流体力学B

[S04B-04] Numerical Experiments on Bank Erosion of a Steep River with Alternate Bars and Vegetation

*Hirokazu Ikeda¹, Kosuke Iimura¹, Gou Matsuda² (1. Ustunomiya University, 2. Tochigi Prefectural Government)

Keywords:alternate bars, bank erosion, steep river, vegetation, supercritical flow

Numerical experiments were performed on bank erosion of a steep river with alternate bars. It is shown that supercritical flow region appears around upstream part along the front edge of a sand bar, not along the side bank. Meanwhile, maximum bank erosion occurs at water colliding fronts where the flow was subcritical. Effects of vegetation were also examined, which suggest that vegetation pattern is important for bank erosion rather than vegetation volume.