  • Kim, Youngdo (Department of Civil & Environmental Engineering, Myongji University) ;
  • Lyu, Siwan (Department of Civil Engineering, Changwon University)
  • 투고 : 2023.09.20
  • 심사 : 2023.10.19
  • 발행 : 2023.12.31
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초록

하천의 합류부는 본류와 지류가 만나 복잡한 혼합거동을 보이는 지역으로 두 하천이 혼합되지 않은 채 하류로 이동하는 현상이 발생하기도 한다. 하천이 혼합되지 않고 유지되면 하천의 수질 관리에 어려움을 주거나 남강 합류부 인근 취수장(칠서)에서 취수되는 수체의 특성이 모호할 수 있다. 본 연구에서는 드론 영상과 수질 인자 전기전도도, 수리 인자 2차류를 통해 낙동강과 남강 합류부에서의 혼합거동을 면밀하게 분석하였다. 2차류의 분석은 Rozovskii 방법을 기반으로 2중 나선형 구조의 확인이 용이하게 하였다. 연구 결과 만곡의 영향으로 인해 혼합이 방해 받고 있음을 2차류 분포와 전기전도도 분포의 비교 분석을 통해 확인하였으며, 낙동강-남강 합류부 하류의 칠서 정수장은 해당 시기 혼합되지 않은 남강 수체를 취수하고 있음을 확인하였다.

The confluence of rivers, where rivers meet, is a place known for complex water mixing dynamics. Sometimes, these rivers flow downstream without mixing. While this non-mixing can pose challenges for water quality management, it also offers the potential for improved water extraction in nearby water intakes (Chilseo). In this study, we analyzed the mixing dynamics at the confluence of the Nakdong River and the Nam River using drone imagery, water quality indicators like Electrical Conductivity, and hydraulic factor Secondary Flow. We found that meandering effects hindered mixing, as shown by the comparison of Secondary Flow and Electrical Conductivity distributions. Additionally, the Chilseo Water Purification Plant downstream of the Nakdong River-Nam River confluence extracted unmixed Nam River water during certain periods.

키워드

과제정보

본 연구는 환경부 미세플라스틱 측정 및 위해성 평가 기술개발사업(202100311003) 및 낙동강수계관리위원회 연구용역과제(수질변화 예측을 위한 남강과 낙동강 합류부의 수체혼합 유동분석)의 연구비 지원에 의하여 연구되었으며 이에 감사드립니다.

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