Author(s): Joo-Young Kim; Jong-Kyu Lee; Jai-Hong Lee; Kwang Seok Yoon
Keywords: Han River; Curved channel; Superelevation; RMA-2; FLDWAV
Abstract: Two dimensional numerical models are applied to two bend reaches of the Lower Han River in Korea, which flows through the Metropolitan, Seoul. The flow characteristics in the meandering river are complicated due to the effects of the centrifugal force. The centrifugal force makes the outside water surface level increase and the outside velocity decrease. The curved channel flow characteristics are useful to design flood control countermeasures, the analysis of sedimentation and the site selection of intake structures. Especially, the superelevation between inside and outside of the bend should be considered to determine the height of embankment. In this study, the water surface elevations in both bank sides of the bend were measured in two reaches during floods in 2007 and 2008. And then the 2-dimensional simulation using RMA-2 model was carried out to compare with the observations. The upstream and downstream boundary conditions on bend reaches were determined by FLDWAV which is 1-dimensional unsteady model. In this paper, the observed data are compared with simulation results and the flow characteristics of the bend are discussed.