현재 대부분의 하천관리는 일차원 분석이 주로 행해지고 있다. 하지만 유량이나 유속이 커지는 홍수시에는 하상 및 만곡부에 큰 변화가 발생하기 때문에 일차원 분석으로는 한계점이 따르며 결과적으로 오차를 야기시킨다. 본 연구에서는 2차원 유한요소모형인 RMA-2 모형을 한강의 주요 만곡부인 이촌-반포 구간에 적용시켜 편수위 값을 구하고, 이를 기존에 나와있는 편수위 산정공식의 결과값과 비교를 했다. 그 결과, 유량이 클수록 RMA-2 모형과 편수위 산정공식의 결과값의 차이가 커지는 것을 볼 수 있었다.

The purpose of this study is to analyze the sensitivity of the RMA2 model parameters reflecting the flow characteristics of stream junction and thus understand the hydraulic characteristics of the channel confluence flow. This study dealt with the input parameters of the RMA-2 model, a two-dimensional numerical analysis model widely used for researches both at home and abroad. The parameters of the RMA-2 model are roughness coefficient, turbulent diffusion coefficient, Coriolis forces latitude, Density, and mesh size. This study those parameters estimated from actual heavy rainfall, and varied the parameter size by (-)30%～+30% to review the characteristics of the flow characteristics of the channel section. Weobserved that when the ratio of the channel width was relatively small, the smaller the approaching angle was, the farther from the junctions became the generating place of the maximum flow velocity, however, when the ratio of the channel width was relatively large, the larger the approaching angle was, the farther the generating place of the maximum flow velocity from the junctions became. In particular, the distance between junctions and the place where the maximum flow velocity generated showed an absolute correlationover 90% of the relative channel width, but an inverse relationwas found when the distance to the place where the flow velocity generated was shortened as relative the channel width between the main channel and tributary increased.