1. 小角度斜向入流条件下复式断面 明渠流速重分布线性理论.
- Author
-
许 栋, 黄雄合, 及春宁, and 白玉川
- Abstract
The directions of flow in natural compound river channels are frequently influenced by the discharge and floodplain⁃main channel configuration, which may lead to a small intersec⁃ tion angle between the flow and the channel. Hence, lots of existent theories for floodplain flows under the assumption of uniform straight channels may be inapplicable. To investigate the influence of oblique inflow, shallow water equations were used to describe flow motion in com⁃ pound open channels. The perturbation method was used with a small parameter of the oblique angle to derive the analytical solution for flow in compound open channels under inflow with small oblique angles. The solutions were verified with numerical simulation results and the flow velocity distributions agreed well. Theoretical results show that the obliquity of inlet flow lead to asymmetrical velocity distribution across the cross section of a compound channel, which is featured by an increase of velocity in the upstream side and a decrease in the downstream side of the main channel. Under an oblique angle of 13° and a floodplain⁃main channel water depth ratio of 3∶8, the flow velocity deviation may reach 21.8% of the value in the straight flow case. Such a deviation increases with the decreasing of the floodplain⁃main channel water depth ratio. The proposed modification to flow velocity distribution may improve the accuracy of hydrody⁃ namic conditions for further research on sediment transport and evolutions of compound chan⁃ nel rivers. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF